Infectious diseases are caused by germs — viruses, bacteria or other pathogenic microbes. Germs that can infect the respiratory system — lungs, throat, airways — can often be spread through mucus and saliva (also known as "respiratory secretions") expelled when a person coughs, sneezes, talks or laughs. Some of these germs are spread through droplets small enough to remain suspended in the air and travel over long distances. Another person can become ill when they inhale these microbes or when the microbes contact their mucous membranes. More often, germs are spread through larger droplets that don't remain suspended in the air and travel only short distances (less than three feet). Another person can become infected when they touch secretions remaining on a surface or on someone's hands, or through close contact with an infected person, such as sharing eating utensils or drinking from the same glass.

Transmission of infectious respiratory diseases from one person to another can be greatly reduced by taking the following precautions:

• Wash your hands frequently with soap and water — it is one of the most effective ways to reduce spread of illness. Alcohol-based hand sanitizers are also effective if soap and water are not available.
• Minimize close contact with sick people.
• Get immunized. A number of infectious respiratory diseases, such as flu, measles, mumps, rubella and whooping cough, are vaccine-preventable.
• Stay home when you are ill.
• When you are ill, allow a few feet of distance from others.
• Cover coughs and sneezes with your elbow or tissue but not your hand.
• When you are ill, you may also wear a surgical-type mask when around others.

In the case of water-droplet aerosolized pathogens, such as those that cause Legionnaires' disease, environmental controls (such as disinfection and in-depth cleaning) and engineering alternatives (such as special air-handling and ventilation systems) might be needed to help reduce transmission.

Diseases that can infect the respiratory system include:

• Chickenpox (varicella)
• Coronavirus infections (including SARS-CoV and MERS-CoV)
• Diphtheria
• Group A streptococcus
• Haemophilus influenzae type b
• Influenza (flu)
• Legionnaires' disease
• Measles (rubeola)
• Middle East Respiratory Syndrome (MERS)
• Mumps
• Pneumonia
• Pneumococcal meningitis
• Rubella (German measles)
• Severe Acute Respiratory Syndrome (SARS)
• Tuberculosis
• Whooping cough (pertussis)

A number of less common infectious diseases that may result in respiratory illness are animal-borne (zoonotic), including:

• Anthrax
• Brucellosis
• Hantavirus
• Psittacosis
• Plague
• Q Fever
• Tularemia

What to know

• In addition to CDC’s Respiratory Virus Guidance, there are several specific considerations for people who are at higher risk for severe illness.

Overview

Illnesses caused by respiratory viruses like COVID-19, flu, and RSV can make anyone sick. However, there are a range of risk factors that can increase a person’s chances of getting very sick (severe illness). Generally, people at higher risk of severe illness from respiratory viruses are older adults, young children, people with compromised immune systems, people with disabilities, and pregnant people.

Making a plan

If you or someone around you has one or more risk factors for severe illness, using the prevention strategies described in CDC's Respiratory Virus Guidance is especially important. In addition, there are several specific considerations for people with certain risk factors for severe illness:

• Older adults
• Young children
• People with weakened immune systems
• People with disabilities
• Pregnant people

What to know

• In addition to CDC’s Respiratory Virus Guidance, there are several specific considerations for people who are at higher risk for severe illness, including older adults.

Overview

As people get older, their immune systems do not work as well. Older adults are also more likely to have underlying health conditions. Most deaths from respiratory viruses occur in people older than 65, with risk increasing sharply with advancing age.

Why prevention is important

Studies have shown that:

• Compared to people ages 18-39 years, people ages over 75 are about 9 times as likely to die from COVID-19. Learn more.
• Each year, it is estimated that 60,000-160,000 older adults in the United States are hospitalized due to RSV infection and 6,000-10,000 die. Learn more.
• In recent years, it's estimated that between 70 percent and 85 percent of seasonal flu-related deaths in the United States have occurred among people 65 years and older, and between about 50 percent and 70 percent of seasonal flu-related hospitalizations have occurred among people in this age group. Learn more.
• Over 95% of adults hospitalized in 2023-2024 due to COVID-19 had no record of receiving the latest vaccine.

Making a Plan

Reducing risk‎

If you are, or if you spend time with, an older adult, using the prevention strategies described in CDC's Respiratory Virus Guidance is especially important. In addition, there are several specific considerations for older adults listed below.

Immunizations

• In addition to getting a current COVID-19 vaccine, there are some unique respiratory virus immunization recommendations for older adults:
  • All adults ages 65 years and older are recommended to receive an additional updated 2023-2024 COVID-19 vaccines dose.
  • All adults should have a current flu vaccine, but adults aged 65 years or older are recommended to receive a high dose or adjuvanted flu vaccine (for example, Fluzone High-Dose Quadrivalent inactivated flu vaccine, Flublok Quadrivalent recombinant flu vaccine, or Fluad Quadrivalent adjuvanted inactivated flu vaccine).
  • Adults ages 60 years and older should talk to their healthcare provider about whether an RSV vaccine is right for them.
• The Eldercare Locator, a national resource funded by the Administration for Community Living, can help older adults find local vaccination clinics, connect with accessible transportation, and provide other assistance in accessing vaccinations.
• In addition to getting a current COVID-19 vaccine, there are some unique respiratory virus immunization recommendations for older adults:

Masks

Note that better fitting masks (for example, N95 or KN95 respirators) are more effective at protecting you from inhaling germs than other types of masks are (for example, cloth masks or surgical/disposable masks).

Treatment

• COVID-19 antivirals are recommended for all older adults (over age 50) and certain people at higher risk for complications from COVID-19.
• Flu antivirals are recommended for certain people at high risk for complications from flu, including adults ages 65 years and older.
• To learn more about if treatment is right for you, speak with a healthcare provider.

Tests

The Administration for Community Living and the Administration for Strategic Preparedness and Response are partnering to distribute tests to the aging and disability networks. You may be able to get COVID-19 tests for free through your Area Agency on Aging.

What to know

• In addition to CDC’s Respiratory Virus Guidance, there are several specific considerations for people who are at higher risk for severe illness, including young children.

Overview

Young children, particularly infants, have immune systems that are still developing. In addition, their lungs and airways are smaller, making viruses that affect airways more of a threat.

