STL polyomavirus (STLPyV), also known as Saint Louis polyomavirus or human polyomavirus 11, is a non‑enveloped circular double‑stranded DNA virus in the Polyomaviridae family. First reported in 2013 from stool samples of children in Malawi, the Gambia and St. Louis, Missouri, it represents the eleventh human polyomavirus.
Explanation
STLPyV was first discovered in a stool sample from a healthy child in Malawi and soon after in children from The Gambia and St. Louis, Missouri. The virus is now included in the classification of human polyomaviruses and is considered the eleventh known species. Its circular genome is about 4.8 kilobases long and encodes the small and large T antigens, a unique alternatively spliced tumor antigen called 229T, and the structural proteins VP1, VP2 and VP3. Sequence variation among isolates can reach 5 %, and phylogenetically it is most closely related to MW polyomavirus. A distinctive feature of STLPyV is the 229T protein, which fuses portions of the small and large T antigens. Serologic surveys indicate that about 70 % of adults carry antibodies against STLPyV, consistent with infection occurring early in childhood. Active viral replication, measured by detection of viral DNA, is observed in roughly 1–2 % of children. The age distribution of seroprevalence suggests maternal antibody transfer followed by infection in the first years of life. To date, the virus has been detected mainly in stool samples from healthy and diarrheic children, and there is no convincing evidence linking STLPyV to human disease.
Noteworthy characteristics
– STLPyV is the eleventh known human polyomavirus and was first identified in Malawi, Gambia and St. Louis in 2013.
– The roughly 4.8 kb genome encodes typical polyomavirus proteins plus a novel alternatively spliced tumor antigen (229T).
– Serologic studies report about 70 % seroprevalence in adults, whereas detection of viral DNA occurs in only 1–2 % of children.
– STLPyV is most closely related to MW polyomavirus and belongs to the genus Deltapolyomavirus.
STLPyV appears to be a common commensal virus acquired in early childhood. Despite its high seroprevalence and unique genetic features, no human disease has been linked to it. Ongoing surveillance and molecular studies will help clarify its biology and its relationships with other polyomaviruses.
Related Terms: Malawi polyomavirus (MWPyV), Human Polyomavirus 6 (HPyV6), Human Polyomavirus 7 (HPyV7), New Jersey Polyomavirus (NJPyV), Deltapolyomavirus