Zoonotic infection of Brazilian primate workers with New World simian foamy virus

Abstract

Simian foamy viruses (SFVs) are retroviruses present in nearly all nonhuman primates (NHPs), including Old World primates (OWP) and New World primates (NWP). While all confirmed human infections with SFV are from zoonotic transmissions originating from OWP, little is known about the zoonotic transmission potential of NWP SFV. We conducted a longitudinal, prospective study of 56 workers occupationally exposed to NWP in Brazil. Plasma from these workers was tested using Western blot (WB) assays containing NWP SFV antigens. Genomic DNA from blood and buccal swabs was analyzed for the presence of proviral SFV sequences by three nested PCR tests and a new quantitative PCR assay. Exposure histories were obtained and analyzed for associations with possible SFV infection. Ten persons (18%) tested seropositive and two persons were seroindeterminate (3.6%) for NWP SFV. Six persons had seroreactivity over 2–3 years suggestive of persistent infection. All SFV NWP WB-positive workers reported at least one incident involving NWP, including six reporting NWP bites. NWP SFV viral DNA was not detected in the blood or buccal swabs from all 12 NWP SFV seroreactive workers. We also found evidence of SFV seroreversion in three workers suggestive of possible clearance of infection. Our findings suggest that NWP SFV can be transmitted to occupationally-exposed humans and can elicit specific humoral immune responses but infection remains well-controlled resulting in latent infection and may occasionally clear.

Foamy virus zoonotic infections

“…In another published study, 56 people occupationally exposed to NWM in Brazil were screened for NWM SFV infection using both antibody (Western blot) and PCR assays [ 89 ]. In this longitudinal study 18% (10/56) of the people sampled were NWM SFV antibody positive at the initial time point, but none of these seropositive people were SFV PCR positive.…”

An Immunodominant and Conserved B-Cell Epitope in the Envelope of Simian Foamy Virus Recognized by Humans Infected with Zoonotic Strains from Apes

“…studies carried out worldwide (1,2). Human exposure to SFV from New World monkeys (NWM) leads to SFV-specific seroreactivity, with undetectable blood SFV DNA (3,4). Almost all SFV-infected individuals were bitten or injured by a NHP, and no case of human-to-human SFV transmission has yet been reported (1,2,5).…”

Seroprevalence of viral infections in captive rhesus and cynomolgus macaques

“…Therefore, the antibody status of animals is determined before purchase and use in experimentation (SIV, STLV, BV and SRV/D) and/or is continuously monitored (BV). However, the detection of BV-specific antibodies is challenging since antibody responses may develop only months after infection and antibody titers in infected animals maybe very low or undetectable at certain times after infection (Olson et al, 1991;Ward and Hilliard, 2002;Wolfensohn and Gopal, 2001). We had previously used an inhouse Enzyme Linked Immunosorbent Assay (ELISA) based on lysates from cells infected with herpesvirus papio 2 or a modified anti-HSV ELISA kit (Enzygnost ® Anti-HSV/IgG, Siemens) (Pöhlmann et al, 2017) to detect antibodies against BV in the colony studied here with negative results.…”