Why prevention is important

Studies have shown that:

• Infants under 6 months of age have similar COVID-19–associated hospitalization rates to adults ages 65–74 years old. Learn more.
• Each year in the United States, an estimated 58,000-80,000 children younger than 5 years are hospitalized due to RSV infection, with infants being among those at greatest risk. Learn more.
• Children younger than 5 years old, but especially those younger than 6 months, are at higher risk of developing serious flu-related complications. CDC estimates that from 2010 to 2020, flu-related hospitalizations among children younger than 5 years ranged from between 6,000 to 27,000 per year in the United States. Many more have to go to a doctor, an urgent care center, or the emergency room because of flu. Learn more.

Reducing risk

Immunizations

COVID-19 and flu

• Young children ages 6 months or above are recommended to have a current COVID-19 vaccine and an annual flu vaccine.
• Two doses of the flu vaccine (separated by at least 4 weeks) are recommended for those ages 6 months–8 years who have received fewer than 2 flu vaccine doses before July 1, 2023, or whose flu vaccination history is unknown.
• Though they are not eligible for COVID-19 or flu vaccines, infants under age 6 months can still receive some protection. Getting vaccinated while pregnant or breastfeeding can help protect a baby after birth because antibodies are passed to the baby during pregnancy or through the milk.

RSV

• To prevent severe RSV disease in infants, CDC recommends either RSV vaccination while pregnant or infant immunization with RSV protective antibody. Most infants will not need both.
• RSV vaccination in pregnancy takes place during weeks 32 through 36 of pregnancy and is administered September through January in most parts of the United States. Abrysvo is the only RSV vaccine recommended during pregnancy.
• Immunization for infants and young children with RSV monoclonal antibody consists of:
  • 1 dose of nirsevimab for all infants ages 8 months and younger born during or entering their first RSV season.
  • 1 dose of nirsevimab for infants and children ages 8–19 months who are at increased risk for severe RSV disease and entering their second RSV season.
  • Note: A different monoclonal antibody, palivizumab, is limited to children ages 24 months and younger with certain conditions that place them at high risk for severe RSV disease. It must be given once a month during RSV season.

Hygiene

• Handwashing can become a lifelong healthy habit if you start teaching it at an early age. Teach kids the five easy steps for handwashing—wet, lather, scrub, rinse, and dry—and the key times to wash hands, such as after using the bathroom or before eating..
• Supervise young children when they use hand sanitizer to prevent swallowing alcohol.

Masks

• Masks should not be worn by children younger than 2 years because of suffocation risk.

Treatment

• Paxlovid (nirmatrelvir-ritonavir) antiviral treatment for COVID-19 is not authorized for use in children younger than 12 years of age. Other treatment may be available, speak with a healthcare provider.
• There are flu antiviral drugs recommended by CDC for use in children. Oseltamivir (available as a generic version or under the trade name Tamiflu®) is approved for treatment of flu in children 14 days old and older.
  • Note: Although not part of the FDA-approved indications, use of oral oseltamivir for treatment of flu in infants less than 14 days old, and for chemoprophylaxis in infants 3 months to 1 year, is recommended by the CDC and the American Academy of Pediatrics. If a child is younger than 3 months old, use of oseltamivir for chemoprophylaxis is not recommended unless the situation is judged critical due to limited data in this age group.
• To learn more about if treatment is right for your child, speak with a healthcare provider.

When Sick

• Parents and caregivers may need to be around young children at home when they are sick because they require supervision. When caring for a young child who has a respiratory virus, make use of other prevention strategies like taking steps for cleaner air, being diligent with hygiene practices, and choosing to use a mask if over age 2.
• Know that the emergency warning signs of respiratory virus complications can be different in children. Seek immediate medical care for any of the following:
  • Fast breathing or trouble breathing
  • Bluish lips or face
  • Ribs that pull in with each breath
  • Chest pain
  • Severe muscle pain (for example, child refuses to walk)
  • Dehydration (no urine for 8 hours, dry mouth, no tears when crying)
  • Lack of alertness or interacting when awake
  • Seizures
  • Fever above 104 degrees Fahrenheit that is not controlled by fever-reducing medicine
  • In children younger than 12 weeks, any fever
  • Fever or cough that improves but then returns or worsens

What to know

• In addition to CDC’s Respiratory Virus Guidance, there are several specific considerations for people who are at higher risk for severe illness, including people with weakened immune systems.

Overview

People with weakened immune systems (immunocompromise) have lower defenses against infections, and their bodies may have a harder time building lasting protection from past immunization or infection. People can be immunocompromised either because of a medical condition or because they receive immunosuppressive medications or treatments.

Examples of medical conditions or treatments that may result in moderate to severe immunocompromise include, but are not limited to, cancer treatment, organ transplant with immunosuppressive therapy, and primary immunodeficiency.

Why prevention is important

Studies have shown that:

• Among people who had either a solid organ transplant or a stem cell transplant, about 65 percent of those who got flu were hospitalized. Learn more.
• Risk of death among hospitalized people with COVID-19 was about 1.44 times greater among those who were immunocompromised than those were not. Learn more.

Making a plan

Reducing risk‎

If you have, or someone you spend time with has, a weakened immune system using the prevention strategies described in CDC's Respiratory Virus Guidance is especially important. In addition, there are several specific considerations for people with weakened immune systems.

Immunizations

COVID-19

• Everyone ages 6 months and older who is moderately or severely immunocompromised should receive at least 1 dose of a 2023-2024 updated COVID-19 vaccine. Depending on the number of doses you've previously received, you may need more than 1 dose of updated vaccine:
  • If you have not gotten any COVID019 vaccines (not vaccinated), you should get 2 or 3 doses of updated COVID-19 vaccine, depending on which vaccine you receive.
  • If you got 1 previous Pfizer-BioNTech or Moderna COVID-19 vaccine you should get 1-2 doses of updated COVID-19 vaccine.
  • If you got 2 or more previous COVID-19 vaccines, you should get 1 updated COVID-19 vaccine.
• Recommendations may vary based on your age. See additional information on COVID-19 vaccines for people who are immunocompromised.

