Conventional Test Method:

Oral Polio Neurovirulence Test (Monkey intracerebral)

Alternative Test Method:

Name & Description:

Mutant Analysis by PCR and Restriction Enzyme Cleavage (MAPREC test)

PCR is used to measure the abundance of neurovirulent mutant sequences with a point mutation (472-C to 472-U) in the 5’-nontranslated RNA region of type 3 oral polio virus vaccine. Increased ratio of 472-U to 472-C in type 3 OPV RNA is associated with greater success of the vaccine. Any type 3 vaccine batch which fails MAPREC should not be tested further in monkeys, however if the vaccine is normal (i.e. negative), it must still be confirmed in a monkey neurovirulence test.

Validation Status:

WHO: Validated for type 3 oral polio virus vaccines

Regulatory Status:

No information

Effect or Potential Effect on Animal Use:


  • WHO Expert Committee on Biological Standardisation (1999) Forty-eighth Report, WHO Technical Report Series, No. 889. Geneva, Switzerland: World Health Organization (WHO).
  • WHO (2005) Final Report: IABS Scientific Workshop on Neurovirulence Tests of Live Virus Vaccines. Geneva, Switzerland: World Health Organization (WHO).
Information Last Reviewed:
May 2012