Viral hemorrhagic fevers (VHFs) are a group of illnesses caused by four families of viruses. These include the Ebola and Marburg, Lassa fever, and yellow fever viruses. VHFs have common features: they affect many organs, they damage the blood vessels, and they affect the body's ability to regulate itself. Some VHFs cause mild disease, but some, like Ebola or Marburg, cause severe disease and death.

VHFs are found around the world. Specific diseases are usually limited to areas where the animals that carry them live. For example, Lassa fever is limited to rural areas of West Africa where rats and mice carry the virus.

The risk for travelers is low, but you should avoid visiting areas where there are disease outbreaks. Because there are no effective treatments for some of these viral infections, there is concern about their use in bioterrorism.

Viral hemorrhagic fevers (VHFs) are a group of diseases that are caused by several distinct families of viruses. The term “viral hemorrhagic fever” refers to a condition that affects many organ systems of the body, damages the overall cardiovascular system, and reduces the body’s ability to function on its own. Symptoms of this type of condition can vary but often include bleeding, or hemorrhaging. Some VHFs cause relatively mild illness, while others can cause severe, life threatening disease. Most VHFs have no known cure or vaccine.

Although VHFs are caused by several families of viruses, these viruses share some common characteristics:

• They are RNA viruses, meaning viruses that have ribonucleic acid (RNA) as their genetic material. These viruses are the most common cause of emerging disease in people because RNA viruses change over time at a high rate.
• They are covered, or enveloped, in a lipoprotein outer layer, making it easier to destroy these viruses with physical (heat, sunlight, gamma rays) and chemical (bleach, detergents, solvents) methods.
• They naturally exist in animal or insect populations, referred to as host populations, and are generally restricted to the geographical areas where the host species live.
• They spread to people when a person encounters an infected animal or insect host. After the initial spread into the human population, some VHF viruses can continue to spread from person-to-person.
• Outbreaks of VHFs in people can be difficult to prevent since they can occur sporadically and cannot be easily predicted.

Several families of enveloped RNA viruses cause viral hemorrhagic fevers (VHFs).

Filoviruses include the Ebola viruses, which cause Ebola virus disease (EVD), and Marburg virus, which causes Marburg virus disease (MVD). Arenaviruses include Lassa virus, lymphocytic choriomeningitis virus (LCMV), and Lujo, Guanarito, Machupo, Junin, Sabia, and Chapare viruses. Bunyaviruses include Rift Valley fever (RVF) virus, Crimean-Congo hemorrhagic fever (CCHF) virus, and hantavirus. The flaviviruses include dengue virus, yellow fever virus, Omsk hemorrhagic fever virus, Kyasanur Forest disease virus, and Alkhurma hemorrhagic fever virus (also see the Dengue and Yellow Fever sections in this chapter).

More of the world’s population is at risk for VHFs

The number of viruses known to cause disease in humans around the globe is ever-increasing, and the way VHF viruses spread is likely to shift due to globalization, international travel, and climate change. Discovery and exploration of viruses and their hosts is necessary to limit global spread and disease burden.

Person-to-person transmission of some VHFs can occur

VHF viruses can spread to people when they come in contact with infected animals or insects. For many VHFs, person-to-person transmission can then continue, often through direct contact or in healthcare facilities without adequate infection control procedures. Further research on disease ecology can help scientists understand, and ultimately control, patterns and processes of virus transmission.

Confirmation of VHF cases can take time

Underdeveloped laboratories cannot rapidly diagnose and confirm illnesses, leading to delays in isolating infected people. Fast and accurate diagnostics are vital during outbreaks to confirm VHF cases, leading to faster isolation of cases and ultimately shorter, less severe outbreaks. Improving VHF diagnostic techniques to make them faster, more accurate, and easier to produce and use is an essential component to controlling these diseases.

Prevention of VHF outbreaks is difficult

Outbreaks of VHFs occur sporadically and irregularly, and their occurrence can be difficult to predict. Prevention is more difficult when the animal host is unknown or challenging to control (such as rodents or ticks). Strong risk communication and health education efforts are required, focusing on exposure prevention for communities and infection control for healthcare providers.

Availability of vaccines and treatments are limited

With limited effective vaccinations or drug treatments available, some VHFs are treated only with basic medical care, which is not always adequate to prevent virus spread and save lives. It is important to understand how the virus infects and spreads within the body to help guide the development of treatments and new strategies to protect against infection.

