Standardization of B19 IgG ELISA to study the seroepidemiology of parvovirus B19 in North Indian voluntary blood donors

Abstract

Backgound and Objectives:Parvovirus B19 (B19) being a non-enveloped DNA virus is hence thermo-stable to the current methods of viral inactivation. Therefore transfusion of blood or its component from a viremic donor to non-immune recipients may result in transfusion-transmitted B19 infection with occasional sinister complications. The serologically naïve blood donor population in our country has not been studied. Hence a study was designed to find the sero-status of B19 virus in normal voluntary blood donor population (relatives of recipients) as an indirect measure of the susceptibility to B19 in north Indians together with seroepidemiology of B19.Methods:An in-house anti-B19 IgG ELISA was standardized using cloned, baculovirus expressed, and purified VP1/VP2 capsid proteins as antigen. Anti-B19 IgG antibodies in sera (diluted 1:400) of 1000 healthy voluntary blood donors (18-60 years; mean 30.5 years) were analyzed and their epidemiologic data were documented.Results:A total of 399 (39.9%) donors were seropositive for B19 virus. Seroprevalence was higher in males than females (44% vs 27%) and it increased with increasing age (P<0.01). Socioeconomically, B19 IgG antibody positivities were 61.8%, 61.1%, and 44.4% in low, medium, and high income groups respectively with unskilled laborers having higher seroprevalence in low (48.5%) and middle (58.7%) income group (P<0.05). Housing conditions revealed B19 seroprevalence as 42.6% in donors living in small houses compared to 20.4% in larger houses (P<0.01) but no difference with religion.Conclusions:Seroprevalence to B19 in normal voluntary blood donors was low leaving a large proportion of north Indians susceptible to B19 infection.