Hantavirus Pulmonary Syndrome (HPS) Symptoms, Causes and Risk Factors
What Are Symptoms of HPS?
HPS has three phases. The first phase is the "incubation" phase, when the virus is inhaled into the lungs, ingested by immune cells, and then transported via the blood to other organs. This phase lasts for 2 to 3 weeks, and the patient has no symptoms.
The second phase lasts 2 to 8 days and includes rapid development of fever, dry cough, body aches, headaches, diarrhea, and abdominal pain. Heart and lung failure can develop during this phase. Blood vessels become leaky and lead to collection of fluid in the lungs, bleeding, and failure of the heart to pump. The combination of these changes leads to shock failure of several organs, and often death.
In the third phase, there are alternating periods of high and low urine production.
In the fourth and final phase, patients who remain alive have improving symptoms and recovery of organ function. Complete recovery occurs over several weeks. The symptoms of HPS seem to resolve as rapidly and dramatically as its onset.
Key symptoms and signs to watch for (especially with a history of rodent exposure) include:
- Fever greater than 101◦F, chills, body aches, headaches
- Nausea and vomiting and abdominal pain
- New rash (faint red spots)
- A dry cough followed by rapid onset of breathing difficulty
What Causes HPS?
HPS is acquired via inhalation of virus particles from contact with infected rodents. Transmission is only known to occur from rodents to humans. To date, there are no confirmed reports of human-to-human transmission. There are several strains of hantavirus that are responsible for various syndromes of illness.
What Are Risk Factors?
Environmental factors: Rural populations with potential exposure to wild rodents are at risk. There are cases of patients developing HPS without any obvious exposure to rodents, but it is possible that patients may not recognize their rodent exposure. In these cases, an awareness of other cases of HPS in the area and suspicious signs and symptoms should alert one to seek help and clinicians to establish early diagnosis and treatment
Note: Any adult with exposure to the virus can develop hantavirus infection. It does not only affect those with weak immune systems.
When to See Your Doctor
If you have unexplained fever, body aches, abdominal pain, diarrhea, headaches, dry cough or severe breathing difficulty, you should see a healthcare provider. This is especially true if you are exposed to large rodent populations and their secretions (urine, saliva and/or feces).