Viruses in the family Arenaviridae are generally spread by rodents, with each virus associated with one, or a few, closely related rodent species that serve as the virus’ natural reservoir. The types of rodents that spread arenaviruses are located across much of the world, including Europe, Asia, Africa, and the Americas. In some areas of the world, arenavirus infections in people are relatively common and can cause severe disease.

Discovery of Arenaviruses

Lymphocytic choriomeningitis virus (LCMV) was the first arenavirus identified. It was isolated in 1933 during a study of a St. Louis encephalitis epidemic. Although not the cause of the outbreak, LCMV was found to be a cause of nonbacterial meningitis. Since then, new arenaviruses have been discovered regularly.

How viruses in the Arenavirus family spread

While rodent hosts are chronically infected with an arenavirus, they do not appear to become ill. Most infections spread among adult rodents through scratches and bites, although for certain arenaviruses, the virus passes from mother to offspring during pregnancy. Arenaviruses are shed into the environment in the urine, saliva, or droppings of infected rodent hosts. People become infected by breathing in the virus after rodent urine, droppings, or nesting materials are stirred up, such as during cleaning. People can also get infected by touching their face after touching the virus, through the bites or scratches of infected rodents, and by eating contaminated food. In some instances, arenaviruses can spread to people when consuming infected rodents as a food source.

Person-to-person transmission can occur with certain arenaviruses, such as Chapare, Lassa, Machupo, and Lujo viruses. This type of transmission usually occurs when there is direct contact with the blood or other body fluids of infected individuals. Contact with contaminated objects, such as medical equipment, is also associated with spreading these viruses. Use of protective clothing and disinfection procedures while caring for a sick person can help prevent further spread of disease.

Old World/New World Arenaviruses

Arenaviruses are divided into two groups – New World and Old World viruses – based on genetic differences as well as where the viruses are geographically distributed. New World viruses are found in the Western Hemisphere — North and South America. They include Chapare virus, a severe or fatal hemorrhagic fever, found in Bolivia, as well as Guanarito virus found in Venezuela.

Old World viruses occur in the Eastern Hemisphere — Africa, Europe, and Asia. Lassa fever, which can cause mild to severe disease in people, is found in West Africa. Lujo, a fatal hemorrhagic fever, is found in southern Africa. LCMV, classified as an Old World arenavirus, is the only arenavirus found in both the Western and Eastern Hemisphere.

There are some arenaviruses – both New and Old World — that have been identified in host animals, but no human infection has been reported yet.

Bunyavirales is an order of single-strand, spherical, enveloped RNA viruses (formerly the Bunyaviridae family). The virus families in the Bunyavirales order that cause viral hemorrhagic fevers include Phenuiviridae, Arenaviridae, Nairoviridae, and Hantaviridae. Distribution of these viruses is determined by the distribution of the vector and host species.

Discovery of Bunyavirales viruses

Rift Valley fever virus (family Phenuiviridae) was first isolated in 1930 as part of a large outbreak among sheep in East Africa. This mosquito-borne virus is present in nearly all sub-Saharan African countries. Outbreaks in people and animals have occurred in several African countries and the Arabian Peninsula.

Crimean-Congo hemorrhagic fever (CCHF) virus (family Nairoviridae) was first recognized in the Crimean Peninsula (in the south of present-day Ukraine) in an outbreak among agricultural workers in the 1940s. The same virus was isolated in 1956 from a single patient in present day Democratic Republic of Congo, giving the virus its name. The virus is spread by infected ticks or livestock, and person-to-person transmission can also occur.

Hantaviruses (family Hantaviridae) were first observed in the early 1950s. These rodent-borne viruses are divided into two groups: Old World and New World. Old World hantaviruses are primarily found in Europe and Asia, and infection can cause Hemorrhagic Fever with Renal Syndrome (HFRS). New World hantaviruses are primarily found in North, Central, and South America. Infection with New World hantaviruses can cause hantavirus pulmonary syndrome (HPS).

How viruses in the Bunyavirales order spread

These viruses can spread by arthropods (such as mosquitoes, ticks, sand flies) or rodents, and can produce mild to severe disease in animals and people. Many of the viruses in the bunyavirales order (except phleboviruses) cannot spread from person-to-person. Secondary transmission of Crimean-Congo hemorrhagic fever has occurred in healthcare settings.

