An exanthem is a widespread rash and usually refers to those occurring in children. Historically, six "classical" infectious childhood exanthems have been recognized; numbers were coined around 1905, from First to Sixth Diseases. Four of these six classic exanthemous diseases are caused by viruses:

  • First Disease: measles virus (Rubeloa)
  • Third Disease: rubella virus (German measles)
  • Fifth Disease: parvovirus B19 (Erythema infectiosum)
  • Sixth Disease: Human Herpes Viruse 6 (roseola infantum)

The General Virology Laboratory (GVL) provides testing for these and other exanthemous viruses for diagnostic and surveillance purposes. Many are common childhood illnesses, as well as vaccine preventable diseases (VPD). The GVL is a CDC reference center for viral VPD testing. Please visit the viral Vaccine Preventable Diseases page for further details on available testing for measles, rubella, and varicella zoster virus. If smallpox virus infection is suspected, contact the Wadsworth Center Biodefense Laboratory. See the Wadsworth Center Viral Encephalitis Laboratory for coxsackievirus and HHV6 testing on CSF from patients with encephalitis.

Test Menu

Virus Real-Time PCR Molecular Serotyping* Viral Culture Preferred Sample Type(s) for Exanthemous Virus All Validated Sample Types for Molecular Testing** Note
Coxsackievirus X X X NPS or combined NPS/OPS URS, CSF, rectal swabs, and stool  
Human Herpes Virus 6 X X   OPS or tissue OPS, CSF, and tissue Testing for HHV-6 in patients without CNS illness requires prior authorization
Parvovirus B19 X** X   Serum Serum  

*Available for epidemiologic surveillance and upon request for special circumstances; the latter requires an approved Non-permitted Laboratory Test Form.

** This particular test or the submission of a different specimen type will require an approved Non-Permitted Laboratory Test Form form prior to testing.

URS-upper respiratory swab; NPS-nasopharyngeal swab; OPS-oropharyngeal swab

Collection Guidance


  • Must be collected and sent in liquid viral transport media
  • Flocked swabs are preferred. Do NOT use cotton or calcium alginate-tipped or wooden shafted swabs
  • Volume: at least 1.0 mL; minimum volume: 0.35 mL

Stool and urine

  • Collect in a sterile container. Do NOT add viral transport media
  • Volume for urine: at least 1.0 mL; minimum volume: 0.35 mL;
  • Volume for stool: place up to 4 spoonfuls


  • Collect 7 to 10 ml of blood into a marble-topped tube or a plastic yellow-topped serum separator tube. Spin samples to separate serum. Dispense to a sterile, labeled tube for shipment at room temperature.
  • Alternatively, collect 3 to 5 ml of blood into a labeled lavendar-topped tube. Gently mix blood with anticoagulant (not heparin) in tube to prevent clotting.


  • Fresh/frozen tissue is preferred.
  • Tissues stored in formalin are discouraged as they are often inhibitory to PCR and produce inconclusive results; submission requires special authorization.

Shipping Guidance

  • Specimens must be shipped overnight (or hand couriered)
  • Specimens should arrive Monday through Friday
  • Specimens must remain cold (on frozen ice packs – NO wet ice) or frozen on dry ice (suggested minimum weight 2 kg or 5 lbs of dry ice) during shipment and upon arrival in the laboratory
  • Specimens must be accompanied by either a hand written Infectious Disease Requisition (IDR) or an electronically generated and printed Remote Order Requisition
  • Specimens must be packaged and shipped properly by appropriately trained personnel. Please refer to the following for guidance:
  • International Air Transport Association (IATA)
  • New York State Department of Transportation
  • Specimens that are sent through UPS, Fed Ex, or other commercial courier services should be sent overnight to the address on the right hand side.