ERAP2 and HIV-1 infection: A recent report presented evidence that ERAP2 haplotype A conferred protection during the Black Death [16], while haplotype B predicts better prognosis in HIV-1 infection and lowers risk of chronicity in Hepatitis C [51], suggesting that bacterial and viral pathogens may elicit distinct ERAP expression profiles, as shown for haplotype B (ERAP2/Iso3) expression [17,47].