Hantavirus symptoms.
Hantavirus symptoms appear 1–8 weeks after exposure to aerosolized rodent excreta. The illness has two phases: a flu-like prodrome for 3–5 days, then a sudden cardiopulmonary or renal crisis. The prodrome is indistinguishable from influenza — the differentiator is exposure history.
Phase 1 — prodrome (days 1–5)
- Fever, often above 38.5 °C
- Deep muscle aches, especially thighs, hips, and lower back
- Headache, severe fatigue
- Nausea, vomiting, abdominal pain
- No prominent respiratory or urinary symptoms yet
Routine respiratory panels do not detect hantavirus. If you have flu-like symptoms plus recent rural travel, rodent exposure, or contact with an MV Hondius case, tell your clinician explicitly to consider hantavirus.
Phase 2 — cardiopulmonary phase (HPS form)
- Cough, often dry
- Shortness of breath, often abrupt and severe
- Pulmonary edema visible on chest X-ray
- Hypotension, tachycardia
- Rapid progression to ARDS, sometimes within hours
This is a medical emergency. Survival depends on getting to a tertiary ICU with ventilator and ECMO capability before respiratory failure.
Phase 2 — renal phase (HFRS form)
- Oliguria (reduced urine output)
- Flank pain, lumbar tenderness
- Petechiae, conjunctival injection
- Hypotension; some patients enter shock
- Recovery phase with diuresis and gradual return of kidney function
What to do
- If you have only the prodrome: contact your primary care clinician same-day.
- If you develop shortness of breath, chest tightness, or rapid heart rate: go to an emergency department.
- Always mention rodent exposure or recent travel to an endemic region.
- If you were on the MV Hondius, follow the 45-day surveillance protocol from your national public health authority.
Frequently asked
What are the first symptoms of hantavirus?
The first symptoms appear 1–8 weeks after exposure and look like a bad flu: fever, chills, deep muscle aches especially in the thighs and lower back, headache, fatigue, nausea, vomiting, and abdominal pain. There is no respiratory or kidney involvement at this stage.
How long after exposure do hantavirus symptoms appear?
The incubation period is typically 1–8 weeks, with most cases presenting at 2–4 weeks. Symptoms can appear as early as 9 days or as late as 56 days after exposure to aerosolized rodent excreta.
When should I go to the ER?
Go immediately if you develop shortness of breath, chest tightness, or rapid heart rate after a flu-like prodrome — especially if you had recent rodent exposure or travel to an endemic region. Tell the ER team explicitly to consider hantavirus. Early ICU care dramatically improves survival.
Are hantavirus symptoms different in children?
Children present similarly to adults but may show fewer abdominal symptoms and faster progression to respiratory distress. The prodrome can be subtle — children with HPS sometimes look only mildly ill until they decompensate suddenly.
Can hantavirus look like COVID or flu?
Yes — the early prodrome is indistinguishable from influenza or COVID-19. The differentiating clue is exposure history (rodents, rural travel, recent MV Hondius contact). Routine respiratory panels do not include hantavirus testing; you must request it.
Disclaimer. Symptom information is for general education only and is not medical advice. If you have symptoms, contact a clinician or your national public health authority.