PARV4 prevalence, phylogeny, immunology and coinfection with HIV, HBV and HCV in a multicentre African cohort

Abstract

<ns4:p> <ns4:bold>Background:</ns4:bold> The seroprevalence of human parvovirus-4 (PARV4) varies considerably by region. In sub-Saharan Africa, seroprevalence is high in the general population, but little is known about the transmission routes or the prevalence of coinfection with blood-borne viruses, HBV, HCV and HIV. </ns4:p> <ns4:p> <ns4:bold>Methods:</ns4:bold> To further explore the characteristics of PARV4 in this setting, with a particular focus on the prevalence and significance of coinfection, we screened a cohort of 695 individuals recruited from Durban and Kimberley (South Africa) and Gaborone (Botswana) for PARV4 IgG and DNA, as well as documenting HIV, HBV and HCV status. <ns4:italic> <ns4:bold> </ns4:bold> </ns4:italic> </ns4:p> <ns4:p> <ns4:bold>Results:</ns4:bold> Within these cohorts, 69% of subjects were HIV-positive. We identified no cases of HCV by PCR, but 7.4% were positive for HBsAg. PARV4 IgG was positive in 42%; seroprevalence was higher in adults (69%) compared to children (21%) (p&lt;0.0001) and in HIV-positive (52%) compared to HIV-negative individuals (24%) (p&lt;0.0001), but there was no association with HBsAg status. We developed an on-line tool to allow visualization of coinfection data ( <ns4:ext-link xmlns:ns3="http://www.w3.org/1999/xlink" ext-link-type="uri" ns3:href="https://purl.oclc.org/coinfection-viz">https://purl.oclc.org/coinfection-viz</ns4:ext-link> ). We identified five subjects who were PCR-positive for PARV4 genotype-3. <ns4:italic>Ex vivo</ns4:italic> CD8+ T cell responses spanned the entire PARV4 proteome and we propose a novel HLA-B*57:03-restricted epitope within the NS protein. </ns4:p> <ns4:p> <ns4:bold>Conclusions:</ns4:bold> <ns4:italic/> This characterisation of PARV4 infection provides enhanced insights into the epidemiology of infection and co-infection in African cohorts, and provides the foundations for planning further focused studies to elucidate transmission pathways, immune responses, and the clinical significance of this organism. </ns4:p>