Flu

• Immunocompromised persons should receive an age-appropriate flu vaccine.
  • Live attenuated influenza vaccine (the nasal spray flu vaccine) should not be used.
  • Note that timing flu vaccination relative to a specified period before or after interventions that compromise immunity may be appropriate.
  • Additional information on flu vaccines for people who are immunocompromised is available here.

Masks

• Note that better fitting masks (for example, N95 or KN95 respirators) are more effective at protecting you from inhaling germs than other types of masks are (for example, cloth masks or surgical/disposable masks).

Treatment

• If you have COVID-19, antiviral treatments are recommended for people with weakened immune systems. If you have a weakened immune system, have received antiviral treatment, and continue to experience COVID-19 symptoms, your healthcare provider may recommend additional treatment.
• If you have flu, antiviral treatments are recommended for people with weakened immune systems.
• To learn more about if treatment is right for you, speak with a healthcare provider.

When Sick

• It can take longer than average for people with weakened immune systems to recover from respiratory viruses. This includes a possible longer duration during which you can spread a respiratory virus to others. If you are immunocompromised, be aware of this when choosing precautions after you return to normal activities following time at home sick.

What to know

• In addition to CDC’s Respiratory Virus Guidance, there are several special considerations for people with certain risk factors for severe illness, including people with disabilities.

Overview

Some disabilities can raise a person's risk of getting very sick from respiratory viruses. For example, some people with disabilities are more likely to have underlying medical conditions, live in congregate settings, or experience factors and conditions stemming from social determinants of health.

Why prevention is important

Studies have shown that:

• People with certain disabilities have a higher risk of getting respiratory virus-related complications, for example:
  • During the first two COVID-19 pandemic waves, people with intellectual disabilities were equally as likely as other people to become infected but had 3.5 times the risk of death. Learn more.
  • Children with neurologic and neurodevelopmental disorders are estimated to be at 5 to 7 times greater risk of hospitalization from respiratory infections than other children. Learn more.

Making a plan

Reducing risk‎

If you have, or someone you spend time with has, a disability using the prevention strategies described in CDC's Respiratory Virus Guidance is especially important. In addition, there are several specific considerations for people with disabilities.

Immunizations

The Disability Information and Access Line (DIAL) can help people with disabilities find local vaccination clinics, connect with accessible transportation, and provide other assistance in accessing COVID-19 vaccinations (e.g., set up vaccination appointment).

Masks

• Note that better fitting masks (for example, N95 or KN95 respirators) are more effective at protecting you from inhaling germs than other types of masks are (for example, cloth masks or surgical/disposable masks).
• Some people with disabilities may find it difficult to wear a mask. Challenges may be caused by being sensitive to materials on the face, difficulty understanding the value of mask wearing for protection, or having difficulty keeping the mask in place. When considering whether to use a mask, people with disabilities or their caregivers can consider the person's ability to wear a mask correctly (proper mask size and fit), to avoid frequent touching of the mask and face, and to remove the mask without assistance.
• For people who are deaf or hard of hearing, or people who spend time with someone who is, clear masks or masks with clear panels are an option.

Steps for cleaner air

Note that taking additional steps for cleaner air can be particularly helpful if you are not able to wear a mask or distance from others; for example, if you need personal assistance or direct support.

Treatment

• COVID-19 antivirals are recommended for certain people at high risk for complications from COVID-19, including people with many types of disabilities.
• Flu antivirals are recommended for certain people at high risk for complications from flu, including people who live in congregate settings and people with many types of underlying medical conditions.
• To learn more about if treatment is right for you, speak with a healthcare provider.

Tests

• The Administration for Community Living and the Administration for Strategic Preparedness and Response are partnering to distribute tests to the aging and disability networks. You may be able to get COVID-19 tests for free through your local Center on Independent Living.
• The Disability Information and Access Line (DIAL) can help people with disabilities connect with local COVID-19 testing options and help with ordering free at-home test kits.

Working with support providers

People with disabilities who have direct support providers can also help protect themselves from respiratory viruses in the following ways:

• Ask direct support providers if they are experiencing any symptoms of or have other reason to believe they might have a respiratory virus.
• Tell direct service providers to:
  • Open windows, use air filters and use other steps for cleaner air to reduce the amount of virus within indoor areas.
  • Wear a well-fitting mask over the nose and mouth.

What to know

• In addition to CDC’s Respiratory Virus Guidance, there are several specific considerations for people who are at higher risk for severe illness, including pregnant people.

Overview

Changes in the immune system, heart, and lungs during pregnancy can raise the risk of getting very sick from respiratory viruses.

Why prevention is important

Studies have shown that:

• The odds of admission to an intensive care unit with COVID-19 were 2.5 times higher in pregnant and recently pregnant women than they were for non-pregnant women of reproductive age. Learn more.
• Approximately 28 percent of reproductive-aged women hospitalized with influenza were pregnant across the 2010-2019 influenza seasons. Learn more.
• Getting a flu shot can reduce a pregnant person's risk of being hospitalized with flu by an average of 40 percent. Learn more.
• Flu, COVID-19, and RSV vaccination during pregnancy also reduce the risk of severe illness and hospitalization in babies during the first few months of life.
  • Over 75 percent of babies hospitalized with COVID-19 were born to women who did not receive the COVID-19 vaccine. Learn more.
  • Flu vaccination during pregnancy reduces the risk of flu hospitalization in infants younger than 6 months by about 40 percent. Learn more.
  • Clinical trials showed that giving the RSV vaccine to pregnant people reduced the risk of their babies being hospitalized for RSV by more than 50 percent. Learn more.

Making a plan

Reducing risk‎

If you are pregnant or recently had a baby, or if you spend time with someone who is pregnant or recently had a baby, using the prevention strategies described in CDC's Respiratory Virus Guidance are especially important. In addition, there are several specific considerations related to pregnancy

Immunizations

In addition to providing protection to the pregnant person, certain vaccines during pregnancy can help lower the risk for the baby after birth.

COVID-19

• COVID-19 vaccination is recommended for persons who are pregnant, might become pregnant, recently pregnant or breastfeeding.

Flu

• Flu vaccination can be administered at any time during pregnancy, before and during the flu season.
• Those who are or will be pregnant during flu season should receive inactivated influenza vaccine (IIV) or recombinant influenza vaccine (RIV). Live attenuated influenza vaccine (LAIV) is not recommended for use during pregnancy.

