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Hantavirus pulmonary syndrome (HAN-tuh-vy-rus PUL-mo-nar-ee SIN-drome) is a lung disease that causes respiratory distress (breathing difficulty) and, in some cases, death. Hantavirus, the virus that causes the disease, is carried by rodents.
Hantavirus pulmonary syndrome (HPS) is a potentially deadly disease that attacks the lungs. A family of viruses * called hantavirus causes HPS. These viruses live in rodents but do not make them sick. The Sin Nombre virus hantavirus causes most HPS in the United States, but some cases have come from the Bayou, the New York, and the Black Creek Canal viruses.
Rodents, usually mice and rats, shed hantavirus in their saliva, urine, and droppings. Humans catch the virus when they disturb dried droppings (for example, by sweeping) and inhale the particles that are sent into the air. People can also contract hantavirus by touching an infected animal or its droppings and then touching their own nose or mouth. Eating food or drinking water contaminated by rodent droppings is another way to contract the infection. Rodent bites, although rare, can also spread the disease.
HPS is rare. Health authorities first recognized the disease in the United States in 1993, and the Centers for Disease Control and Prevention (CDC) recorded only 690 reported cases through January 2016, with 235 fatalities. Most cases in the United States appear in the Southwest and in places that have large rodent populations. Outside of North America, numerous individual cases and small clusters of HPS cases have been reported in Argentina, Bolivia, Brazil, Chile, Ecuador, Panama, Paraguay, Uruguay, and Venezuela. Large outbreaks have been rare and have usually been associated with human disturbance and land-use changes or with unusual environmental events such as increased rainfall or periodic bamboo flowering.
People of every age, sex, and race can contract HPS, but it is not contagious and cannot be spread by sneezing, coughing, kissing, or having other bodily contact.
The first symptoms of HPS usually appear one to five weeks after a person has been exposed to the virus. HPS can be difficult to diagnose because the early signs, such as fever, tiredness, and body aches, are similar to those of the flu. About half of the people who catch HPS may also experience dizziness, chills, nausea, vomiting, abdominal * pain, or headaches.
From two to five days after the first symptoms, a person infected with hantavirus starts coughing and experiences shortness of breath. The disease quickly becomes more severe, and people who do not receive immediate treatment may become extremely ill and go into shock * , needing intensive care in a hospital.
A doctor may suspect HPS if a person with flulike symptoms complains about difficulty breathing, especially if the person has been exposed to rodents or rodent droppings. To confirm the diagnosis, the doctor uses blood tests to see if the person has developed antibodies * to a strain * of hantavirus. Chest x-rays or ultrasound * images can help the doctor check the condition of a person's heart and lungs.
HPS is a serious disease, and someone who has it needs treatment in a hospital's intensive care unit. There the patient might be given fluids, have blood pressure monitored, and have a tube inserted in the throat to make it easier to breathe. Because a virus causes HPS, antibiotics do not work against it, although an antiviral drug may help some patients.
Doctors know more about the disease and are quicker to get patients into treatment. The earlier people with HPS receive help, the better their chances of survival. Recovery from HPS is fairly fast, although patients may feel worn out for several months.
There is no vaccination * available for HPS. The best way to avoid contracting the virus is to get rid of possible sources of infection, which means avoiding woodpiles and other places where rodents live outdoors and keeping homes and workplaces free of mice and rats. Experts also recommend sealing holes where rodents can enter (they can squeeze through spaces as small as 0.25 inches [6.35 millimeters] in diameter) and wearing a mask and gloves when cleaning out areas with rodent droppings.
See also Zoonoses: Overview
Núñez, Jonathan J., et al. “Hantavirus Infections among Overnight Visitors to Yosemite National Park, California, USA, 2012.” Emerging Infectious Diseases 20, no. 3 (March 2014). http://wwwnc.cdc.gov/eid/article/20/3/13-1581_article (accessed July 15, 2015).
Centers for Disease Control and Prevention. “Facts about Hantaviruses.” http://www.cdc.gov/hantavirus/pdf/hps_brochure.pdf (accessed July 15, 2015).
MedlinePlus. “Hantavirus Infections.” U.S. National Library of Medicine. https://www.nlm.nih.gov/medlineplus/hantavirusinfections.html (accessed July 15, 2015).
Centers for Disease Control and Prevention. 1600 Clifton Rd., Atlanta, GA 30333. Toll-free: 800-311-3435. Website: http://www.cdc.gov (accessed July 15, 2015).
World Health Organization (WHO). Ave. Appia 20, 1211 Geneva 27, Switzerland. Telephone: 41 22 791 2111. Website: http://www.who.int (accessed July 15, 2015).
* viruses (VY-rus-sez) are tiny infectious agents that can cause infectious diseases. Viruses can reproduce only within the cells they infect.
* abdominal (ab-DAH-mih-nul) refers to the area of the body below the ribs and above the hips that contains the stomach, intestines, and other organs.
* shock is a serious condition in which blood pressure is very low and not enough blood flows to the body's organs and tissues. Untreated, shock may result in death.
* antibodies (AN-tih-bah-deez) are protein molecules produced by the body's immune system to help fight specific infections caused by microorganisms, such as bacteria and viruses.
* strain is a subtype of an organism, such as a virus or bacterium.
* ultrasound also called a sonogram, is a diagnostic test in which sound waves passing through the body create images on a computer screen.
* vaccination (vak-sih-NAY-shun), also called immunization, is giving, usually by an injection, a preparation of killed or weakened germs, or a part of a germ or product it produces, to prevent or lessen the severity of the disease caused by that germ.