Shortness of breath, rapid heart rate, low blood pressure, sudden severe back or abdominal pain, or reduced urine output after possible rodent exposure — go to an emergency department immediately and tell them about the exposure.
Incubation period
Symptoms typically appear 1 to 8 weeks after exposure; most cases develop within 2-4 weeks. Because the early phase is flu-like, the link to a rodent encounter from weeks ago is easily missed. If you've cleaned an enclosed shed, cabin or barn, mention it during examination.
HPS — Hantavirus Pulmonary Syndrome
Phase 1 · Early (days 1–5)
Fever, fatigue and severe muscle pain concentrated in thighs, hips, back and shoulders. Often accompanied by headache, chills, dizziness, nausea, vomiting, diarrhea and abdominal pain. About half of patients report headache.
Phase 2 · Cardiopulmonary (days 4–10)
Cough develops, followed rapidly by shortness of breath as fluid accumulates in the lungs. The transition can happen within hours — it is critical. Hospitalization, oxygen and usually intensive care are required. This is the life-threatening phase of HPS.
Recovery
Surviving patients regain lung function within weeks. Fatigue and reduced exercise tolerance can persist for months.
HFRS — Hemorrhagic Fever with Renal Syndrome
Febrile phase (3–7 days)
Sudden fever, chills, severe headache, back and abdominal pain, blurred vision. Flushing and "flame" appearance on face, neck and chest; conjunctival redness and small skin hemorrhages (petechiae).
Hypotensive phase (hours to 2 days)
Sudden drop in blood pressure, tachycardia, hypoxia. Shock and clinical deterioration can develop in this phase.
Oliguric phase (3–7 days)
Significant decrease in urine output, acute kidney failure and hemorrhagic findings. Medical management is critical; dialysis may be needed.
Diuretic phase (weeks)
Urine output resumes, often excessively (several liters per day). Fluid and electrolyte balance must be monitored.
Recovery
Recovery can take months. Permanent kidney damage occurs in some patients; long-term follow-up is recommended after severe cases.
How hantavirus is diagnosed
Diagnosis begins with clinical suspicion in patients with rodent exposure history. Confirmation is by serology (IgM/IgG antibodies) or PCR. The early phase is often confused with flu, dengue or leptospirosis; conveying exposure information to the clinician accelerates diagnosis.
When to see a doctor
If you develop fever, severe muscle pain or unexplained fatigue within 8 weeks of cleaning an enclosed area where rodents may have been present, see a doctor and mention the possible exposure. Don't wait for breathing or kidney symptoms — early supportive care dramatically improves outcomes.
Frequently asked questions
Is hantavirus contagious between humans?▾
Most strains are not. Andes virus (South America) is the only known exception with documented person-to-person transmission. For other strains, infection requires contact with rodent urine, droppings or saliva.
How long after exposure should I worry?▾
Symptoms typically appear 1–8 weeks after exposure. If you remain symptom-free 8 weeks after a possible exposure, the risk is essentially zero.
Is there a treatment?▾
There is no specific antiviral treatment. Care is supportive — oxygen, ICU, dialysis if needed. Early supportive care is the strongest predictor of survival.
What's the survival rate?▾
HPS has a fatality rate around 30–40% in the Americas. HFRS varies from below 1% (Puumala virus, Europe) up to 10–15% (Hantaan virus, East Asia). Early hospital care significantly improves outcomes.
Can I get hantavirus from my pet rat or hamster?▾
No. Hantaviruses circulate in wild rodents (deer mice, voles, certain field rats). Domesticated pet rodents from breeders are not a known reservoir.
This page is informational and does not replace medical advice. For symptoms, contact your doctor or local emergency service.