RSV

To prevent RSV-associated lower respiratory tract infection in infants, CDC recommends either:

• Administering RSVpreF (Abrysvo) vaccine to the pregnant person OR
• Administering RSV monoclonal antibody, nirsevimab (Beyfortus) to the infant.
• Most infants will not need protection from both products.
• RSVpreF (Abrysvo) vaccine is the ONLY Respiratory Syncytial Virus (RSV) vaccine approved for use during pregnancy to protect infants from RSV-associated lower respiratory tract infection.
  • The vaccine should be administered during weeks 32 through 36 of pregnancy (i.e., 32 weeks 0 days through 36 weeks 6 days).
  • In most of the continental United States, the vaccine should be administered from September through January.

Masks

• Note that better fitting masks (for example, N95 or KN95 respirators) are more effective at protecting you from inhaling germs than other types of masks are (for example, cloth masks or surgical/disposable masks).

Treatment

• The COVID-19 Treatment Guidelines Panel recommends against withholding treatment for COVID-19 from pregnant or lactating individuals because of theoretical safety concerns. For more information on the treatment of COVID-19 in pregnant people, see the NIH Treatment Guidelines on Special Considerations in Pregnancy.
• Flu antivirals are recommended for certain people at high risk for complications from flu, including pregnant people.
• To learn more about if treatment is right for you, speak with a healthcare provider.

What to know

• CDC's Respiratory Virus Guidance provides practical recommendations and information to help people lower health risks posed by a range of common respiratory viral illnesses, including COVID-19, flu, and RSV.

Overview

Each year, respiratory viruses are responsible for millions of illnesses and thousands of hospitalizations and deaths in the United States. In addition to the virus that causes COVID-19, there are many other types of respiratory viruses, including flu and respiratory syncytial virus (RSV). The good news is there are actions you can take to help protect yourself and others from health risks caused by respiratory viruses.

Prevention strategies

Core prevention strategies

CDC recommends that all people use core prevention strategies. These are important steps you can take to protect yourself and others:

• Stay up to date with immunizations
• Practice good hygiene (practices that improve cleanliness)
• Take steps for cleaner air
• When you may have a respiratory virus:
  • Use precautions to prevent spread
  • Seek health care promptly for testing and/or treatment if you have risk factors for severe illness; treatment may help lower your risk of severe illness

Additional prevention strategies

Additional prevention strategies you can choose to further protect yourself and others include:

• Masks
• Physical distancing
• Tests

Key times for prevention

All of the prevention strategies described in this guidance can be helpful to reduce risk. They are especially helpful when:

• Respiratory viruses are causing a lot of illness in your community.
• You or the people around you were recently exposed to a respiratory virus, are sick, or are recovering.
• You or the people around you have risk factors for severe illness.
  • Many factors can make it more likely for someone to become very sick from a respiratory virus. In addition to this guidance, there are several specific considerations for people with certain risk factors for severe illness (young children, older adults, people with weakened immune systems, people who are pregnant, and people with disabilities).
• You may not be aware of the things that can make others more vulnerable to serious illness. Using the core prevention strategies will provide a degree of protection regardless. If you are unsure about the health condition or risk status of those around you, the most protective option is choosing to use additional prevention strategies, like masking, physical distancing, and testing.

Notice‎

CDC offers separate, specific guidance for healthcare settings (COVID-19, flu, and general infection prevention and control). Federal civil rights laws may require reasonable modifications or reasonable accommodations in various circumstances. Nothing in this guidance is intended to detract from or supersede those laws.

What to know

• Treatment is a core prevention strategy to lower risk from respiratory viruses.
• Core prevention strategies are important steps you can take to protect yourself and others from respiratory viruses.

Recommendation

Treatment‎

Seek health care right away for testing and/or treatment if you believe you may have a respiratory virus (if you feel sick or tested positive for one) and you have risk factors for severe illness. If you have flu or COVID-19, treatment may be an option to make your symptoms less severe and shorten the time you are sick. Treatment needs to be started within a few days of when your symptoms begin.

How it works

Treatments for COVID-19 and for flu can lessen symptoms and shorten the time you are sick. They also may reduce the risk of complications, including those that can result in hospitalization. For people with risk factors for severe illness early treatment can mean having milder illness.

Steps you can take

Individuals can

• Know the treatment options for flu and COVID-19 before you get sick.
• Talk with a healthcare provider about planning to access treatment in advance of when you might need it.
• Talk with friends and family about how antiviral treatment could help reduce their chances of being hospitalized or dying from respiratory viruses like COVID-19 and flu.
• Take all treatments as prescribed.
• Talk to a healthcare provider about any questions you have about treatments.

Organizations can

• Share educational materials about respiratory virus treatment options:
  • Flu
  • COVID-19

• Provide employees with paid time off to seek treatment for a respiratory virus, as needed.

Key times for prevention

All of the prevention strategies described in this guidance can be helpful to reduce risk. They are especially helpful when:

• Respiratory viruses are causing a lot of illness in your community.
• You or the people around you were recently exposed to a respiratory virus, are sick, or are recovering.
• You or the people around you have risk factors for severe illness.

Chickenpox is a contagious disease caused by the varicella zoster virus. The virus spreads mainly by touching or breathing in the virus particles that come from chickenpox blisters, and possibly through tiny droplets from infected people that get into the air after they breathe or talk, for example. Symptoms of chickenpox include an itchy rash, fever, and tiredness. The disease can be serious – even fatal – especially for babies, adolescents, adults, pregnant women and people with a weakened immune system. The best protection against chickenpox is two doses of the chickenpox vaccine. Most people who get the vaccine will not get chickenpox. If a vaccinated person does get chickenpox, the symptoms are usually milder with fewer or no blisters (they may have just red spots) and mild or no fever.

Key Facts

• Chickenpox is a very contagious disease that is caused by varicella zoster virus.
• The classic symptom of chickenpox is a blister-like rash. You can have between 250 and 500 blisters all over your body.
• Before the vaccine was available, about 4 million people in the United States would get chickenpox each year.
• You can still get chickenpox if you have been vaccinated; however, the symptoms are usually milder, with fewer or no blisters (sometimes just red spots) and mild or no fever.
• CDC recommends two doses of chickenpox vaccine. If you previously got one dose, make sure to get a second one.

