Testing timing guide
Hantavirus PCR Test Timing Checker: When to Test
Use this education-only checker to compare a possible exposure date, a symptom onset date, and the testing windows clinicians may consider. Hantavirus testing should be interpreted by medical or public-health professionals, not used as a home rule-out tool.
Quick Facts
Main question
Timing
Exposure date and symptom onset both matter
Methods
PCR + IgM/IgG
RNA detection and antibody testing answer different questions
Early negative
Repeat?
Specimens within 72h of symptoms may need follow-up testing
Best route
Clinician
Ask a medical or public-health professional
Hantavirus PCR Test Timing Checker
Enter Exposure and Symptom Dates
PCR Test Timing Checker
Enter a last possible exposure date and, if relevant, a first symptom date. This gives education-only timing context for what to ask a clinician or public-health team.
Andes symptom window
May 14, 2026 - Jun 21, 2026
CDC Andes timing is 4-42 days after exposure.
If no symptoms
Monitor
Testing choices for contacts are managed by clinicians or health departments.
If symptoms appear
Call first
Contact a medical professional or local public-health authority promptly.
No symptom onset date entered.
For an exposed but asymptomatic person, a single early negative test should not be treated as a self-clearance result. Follow the monitoring plan from the health department or clinician managing the exposure.
This checker is not a diagnostic tool. If you have symptoms after a possible hantavirus or Andes virus exposure, contact a medical professional or local public-health authority.
PCR vs Serology: What Each Test Tells You
Different Tests, Different Timing Limits
Hantavirus testing usually involves specialised laboratories. Clinicians and public-health teams decide whether PCR, rRT-PCR, IgM/IgG serology, repeat testing, or additional investigation is appropriate.
PCR / rRT-PCR
Looks for: Viral RNA
Most time-sensitive. CDC notes Andes rRT-PCR sensitivity may be reduced later in illness.
IgM serology
Looks for: Recent immune response
Used for laboratory confirmation. If negative within 72h of symptoms, repeat testing may be needed.
IgG serology
Looks for: Antibody evidence
Helps interpret infection history with clinical and exposure context.
Exposure monitoring
Looks for: No infection by itself
For Andes virus contacts, public-health monitoring runs through the 42-day window.
| Method | Looks for | Timing note |
|---|---|---|
| PCR / rRT-PCR | Viral RNA | Time-sensitive. CDC notes Andes rRT-PCR sensitivity may be reduced later in illness. |
| IgM serology | Recent immune response | Used for laboratory confirmation. If negative within 72h of symptom onset, repeat testing after 72h may be needed. |
| IgG serology | Antibody evidence | Helps interpret infection history with clinical and exposure context. |
| Exposure monitoring | No infection by itself | For Andes virus contacts, public-health monitoring runs through the 42-day window. |
Early Negative Test: What It Means
Do Not Use It as Self-Clearance
A negative result early in illness can be hard to interpret. CDC guidance says that if IgM and IgG antibody tests are negative from a specimen collected within 72 hours of symptom onset, a second specimen collected after 72 hours may be needed to rule out New World hantavirus infection.
This is why exposed contacts may still need symptom monitoring even after an initial negative test. Testing decisions should stay with the clinician or public-health team managing the exposure.
When to Test After Exposure
Exposure First, Symptoms Next, Testing Through Official Channels
Day 0 after exposure
Record the last possible exposure date. For MV Hondius contacts, this sets the 42-day monitoring window used by public-health teams.
Days 4-42
CDC lists 4-42 days as the Andes virus symptom timing window. Fever, gastrointestinal symptoms, cough, or breathing changes should trigger medical or public-health contact.
First 72h of symptoms
Early serology can be incomplete. A negative IgM/IgG result from this period may need a later specimen after 72 hours.
Later in illness
Andes rRT-PCR sensitivity may be reduced later in illness. Serology, repeat testing, and clinical context become important for interpretation.
MV Hondius Testing
Screening During Monitoring
UKHSA reported PCR testing for returning passengers under assessment, including people without symptoms, so that positive cases could be detected early.
Testing rules can differ by country. Contacts should follow the instructions from the authority managing their monitoring.
Exposure to Care Workflow
Use the Right Page for the Right Question
Frequently Asked Questions
Sources
- About HantavirusCenters for Disease Control and Prevention · 2024-05-13
- About Andes VirusCenters for Disease Control and Prevention · 2026-05-07
- Clinical Overview of HantavirusCenters for Disease Control and Prevention · 2024-05-13
- Interim Guidance for Public Health Assessment and Management of People with Potential Exposure to Andes VirusCenters for Disease Control and Prevention · 2026-05-14
- What you need to know about the hantavirus outbreak linked to the Dutch cruise shipUK Health Security Agency · 2026-05-12