Detection of Antibodies Directed Towards Zika Virus by PRNT<<Return to Laboratory
Serological detection of neutralizing antibodies directed towards Zika (ZIKV) virus by Plaque Reduction Neutralization Test (PRNT).
- Zika virus infection
Serum. Minimum volume of 250 µL required.
2 mL screw cap tubes.
Store samples refrigerated or frozen until shipped for testing. Ship frozen samples on dry ice, and refrigerated samples on wet ice.
Shipping of specimens shall be done by a TDG certified individual in accordance with TDG regulations. For additional information regarding classification of specimens for the purposes of shipping, consult either Part 2 Appendix 3 of the TDG Regulations or section 3.6.2 of the IATA Dangerous Goods Regulations as applicable.
For additional guidance on the transport of infectious substances in other languages, please click on the link below.
Suspected Zika virus infection and relevant travel history. Submitted samples will first be analysed by the Viral Zoonoses Diagnostic Laboratory by Zika IgM and IgG ELISA to determine if the patient has developed anti-flavivirus antibodies. Samples that are reactive can be further analysed for the presence of neutralizing antibodies. Samples that are ELISA non-reactive (negative) will not be tested by PRNT.
Completed Viral Zoonoses requisition including sender laboratory name, address and telephone number. Patient name and / or identifier (specimen reference number), date of birth, test(s) requested, collection date of specimen, date of on-set of symptoms, type of specimen, and clinical and travel history of patient.
Submission of acute and convalescent samples collected >14 days apart will help distinguish acute versus past infection and potentially eliminate low level cross reactivity from past flavivirus virus infections.
As ZIKV is a flavivirus, serologic tests may detect antibodies to other flaviviruses such as dengue, West Nile, and Yellow Fever viruses (including vaccine recipients). Confirmation of ZIKV, therefore, requires detection of viral RNA by RT-PCR or confirmatory PRNT serologic testing, which is laborious and time-consuming. Confirmatory testing requires neutralizing IgG antibody production, which may appear later than IgM. Patients whose serum samples are IgM and/or IgG positive and are also shown to contain ZIKV-specific antibodies by a PRNT assay are confirmed cases of viral infection. It should be noted that individuals previously infected with or vaccinated against flaviviruses may exhibit cross reactivity in PRNT tests as well, and the test results may be difficult to interpret. Since dengue virus and ZIKV are transmitted by the same types of mosquitoes, co-infections with these viruses are possible. As noted above, if antibody is present against both of these viruses or other related flaviviruses, it may be difficult to determine the virus responsible for current versus past infections.
21 calendar days