Chickenpox Transmission

It takes from 10 to 21 days after exposure to a person with chickenpox or shingles for someone to develop chickenpox. A person with chickenpox can spread the disease from 1 to 2 days before they get the rash, until all their chickenpox blisters have formed scabs.

Chickenpox Can Be Serious

Complications from chickenpox include infection of skin and soft tissues underneath, pneumonia, infection or inflammation of the brain, bleeding problems, and dehydration. Some people may be at high risk for complications, including infants, adolescents, adults, pregnant women, and those with a weakened immune system. Complications are not as common in otherwise healthy people who get chickenpox but can happen.

How It Spreads

The virus spreads mainly by touching or breathing in the virus particles that come from chickenpox blisters, and possibly through tiny droplets from infected people that get into the air after they breathe or talk, for example.

If You Get Chickenpox

Calamine lotion and colloidal oatmeal baths can help relieve an itchy chickenpox rash. Keep fingernails trimmed short to help prevent skin infections caused by scratching blisters. For fever, you can use non-aspirin medication, such as acetaminophen. Call a doctor if you’re at risk for severe chickenpox or you’re concerned about your symptoms.

The Link to Shingles

After you recover from chickenpox, the virus that causes this disease stays in your body. Later in life, the virus can reactive and cause shingles. If you have shingles, you can spread the virus to people who have never had chickenpox or never got the chickenpox vaccine. These people will develop chickenpox, not shingles.

Prevention Tips

• Chickenpox vaccine is very effective at preventing severe disease, complications, and death.
• Children, adolescents, and adults should get two doses of the chickenpox vaccine.
  • Children should get the first dose of chickenpox vaccine at 12 through 15 months old and a second dose at 4 through 6 years old.
  • People 13 years and older who have never had chickenpox or received chickenpox vaccine should get two doses at least 28 days apart. If you previously got one dose, make sure to get your second one.
• When you get vaccinated, you protect yourself and others in your community. This is especially important for people who cannot get vaccinated, such as those with a weakened immune system, babies less than 12 months old, or pregnant women.
• Some people should wait to get vaccinated or should not get vaccinated at all. This includes pregnant women and those with a severely weakened immune system.
• Talk to your doctor if you have questions about chickenpox or the chickenpox vaccine.

Most people get colds in the winter and spring, but it is possible to get a cold any time of the year. Symptoms usually include sore throat, runny nose, coughing, sneezing, headaches, and body aches. Most people recover within about 7-10 days. However, people with weakened immune systems, asthma, or conditions that affect the lungs and breathing passages may develop serious illness, such as pneumonia. Common colds are the main reason that children miss school and adults miss work. Each year in the United States, millions of people get the common cold. Adults have an average of 2-3 colds per year, and children have even more.

Key Facts

• Every year, adults have an average of 2–3 colds, and children have even more.
• Many viruses can cause colds, but rhinoviruses are most common. Infections spread through the air and close personal contact.
• There is no cure for a cold. To feel better, you should get lots of rest and drink plenty of fluids.
• Symptoms of a cold usually include sore throat, runny nose, coughing, sneezing, headaches, and body aches.
• To reduce your risk of getting a cold, wash hands often for at least 20 seconds with soap and water and avoid touching your face with unwashed hands.​

Protect Yourself and Others

Wash your hands often with soap and water for at least 20 seconds. If soap and water are not available, use an alcohol-based hand sanitizer that contains at least 60% alcohol. Viruses that cause colds can survive on your hands, and regular handwashing can help protect you from getting sick.

How to Feel Better

There is no cure for a cold. To feel better, you should get lots of rest and drink plenty of fluids. Over-the-counter medicines may help ease symptoms but will not make your cold go away any faster. Always read the label and use medications as directed. Talk to your doctor before giving your child nonprescription cold medicines, since some medicines contain ingredients that are not recommended for children.

When to See a Doctor

You should call your doctor if you or your child has one or more of these conditions: a temperature higher than 100.4°F, symptoms that last more than 10 days, or symptoms that are severe or unusual. If your child is younger than 3 months of age and has a fever, you should always call your doctor right away. Your doctor can determine if you or your child has a cold and can recommend therapy to help with symptoms.

Get Smart

When you have a cold, mucus fills your nose, causing runny nose, congestion, and mucus to drip down your throat (post-nasal drip), which can cause a sore throat and cough. This mucus helps wash the germs from the nose and sinuses. After two or three days, mucus may change to a white, yellow, or green color. This does not necessarily mean antibiotics are needed.

Prevention Tips

• Wash your hands often with soap and water. Wash them for at least 20 seconds, and help young children do the same. If soap and water are not available, use an alcohol-based hand sanitizer that contains at least 60% alcohol. Viruses that cause colds can stay on your hands, and regular handwashing can help protect you from getting sick.
• Avoid touching your eyes, nose, and mouth with unwashed hands. Viruses that cause colds can enter your body this way and make you sick.
• Stay away from people who are sick. Sick people can spread viruses that cause the common cold through close contact with others.
• Disinfect frequently touched surfaces, including objects such as toys and doorknobs.

COVID-19 is a respiratory disease caused by SARS-CoV-2, a coronavirus discovered in 2019. The virus spreads mainly from person to person through respiratory droplets produced when an infected person coughs, sneezes, or talks. Some people who are infected may not have symptoms. For people who have symptoms, illness can range from mild to severe. Adults 65 years and older and people of any age with underlying medical conditions are at higher risk for severe illness. People ages 5 years and older should get COVID-19 vaccines to prevent getting and spreading the illness. Everyone ages 16 and older can get a booster shot.

Key Facts

• The virus that causes COVID-19 can spread through respiratory droplets when an infected person coughs, sneezes, or talks.
• Symptoms may appear 2-14 days after someone is exposed to the virus and can include fever, chills, and cough.
• Some people who are infected may not have symptoms, which is why everyone should take everyday preventive actions.
• Anyone can have severe illness from COVID-19, especially older adults and people of any age with underlying conditions.

Social Distancing

Social distancing, also called “physical distancing,” is one of the best ways to avoid being exposed to COVID-19 and slowing its spread. To practice social or physical distancing, stay at least 6 feet (about 2 arms’ length) from other people, do not gather in groups, stay out of crowded places, and avoid mass gatherings.

