Accuracy and repeatability of a micro plaque reduction neutralization test for vaccinia antibodies.

Abstract

The detection of neutralizing antibodies against vaccinia virus is a valuable tool for the investigation of previous smallpox vaccination. Compulsory smallpox vaccination ended in Brazil during the early 1970s, although the vaccine was available until the late 1970s. The threat of smallpox as a biological weapon has called the attention of public health authorities to the need for an evaluation of the immune status of the population. Based on our previous experience with a micro plaque reduction neutralization test (PRNT) for the evaluation of yellow fever immunity, a similar test was developed for the detection and quantification of vaccinia neutralizing antibodies. A cross-sectional study to test the repeatability and validity of plaque reduction neutralization test (PRNT) for vaccinia antibodies was performed in 182 subjects divided into two categories: subjects above 31 years old and the other > or = 35 years old. Cases were subjects considered to have been vaccinated with vaccinia virus if they declared vaccination history or evidenced vaccination marks. The assay is carried out in 96-well plates, provides results within 30 h, is easily performed, has good sensitivity (92.7%) and specificity (90.8), excellent repeatability (ICC 0.89 (0.88; 0.92)) and is thus suitable for use in mass screening of a population's antibody levels.

• Authors: Maria Beatriz J Borges, Sayuri E M Kato, Clarissa R A Damaso, Nissin Moussatché, Marcos da Silva Freire, Sonia Regina Lambert Passos, Jussara Pereira do Nascimento
• Journal: Biologicals : journal of the International Association of Biological Standardization (Biologicals) Vol. 36 Issue 2 Pg. 105-10 (Mar 2008) ISSN: 1045-1056 [Print] England
• PMID: 17892944 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antibodies, Viral
• Smallpox Vaccine

Topics

• Adolescent
• Adult
• Aged
• Animals
• Antibodies, Viral (analysis, biosynthesis)
• Cell Line
• Child
• Chlorocebus aethiops
• Cross-Sectional Studies
• Humans
• Middle Aged
• Neutralization Tests (methods, standards)
• Reproducibility of Results
• Smallpox Vaccine (immunology)
• Vaccinia (diagnosis, immunology, virology)
• Vaccinia virus (growth & development, immunology)
• Viral Plaque Assay (standards)