Preventing Bunyavirales infections

Prevention of Bunyavirales depends on the host reservoir and how the virus spreads. Prevention measures typically target rodent or insect exclusion activities, either by use of insect repellents, bed nets, and protective clothing, or by sealing up and setting traps in homes and other buildings when a rodent infestation is discovered.

Viruses in the family Filoviridae can cause severe hemorrhagic fever in people and nonhuman primates (such as monkeys and gorillas) and may spread in other animals, such as bats. Filoviruses are enveloped in a lipid (fatty) membrane and appear in several shapes. Each virion (complete, infective form of a virus) contains one molecule of single-stranded, negative-sense RNA.

Discovery of Filoviruses

In 1967, Marburg virus, the first discovered filovirus, was recognized when laboratory workers in Marburg, Germany and Yugoslavia developed hemorrhagic fever after handling tissues from green monkeys. The virus disappeared until 1975, when it emerged in South Africa in a traveler to Zimbabwe, and quickly spread to the traveler’s companion and a nurse caring for him. Since then, Marburg has emerged sporadically, including two large epidemics in Democratic Republic of Congo (DRC) from 1998-2000 and Angola from 2004-2005.

Ebola virus disease was first identified in 1976 when two consecutive outbreaks of fatal hemorrhagic fever occurred in different parts of Central Africa. The first outbreak occurred in DRC in a village near the Ebola River, giving the virus its name. The second outbreak occurred in what is now South Sudan, approximately 500 miles (850 km) away. Since then, six different species of ebolavirus have been discovered, four of which are known to cause disease in people.

How viruses in the Filovirus family spread

Filoviruses are zoonotic, meaning they are transmitted from animals to people. The reservoir host of Marburg virus is the African fruit bat, but further study is needed to determine if other species may also serve as hosts. Scientists have not determined the host for Ebola virus, although bats are likely involved and may be the reservoir.

Factors like population growth, encroachment into forested areas, and direct interaction with wildlife (such as bushmeat consumption) may contribute to the introduction of filoviruses into human populations. Once a person is infected, filoviruses can spread from person-to-person through direct contact with an infected person’s body fluids. Those at highest risk of infection are caretakers and healthcare providers who do not use appropriate personal protective equipment (PPE).

The Flaviviridae are a family of positive, single-stranded, enveloped RNA viruses. They are found in arthropods, (primarily ticks and mosquitoes), and can occasionally infect humans.

Members of this family belong to a single genus, Flavivirus, and cause widespread morbidity and mortality throughout the world. Some of the mosquitoes-transmitted viruses include: Yellow Fever, Dengue Fever, Japanese encephalitis, West Nile viruses, and Zika virus. Other Flaviviruses are transmitted by ticks and are responsible of encephalitis and hemorrhagic diseases: Kyasanur Forest Disease (KFD) and Alkhurma disease, and Omsk hemorrhagic fever.

The viruses that cause VHF are distributed over much of the globe. Each virus is associated with one or more nonhuman host or vector species, restricting the virus and the initial contamination to the areas inhabited by these species. The diseases caused by these viruses are seen in people living in or having visited these areas. Humans are incidental hosts for these enzootic diseases; however, person-to-person transmission of some viruses can occur. Specific viruses are addressed below.

Ebola and Marburg Virus Disease

People at greatest risk of EVD or MVD include family members, health care workers, or others who, without protective equipment, come into direct contact with infected patients or corpses; people who have come into contact or close proximity to bats (visiting bat caves); and people who have handled infected primates or carcasses. Additionally, sex partners of recent male EVD or MVD survivors may be at risk if they have had contact with virus-infected semen.

Countries where domestically acquired EVD cases have been reported and that should be considered areas where future epidemics could occur include Côte d’Ivoire, Democratic Republic of the Congo, Gabon, Guinea, Liberia, Republic of the Congo, Sierra Leone, South Sudan, and Uganda.

Typically, previous Ebola outbreaks had been limited in scope and geographic extent. However, in March of 2014, an outbreak of Ebola virus was detected in a rural area of Guinea near the border with Liberia and Sierra Leone. By June of 2014, cases were reported in all 3 countries and across many districts. The outbreak was the largest and most complex Ebola epidemic ever reported. Additional cases occurred in Nigeria, Senegal, Mali, Spain, the United Kingdom, Italy, and the United States, after infected people traveled from West Africa.