Face Coverings Dos & Don'ts

CDC recommends wearing masks in public settings where other social distancing measures are difficult to maintain, such as grocery stores, pharmacies, and gas stations. Masks may slow the spread of the virus and help people who have the virus and do not know it from transmitting it to others.

Prevention Tips

• Get a COVID-19 vaccine if you are ages 5 or older. COVID-19 vaccines are safe, effective, and free!
• Wash your hands with soap and water for at least 20 seconds. If soap and water are not available, use a hand sanitizer that contains at least 60% alcohol.
• Avoid close contact with people outside your home. Stay at least 6 feet (about 2 arms length) from others.
• Wear a mask in public, even if you don’t feel sick. It will help protect others in case you are infected.
• Cover your coughs and sneezes with a tissue or the inside of your elbow. Throw used tissues in the trash and then wash your hands with soap and water for at least 20 seconds.
• Clean and disinfect frequently touched surfaces. This includes tables, doorknobs, light switches, countertops, handles, desks, phones, keyboards, toilets, faucets, and sinks.
• Stay home if you have symptoms such as fever, cough, shortness of breath.
• Seek emergency medical care if you develop severe symptoms, such as trouble breathing, chest pain, new confusion, inability to wake or stay awake, or pale, gray, or blue-colored skin, lips, or nail beds, depending on skin tone.​

Most people who get infected with non-polio enteroviruses do not get sick, or they only have mild illness, like the common cold. Symptoms of mild illness can include fever, runny nose, sneezing, cough, skin rash, mouth blisters, and body and muscle aches.

Three better-known non-polio enteroviruses are enterovirus D68 (EV-D68), enterovirus A71 (EV-A71), and coxsackie virus A6 (CV-A6). EV-D68 usually causes respiratory illness. EV-A71and CV-A6 are known to cause hand, foot, and mouth disease.

Infections with non-polio enteroviruses are common in the United States during summer and fall. A mix of enteroviruses circulates every year, and different types can be common in different years.

Key Facts

• Mild symptoms of enterovirus infection may include fever, runny nose, sneezing, cough, skin rash, mouth blisters, and body and muscle aches.
• Although rare, enteroviruses can sometimes cause more serious illness, like viral meningitis (infection of the covering of the spinal cord and brain) or acute flaccid myelitis (sudden onset of weakness in one or more arms or legs)
• Children with asthma are particularly at risk for severe symptoms from EV-D68 infection.
• There is no specific treatment for enterovirus infections, but most people recover completely.
• Important things you can do to stay healthy and protect others include washing your hands often with soap and water for at least 20 seconds, staying home when you’re sick, and cleaning and disinfecting frequently touched surfaces.

Protect Your Family

Wash hands often with soap and water for 20 seconds. Also, avoid touching your eyes, nose, and mouth with unwashed hands. Cover your coughs and sneezes with a tissue or shirt sleeve, not your hands. Clean and disinfect frequently touched surfaces.

Children with Asthma

Children with asthma are particularly at risk for severe symptoms from certain types of enterovirus infection, like EV-D68. Discuss and update your child’s asthma action plan with their doctor

Treating Enteroviruses

There is no treatment for enterovirus infections, but most people recover completely. People with mild illness caused by non-polio enterovirus infection typically only need to treat their symptoms. Talk to your doctor about the best way to control symptoms.

Enteroviruses in the United States

In the United States, people can get infected with non-polio enteroviruses at any time of the year. However, non-polio enterovirus infections are more common in the summer and fall.

Prevention Tips

• Wash hands often with soap and water for at least 20 seconds.
• Avoid touching eyes, nose, and mouth with unwashed hands.
• Avoid close contact, such as kissing, hugging, and sharing cups or eating utensils, with people who are sick.
• Cover your coughs and sneezes with a tissue or shirt sleeve, not your hands.
• Clean and disinfect frequently touched surfaces, such as toys, doorknobs, and cell phones, especially if someone is sick.
• Stay home when you are sick and keep sick children out of school.

Hand, foot, and mouth disease, or HFMD, is a contagious illness that is caused by different viruses. It is common in infants and children younger than 5 years old. However, older children and adults can also get HFMD. Symptoms include fever, mouth sores, and a skin rash. In the United States it is more common for people to get HFMD during summer and fall.

Key Facts

• Usually causes fever, painful sores in the mouth, and a rash on the hands and feet (sometimes with blisters).
• HFMD is a contagious disease.
• It mostly affects infants and children younger than 5 years old but people of any age can be infected.
• It has no specific treatment.
• Infection risk can be reduced by practicing good hygiene such as washing hands often

Preventing HFMD

Wash your hands often with soap and water for at least 20 seconds, especially after changing diapers, and help young children do the same; avoid close contact such as kissing, hugging, and sharing cups and eating utensils with people who have HFMD; and disinfect frequently touched surfaces and objects, such as toys and doorknobs, especially if someone is sick.

HFMD Treatment

There is no specific treatment for HFMD. Fever and pain can be managed with over-the-counter fever reducers and pain relievers, such as acetaminophen or ibuprofen. It is important for people with HFMD to drink enough fluids to prevent dehydration (loss of body fluids).

Is HFMD Serious?

HFMD is usually not serious. The illness is typically mild, and nearly all people recover in 7 – 10 days without medical treatment. Complications are uncommon. Rarely, an infected person can develop viral meningitis and may need to be hospitalized for few days. Other more rare complications can include polio-like paralysis or encephalitis (brain inflammation), which can be fatal.

Contagiousness

The viruses that cause HFMD can be found in an infected person's nose and throat secretions (saliva, sputum, or nasal mucus); blister fluid; and poop. People with HFMD are most contagious during their first week of illness. However, they may sometimes remain contagious for weeks after symptoms go away. Some people, especially adults, may not develop any symptoms, but they can still spread the viruses to others.

Prevention Tips

• Wash your hands often with soap and water for at least 20 seconds, especially after changing diapers.
• Avoid touching your eyes, nose, and mouth with unwashed hands.
• Avoid close contact such as kissing, hugging, and sharing cups and eating utensils with people who have HFMD.
• Disinfect frequently touched surfaces, including objects such as toys and doorknobs.

