Authors : Hathshya M. Munasigha, Ananda Amarasinghe, Neelika G. Malavige and Nalini Sathiakumar
Abstract: To determine whether self-reported history of previous varicella infection is an accurate predictor of immunity to varicella. A population-based cross-sectional study of 1258 participants was conducted in Colombo District, Sri Lanka. Using interviewer-administered questionnaire, information on sociodemographic characteristics and previous history of varicella infection were obtained. A commercial enzyme-linked immunosobent assay kit was used to detect varicella zoster virus antibody IgG from serum samples. Self-reported varicella infection by the overall study group and by subgroups of adolescents, adults and women of childbearing age had a high positive predictive value (overall group, 92%; subgroups, 91-95%) for immunity to VZV. Whereas, a negative history of varicella infection was not an accurate predictor of nonimmune status, the negative predictive values were low for the overall group (76%) and subgroups (64-84%). For persons who are not at high risk of varicella infection, a positive history of varicella may be used to indicate positive immune status in lieu of serological testing. For those at high risk for varicella infection and a negative history of varicella infection, serological testing is required to determine immune status. For all those determined to the non-immune by serological testing, varicella vaccine should be offered.
Hathshya M. Munasigha, Ananda Amarasinghe, Neelika G. Malavige and Nalini Sathiakumar, 2019. Predictive Value of Self-reported History of Varicella in Colombo District, Sri Lanka. International Journal of Tropical Medicine, 14: 5-10.