Countries with confirmed human cases of MVD include Angola, Democratic Republic of the Congo, Kenya, Uganda, and possibly Zimbabwe. Four cases of MVD have occurred in travelers visiting caves harboring bats, including Kitum Cave in Kenya and Python Cave in Maramagambo Forest, Uganda. Miners in the Democratic Republic of the Congo and Uganda have also acquired Marburg virus infection from working in underground mines harboring bats.

Reston virus is believed to be endemic to the Philippines but has not been shown to cause human disease.

Lassa Fever and Other Arenaviral Diseases

Arenaviruses are maintained in rodents and transmitted to humans, except Tacaribe virus, which was found in bats but has not been reported to cause disease in humans. Most infections are mild, but some result in hemorrhagic fever with high death rates. Arenaviruses may be divided into 2 categories, Old World (eastern hemisphere) and New World (western hemisphere).

• Old World arenaviruses (and the diseases they cause) include Lassa virus (Lassa fever), Lujo virus, and LCMV (meningitis, encephalitis, and congenital fetal infection in normal hosts; severe disease with multiple organ failure in organ transplant recipients). Lassa fever occurs across rural West Africa, with hyperendemic areas in parts of Sierra Leone, Guinea, Liberia, and Nigeria. Lujo virus has been described in Zambia and the Republic of South Africa during a health care-associated outbreak.
• New World arenaviruses (and the diseases they cause) include Junin (Argentine hemorrhagic fever), Machupo (Bolivian hemorrhagic fever), Guanarito (Venezuelan hemorrhagic fever), Sabia (Brazilian hemorrhagic fever), and Chapare virus (single case in Bolivia).

Reservoir host species are Old World rats and mice (family Muridae, subfamily Murinae) and New World rats and mice (family Muridae, subfamily Sigmodontinae). These rodent types are found worldwide, including Europe, Asia, Africa, and the Americas. Virus is transmitted through inhalation of rodent urine aerosols, ingestion of rodent-contaminated food, or by direct contact of broken skin or mucosa with rodent excreta. Risk of Lassa virus infection is associated with peridomestic rodent exposure, where inappropriate food storage increases the risk for exposure. Several cases of Lassa fever have been confirmed in international travelers staying in traditional dwellings in the countryside. Health care-associated transmission and close family member infection with Lassa, Lujo, and Machupo viruses occurs through droplet spread and direct contact.

Rift Valley Fever and Other Bunyaviral Diseases

RVF primarily affects livestock, causing stillbirths and high mortality in neonatal cattle, sheep, and goats. In humans, RVF virus infection causes fever, hemorrhage, encephalitis, and retinitis. RVF virus is endemic to sub-Saharan Africa. Sporadic outbreaks have occurred in humans in Comoros, Egypt, Madagascar, Mali, Mauritania, Senegal, South Sudan, Sudan, and Uganda. Large epidemics occurred in Kenya, Somalia, and Tanzania in 1997–1998 and 2006–2007; Saudi Arabia and Yemen in 2000; Madagascar in 1990 and 2008; Botswana, Mauritania, Namibia, and South Africa in 2010; and Niger in 2016–2017. RVF virus is transmitted to livestock by mosquitoes, while people become infected more frequently through direct contact with clinically affected animals or their body fluids, including slaughter or consumption of infected animals.

CCHF is endemic to areas of Africa and Eurasia where ticks of the genus Hyalomma are found, including South Africa, the Balkans, the Middle East, Russia, and western China, and particularly to Turkey, Afghanistan, Iran, and Pakistan. The first human cases were reported in Spain in 2016. Primarily associated with livestock, Hyalomma ticks will also bite humans. Livestock and other hosts may develop CCHF viremia from tick bites but do not develop clinical disease. CCHF virus is transmitted to humans by infected ticks or by direct handling and preparation of fresh carcasses of infected animals, usually domestic livestock. Human-to-human transmission can occur through droplet or direct contact.

Hantaviruses cause hantavirus pulmonary syndrome (HPS) and hemorrhagic fever with renal syndrome (HFRS). The viruses that cause HPS are present in the New World; those that cause HFRS occur worldwide. The viruses that cause both HPS and HFRS are transmitted to humans through contact with urine, feces, or saliva of infected rodents. Travelers staying in rodent-infested dwellings are at risk for HPS and HFRS. Human-to-human transmission of hantavirus has been reported only with Andes virus in Chile and Argentina. The first reported case of imported Andes virus in the United States occurred in 2018 in a traveler returning from Chile and Argentina.