Rodents can carry dangerous pathogens, like hantavirus. Hantaviruses are a family of viruses found worldwide. In the United States, deer mice and other wild rodents can shed hantavirus in their urine, droppings, and saliva. People can become infected when they breathe in contaminated air. This can happen when cleaning rodent-infested areas in your home or vehicle – or when opening cabins, sheds, or outbuildings (like barns and storage facilities) that have been closed for the winter – which can stir up dust and dirt that contains urine, droppings, or nesting materials from an infected rodent. The virus can also be spread if an infected rodent bites someone. Scientists also believe people may be able to get the virus if they eat contaminated food or if they touch something that is contaminated and then touch their nose or mouth. In the United States, infection with hantavirus can cause hantavirus pulmonary syndrome (HPS). Symptoms of HPS usually first look like the flu, with fever, muscle aches, and fatigue. Later symptoms of HPS include shortness of breath, cough, and difficulty breathing. HPS can be fatal, so it’s important to take these prevention tips with you anywhere that rodents may live.

Key Facts

• There is no way to tell if a rodent is infected with hantavirus by its appearance; use safe cleaning practices every time you find rodent infestations.
• If you find rodent droppings, nesting material, or other signs of rodent activity, use disinfectant to wet down the area before cleaning it up. It is important that you do not stir up dust by sweeping or vacuuming up droppings, urine, or nesting materials. Wear gloves and be sure to wash your hands after you have finished cleaning.
• If you develop flu-like symptoms with difficulty breathing after coming into contact with rodents or a rodent-infested area, go to the doctor.

Sweeping Outdoors

Cleaning in and around your home can put you at risk for hantavirus infections if rodents have made it their home, too.

Cabin in the Woods

Opening or cleaning cabins that have been closed during the winter is a potential risk for hantavirus infections, especially in rural settings.

Pets Can Carry Hantavirus

Pet rats can also carry a type of hantavirus called Seoul virus, which caused illnesses in rats and their owners in 11 states in 2017.

Prevention Tips

Prevent hantavirus by limiting contact with rodents in your home, workplace, or campsite:

• Seal up holes and gaps in your home or garage where rodents may be coming in.
• Place traps in and around your home to decrease rodent infestation.
• Put human food and animal feed in containers that rodents cannot access (such as sealed containers made of metal or durable plastic).

Influenza (flu) is a common contagious viral respiratory illness that can affect the nose, throat, and lungs. Flu viruses spread mainly by droplets made when people with flu cough, sneeze or talk. Flu illness can vary from mild to severe. When severe, flu can result in hospitalization and even death. Some people are more likely to suffer serious flu complications, including older adults, pregnant people, young children and people with certain chronic health conditions. CDC recommends that everyone 6 months and older get an annual flu vaccine. Flu vaccination can prevent flu illness and its potentially serious complications. While flu vaccination varies in how well it works, an annual flu vaccination is the best way to protect against flu. However, if you get the flu, there are medications that can help treat it, and which are particularly important for some groups of people. Influenza antiviral drugs are prescription medications that can reduce severity and duration of flu illness, and also might prevent serious flu complications. CDC recommends influenza antiviral treatment for people who are very sick with flu and people with flu symptoms who are at higher risk of developing serious flu complications.

Key Facts

• The severity of flu seasons can differ substantially from season to season.
• You may be able to spread flu to someone else before you know you are sick, as well as while you are sick.
• Hundreds of thousands of people are hospitalized with flu each year.
• People with certain long-term health conditions, like asthma or diabetes, are at higher risk of serious flu complications.
• Take 3 steps to fight flu: get vaccinated, take everyday preventive actions, and take antiviral medicines if prescribed.

Are you at higher risk?

Certain people are at a greater risk of developing serious flu complications. These groups of people include: children younger than 5, adults 65 years of age or older, pregnant women, and people with certain chronic health conditions.

Prevention Tips

• An annual flu vaccination is the best way currently available to reduce the risk from flu and its potentially serious complications. As long as flu viruses are spreading, you can still benefit from a flu vaccine.
• Avoid people who are sick. Stay home when you are sick with flu for at least 24 hours after your fever is gone, except to get medical care or other necessities. Your fever should be gone without the need to use a fever-reducing medicine, such as acetaminophen.
• Avoid touching your eyes, nose, or mouth. Though less common than spread through droplets that come from the nose and mouth when people cough, sneeze, or talk, flu viruses can also when a person touches something that is contaminated with flu viruses and then touches their eyes, nose, or mouth.
• Wash your hands regularly with soap and water. If soap and water are not available, use an alcohol-based hand rub.
• Check with your doctor promptly if you are at higher risk of developing serious flu complications and you get flu symptoms. Your doctor may prescribe influenza antiviral drugs to treat your flu illness, which can lessen the severity of your illness, shorten the amount of time you are sick and help prevent serious flu complications.

Measles is a serious disease. It’s caused by a very contagious virus that spreads through coughing and sneezing. Symptoms include fever, runny nose, and red, watery eyes, followed by a rash of tiny, red spots that spread all over the body. Measles can lead to pneumonia, brain damage, deafness, and death. Thanks to the vaccine, measles is rare in the United States. But it’s still common in many other countries. Unvaccinated people are at risk of getting measles, especially when they travel abroad. They can bring the disease into the United States and infect others, which can lead to outbreaks.

Key Facts

• Measles is one of the most contagious diseases in the world. Anyone who is not protected is at risk, especially when traveling abroad.
• Measles vaccine works well. About 97 children out of 100 who get 2 doses of vaccine won’t get measles if they’re exposed to it.
• Since measles was eliminated in the U.S. in 2000, the annual number of people reported with measles ranged from a low of 37 in 2004 to a high of 667 in 2014.
• Before the measles vaccination program started in 1963, about 3-4 million people got measles each year in the United States.

A Healthy Baby

You can protect your children from measles by making sure they are vaccinated on time. The vaccine is usually given as part of a combination vaccine that protects against measles, mumps, and rubella. Children should get the first dose at 12 through 15 months of age, and the second dose at 4 through 6 years of age.

