Merkel Cell Polyomavirus Is Associated with Anal Infections in Men Who Have Sex with Men

Background: Viral infections of the anal/rectal tract of men who have sex with men (MSM) have been poorly studied. Methods: In total, 158 swab samples (81 anal/rectal, 65 throat/oral and 12 urethral) were collected from 126 MSM. DNA was isolated and subjected to real-time PCR assays for the detection of the sexually transmitted (ST) pathogens Chlamydia trachomatis, Neisseria gonorrhoeae and Mycoplasmas ssp, human papillomavirus (HPV) and six human polyomaviruses (HPyVs
JCPyV, BKPyV, Merkel cell PyV&ndash
MCPyV-, HPyV-6, HPyV-7 and HPyV-9). Results: C. trachomatis (31/126, 24.6%) and M. genitalium (30/126, 23.8%) were the most frequently detected ST pathogens. Thirty-one/126 (24.6%) patients were positive for at least one HPyV. The significantly (p &lt
0.05) prevalent HPyV in the anal tract was MCPyV, which was amplified in 27/81 (33.3%) samples, followed by HPyV-6, which was amplified in 6/81 (7.4%) swabs. Coinfections with MCPyV and C. trachomatis or Mycoplasmas were found in 4/21 (19.0%) and 5/21 (23.8%) anal/rectal swabs, respectively. Three/4 MCPyV-C. trachomatis coinfected patients were symptomatic. Conclusions: Based on the high prevalence of MCPyV in the anal/rectal swabs from MSM patients and on the well-known oncogenic properties of MCPyV, sexual transmission and possible involvement of HPyVs in the pathogenesis of diseases of the anal canal should be further studied.