Some of the VHF viruses (filoviruses, arenaviruses, CCHF virus) spread by direct contact with symptomatic patients, body fluids, or cadavers, or through inadequate infection control in health care settings. In community settings, disease transmission occurs when a person (without proper skin and mucous membrane protection) comes into direct physical contact with the blood or other infectious body fluids of patients in the acute phase of disease or who have died.

Zoonotic sources of VHF virus exposure include:

• Livestock, via slaughter or consumption of raw meat from infected animals or unpasteurized milk (CCHF, RVF, Alkhurma viruses)
• Rodents or insectivores, via direct contact with the animal or inhalation of, or contact with, materials contaminated with rodent excreta (arenaviruses, hantaviruses)
• The Egyptian fruit bat (Rousettus aegyptiacus), the natural reservoir for Marburg virus; bats are suspected reservoir species for the viruses within the genus Ebolavirus
• Mosquitoes (RVF virus) and ticks (CCHF, Omsk, Kyasanur Forest disease, Alkhurma viruses)

After recovery from acute EVD or MVD, the virus or its RNA persists in some specific body fluids of convalescent patients. Ebola virus RNA has been detected in breast milk up to 21 days after the onset of the disease and in vaginal secretions up to 33 days after onset. Ebola virus and Marburg virus have been cultured from ocular aqueous humor at 2 and 3 months after disease onset, respectively. Evidence suggests that Ebola and Marburg viruses can be sexually transmitted from a male survivor to his partner months after onset of disease. In pregnant women with EVD, there can be in utero transmission of Ebola virus to the fetus.

Signs and symptoms vary by disease, but in general, patients with VHF present with abrupt onset of fever, myalgias, headache, and prostration, followed by coagulopathy with a petechial rash or ecchymoses and sometimes overt bleeding in severe forms. Gastrointestinal symptoms (diarrhea, vomiting, abdominal pain) are commonly observed. Vascular endothelial damage leads to shock and pulmonary edema, and liver injury is common.

Findings associated with specific viruses include renal failure (hantavirus); ecchymoses and bruises (CCHF virus); pharyngitis, retrosternal pain, hearing loss in adults and anasarca in newborns (Lassa virus); retinitis and partial blindness (RVF virus); and spontaneous abortion and birth defects (Lassa virus and LCMV). Laboratory abnormalities include elevations in liver enzymes, initial drop in leukocyte count, and thrombocytopenia. Because the incubation period may be as long as 21 days, patients may not develop illness until returning from travel; therefore, a thorough travel and exposure history is critical.

US-based clinicians should notify local health authorities immediately of any suspected cases of VHF occurring in patients residing in the United States. For laboratory testing requests, notify the local or state health department. To notify the CDC directly regarding any patients requiring evacuation to the United States, contact the CDC Emergency Operations Center at 770-488-7100. Appropriate personal protective equipment is indicated for any patients where Lassa, Lujo, South American arenaviruses, or CCHF virus infection is suspected, and includes droplet and contact precautions.

Whole blood or serum may be tested for virologic (RT-PCR, antigen detection, virus isolation) and immunologic (IgM, IgG) evidence of infection. Tissue may be tested by immunohistochemistry, RT-PCR, and virus isolation. Postmortem skin biopsies fixed in formalin and blood collected by cardiac puncture within a few hours after death can be used for diagnosis. Consider collection of an oral swab from deceased cases when an alternative sample cannot be collected.

Special handling procedures are required when submitting blood and other body fluid specimens for diagnostic testing.

The mainstay of treatment for VHFs is early, aggressive, supportive care directed at maintaining effective intravascular volume and correcting electrolyte imbalances. Ribavirin is effective if given early in the course of disease for treating Lassa fever and other Old World arenaviruses, New World arenaviruses, and potentially CCHF, but it is not approved by the Food and Drug Administration (FDA) for these indications.

There is no proven specific therapy for EVD. Several experimental immune therapy and antivirals treatments are under investigation. EVD patients may also have concomitant malaria infection. As such, empiric use of antimalarial therapy should be considered when rapid diagnostic testing is not immediately available. In general, NSAIDs such as ibuprofen and diclofenac are not recommended because of their antiplatelet activity.

There is no FDA-approved vaccine for any of the VHFs. Experimental Ebola vaccines are under development, including a recombinant vesicular stomatitis virus-based vaccine and a chimpanzee adenovirus-based vaccine. However, these investigational products are in the early stages of product development and are not yet available. Investigational vaccines exist for Argentine hemorrhagic fever and RVF; neither vaccine is approved by FDA or commercially available in the United States.