Measles and Travel

Measles is still common in many parts of the world. Unvaccinated Americans put themselves at risk when they travel abroad. They can bring the disease into the United States and infect others, which can lead to outbreaks. Make sure your vaccinations are up to date before you hit the road.

Measles Outbreaks

Measles outbreaks occur every year in the United States in communities where people are not vaccinated. People who get infected while traveling abroad bring the disease into these communities, where it can spread. Measles spreads very quickly among people who are not protected and can lead to severe complications.

Prevention Tips

• Get children vaccinated against measles. CDC recommends that children get two doses of measles vaccine—the first dose at 12 through 15 months of age, and the second dose at 4 through 6 years of age.
• Know your immunization status. Adults born during or after 1957 who haven’t had measles or have never been vaccinated should get at least one dose of measles vaccine. College students, international travelers, and healthcare personnel should get two doses, at least 28 days apart.
• Check before you travel. CDC recommends that infants 6 months of age and older, adolescents and adults are protected against measles before traveling abroad. Check with your healthcare provider to see if you or your child should get measles vaccine.
• Protect yourself and others. When you get measles vaccine, you protect yourself and others. This is very important for people who can’t get vaccinated, such as infants who are too young or people with specific health conditions.

Globally, pneumonia (an infection of the lungs) kills more children younger than 5 years old each year than any other infectious disease, such as HIV infection, malaria, or tuberculosis.

In the United States, 1.5 million people were diagnosed with pneumonia in an emergency department during 2018. Unfortunately, more than 40,000 people died from the disease that year in the United States. Most of the people affected by pneumonia in the United States are adults.

Vaccines and appropriate treatment (like antibiotics and antivirals) could prevent many of these deaths—globally and in the United States.

Key Facts

• Pneumonia is an infection of the lungs that can cause mild to severe illness in people of all ages.
• Viruses, bacteria, and fungi can all cause pneumonia.
• Common signs of pneumonia can include cough, fever, and trouble breathing.
• Bacteria and viruses that commonly cause pneumonia in the community are different from those in the healthcare settings.
• A common cause of bacterial pneumonia is Streptococcus pneumoniae (pneumococcus).

Pneumonia Prevention

Avoid people who are sick. If you are sick, stay away from others as much as possible to keep from getting them sick. Wash your hands regularly. Cough or sneeze into a tissue or into your elbow or sleeve. Clean and disinfect surfaces that are touched a lot. Limit contact with cigarette smoke or quit smoking. Take good care of medical conditions (like asthma, diabetes, or heart disease).

Who Can Get Pneumonia

Certain people are more likely to become ill with pneumonia: adults 65 years or older; children younger than 5 years old; people who have ongoing medical conditions (like asthma, diabetes or heart disease); and people who smoke cigarettes. Encourage friends and loved ones to make sure they are up to date with their vaccines.

Causes of Pneumonia

Viruses, bacteria, and fungi can all cause pneumonia. In the United States, common causes of viral pneumonia are influenza and respiratory syncytial virus (RSV). A common cause of bacterial pneumonia is Streptococcus pneumoniae (pneumococcus). However, clinicians are not always able to find out which germ caused someone to get sick with pneumonia.

Types of Pneumonia

Community-acquired pneumonia is when someone develops pneumonia in the community (not in a hospital). Healthcare-associated pneumonia is when someone develops pneumonia during or following a stay in a healthcare facility. Healthcare facilities include hospitals, long-term care facilities, and dialysis centers.

Prevention Tips

• Get vaccinated. Vaccines can help prevent infection by some of the bacteria and viruses that can cause pneumonia.
• Avoid people who are sick. If you are sick, stay away from others as much as possible to keep from getting them sick.
• Wash your hands regularly.
• Clean and disinfect surfaces that are touched a lot.
• Cough or sneeze into a tissue or into your elbow or sleeve.
• Limit contact with cigarette smoke or quit smoking.
• Manage and prevent conditions like diabetes, asthma, or heart disease.

Respiratory syncytial virus (RSV) is a contagious virus that affects the lungs and breathing passages. Most children get RSV infection by age 2, but you can get infected at any age and more than once in your life. The symptoms are usually similar to the common cold. Most people recover in a week or two, but others at high risk may get very sick and develop pneumonia or bronchiolitis (inflammation of the small airways in the lungs). There is no vaccine, but scientists are working to develop one. Until then, there are ways you can help prevent RSV infection.

Key Facts

• RSV usually causes mild, cold-like symptoms such as runny nose, decrease in appetite, coughing, sneezing, fever, and wheezing.
• Infants and older adults may develop severe infections from RSV, such as pneumonia or bronchiolitis.
• Most kids get an RSV infection by age 2. However, you can get an RSV infection at any age and more than once in your life.
• RSV spreads when an infected person coughs or sneezes, or shares cups and eating utensils with others.
• You can help protect yourself and others from RSV infections by washing your hands often with soap and water for at least 20 seconds.

RSV Can Be Serious

For most people, RSV infections are mild and clear on their own. But some people develop severe infections, such as pneumonia and bronchiolitis. People at high risk include very young infants, premature babies, young children with chronic lung or heart disease, older adults, and people with weakened immune systems.

Wash Your Hands Often

Wash your hands often with soap and water for 20 seconds, and help young children do the same. Proper hand hygiene can help protect you from getting RSV infection as well as prevent the spread of infection to others when you are sick.

Cover Your Cough and Sneeze

RSV can spread when an infected person coughs or sneezes. To help prevent germs from spreading, cover your coughs and sneezes with a tissue or your upper shirt sleeve, not your bare hands. Throw the tissue in the trash and wash your hands.

Avoid Sharing When Sick

You can get RSV infection if you share cups or eating utensils with others. You can also get infected if you touch surfaces, such as toys or doorknobs, that have the virus on them, then touch your eyes, nose or mouth.

Prevention Tips

• Wash your hands often with soap and water for at least 20 seconds, and help young children do the same.
• Cover your coughs and sneezes with a tissue or your upper shirt sleeve, not your bare hands. Throw the tissue in the trash and wash your hands.
• Avoid touching your eyes, nose, and mouth with unwashed hands.
• Avoid close contact, such as kissing, or sharing cups or eating utensils, with sick people.
• Clean and disinfect frequently touched surfaces, such as toys and doorknobs.