Human papillomavirus (HPV) in men in Bulgaria: hidden burden and vaccination gaps

Background

Human papillomavirus (HPV) is a major public health concern because of its high prevalence and oncogenic potential. Men contribute substantially to transmission, often remaining asymptomatic and enabling silent spread. Men who have sex with men (MSM) are at higher risk of persistent infection. While vaccination strategies have traditionally focused on females, many countries are adopting gender-neutral approaches. In Bulgaria, HPV vaccination has recently been introduced for boys up to age 14, while access beyond this age remains self-funded.

Methods

A retrospective study was conducted at Checkpoint Sofia, the only sexual health center in Bulgaria, offering PCR genotyping for 14 high-risk HPV types. Between April 2024 and April 2026, 91 male patients were tested and subsequently consulted with an infectious disease specialist regarding management and prevention. Demographic, clinical, and virological data were analyzed.

Results

Most participants were aged 30–40 years (65%), followed by those under 30 (18%). MSM contacts were reported by 62%, and prior sexually transmitted infections by 66%. Genital warts were present in 48%, oral and genital lesions in 5%, and 26% required invasive interventions. Notably, 46% were asymptomatic. Multiple high-risk HPV types (≥3) were detected in 24% of cases. The most common genotypes were HPV 16 (56%), HPV 18 (29%), and HPV 31 (25%). Following counseling, 93% (85/91) of patients opted for self-funded Gardasil 9 vaccination.

Conclusions

A high burden of oncogenic HPV types was identified, including among asymptomatic men, highlighting their role as a reservoir for transmission. The high uptake of vaccination after counseling suggests strong acceptability but also underscores financial barriers. Expanding publicly funded, gender-neutral HPV vaccination strategies is essential to reduce transmission and HPV-related disease at the population level.

Key messages

• Men are a silent reservoir of high-risk HPV, often asymptomatic yet oncogenic.

• Targeted counselling boosts vaccine uptake, exposing unmet prevention needs and access gaps worldwide.