The risk of acquiring VHF is very low for international travelers. Travelers at increased risk for exposure include those engaging in animal research, and health care workers and others who, without adequate personal protection, provide care for patients in the community, particularly where outbreaks of VHF are occurring.

Prevention should focus on avoiding unprotected contact with sources of infection: people suspected of having VHF and hosts/vector species in endemic countries. Travelers should not visit locations where outbreaks are occurring, avoid contact with rodents and bats, and avoid blood or body fluids of livestock in RVF- and CCHF-endemic areas. To prevent vectorborne diseases, travelers should use insecticide-treated bed nets and wear insect repellent.

For VHFs that can be transmitted person to person (EVD, MVD, Lassa Fever, CCHF), early identification and isolation of ill travelers, consistent implementation of basic infection control measures, and prompt notification of public health authorities are the keys to prevent secondary transmission. Early identification strategies include eliciting a travel history from all patients who present for care and posting signs and placards asking patients with recent international travel to self-identify. Those patients with recent international travel who have symptoms consistent with any VHF should be promptly isolated by placing them in a private room or a separate enclosed area with a private bathroom or covered bedside commode. To minimize disease transmission risk, only essential health care providers wearing personal protective equipment should evaluate a patient and provide care. Prompt notification of the facility’s infection control program as well as state and local health departments is also key.

If you are living or working in areas where outbreaks of viral hemorrhagic fevers (VHFs) are known to occur, you should be familiar with how VHFs spread. These viruses spread from an animal or insect host to people. Once circulating within a person, some VHFs can spread from person-to-person, often through contact with blood or body fluids.

The likelihood of contracting any VHF is considered extremely low, even for international travelers. However, exposure can occur when traveling to an affected area, especially if your work brings you into direct contact with the blood or body fluids of infected people or animals, or objects contaminated with infected body fluids. If you have been in an area where VHFs are present and you experience fever or other symptoms, you should be evaluated by a healthcare provider.

Before you leave

• Assemble a travel health kit containing basic first aid and medical supplies, including:
  • Thermometer
  • Household disinfectant
  • Alcohol-based hand rubs for hand hygiene
  • Supply of surgical masks and disposable gloves (if your agency does not provide them and you may be in close contact with suspected VHF patients).
• Educate yourself and others who may be traveling with you about relevant VHFs. Visit specific disease sites at www.cdc.gov.
• Ensure your routine vaccines are up to date. Visit your healthcare provider at least 4 weeks before travel for additional travel vaccines, medications, and advice. For information on health recommendations for international travel, see CDC Travelers’ Health.
• Review your health insurance plan and consider additional insurance that covers medical evacuation in the event of illness. Information about medical evacuation services can be found at the U.S. Department of State.
• Identify in-country healthcare resources in advance of your trip.

While in an area where VHFs have been reported

• Observe barrier techniques when in close contact with a person or animal suspected of being infected with a VHF. This includes wearing protective gowns, gloves, masks, and eye protection (e.g., eyeglasses) or face shields. Sterilization or proper disposal of needles and equipment, and proper disposal of patient excretions, are also important to prevent the spread of infection.
• Wash hands carefully and frequently with soap and water (or use alcohol-based hand rubs when soap and water are not available).
• Avoid contact with sick or dead animals, especially primates.
• Do not eat “bushmeat” (meat from wild animals, including primates or rodents).

If you think you have a VHF infection or symptoms compatible with a VHF

Visit a healthcare provider immediately if you or someone you know becomes ill with fever or develops symptoms such as chills, muscle aches, nausea, vomiting, or rash while in an area where VHFs are present. The nearest U.S. Embassy or Consular Office can help you find a provider in the area if you are still abroad. Try and identify these resources in advance. Limit contact with others and avoid all other travel while you are sick.

After you return to the U.S.

Monitor your health for 21 days if you are returning from a VHF-affected area, even if you did not have any known exposures to infected people, animals, or contaminated objects. If you did have a possible exposure, notify a healthcare provider immediately and monitor your health for 21 days past the exposure.

If you become ill, consult a healthcare provider immediately and tell them about your recent travel and any potential exposures. Inform the provider of your symptoms prior to going to the office or emergency room so arrangements can be made to prevent transmission to others in the healthcare setting, if necessary.