Ø  Introduction

The epidemiology of human papillomavirus (HPV) in women has been well documented. Less is known about the epidemiology of HPV in men. Laia Bruni and his colleagues published a research study titled "Global and regional estimates of genital human papillomavirus prevalence among men: a systematic review and meta-analysis" in "The Lancet Global Health" (Impact Factor: 34.3). The aim of this study is to provide updated global and regional pooled overall, type-specific, and age-specific prevalence estimates of genital HPV infection in men.

Ø  Methods

The study searched Embase, Ovid MEDLINE, and the Global Index Medicus for studies published between Jan 1, 1995, and June 1, 2022. Inclusion criteria were population-based surveys in men aged 15 years or older or HPV prevalence studies with a sample size of at least 50 men with no HPV-related pathology or known risk factors for HPV infection that collected samples from anogenital sites and used PCR or hybrid capture 2 techniques for HPV DNA detection. The study extracted only data on mucosal α-genus HPVs. Global and regional age-specific prevalences for any HPV, high-risk (HR)-HPV, and individual HPV types were estimated using random-effects models for meta-analysis and grouped by UN Sustainable Development Goals geographical classification.

Ø  Conclusion

Almost one in three men worldwide are infected with at least one genital HPV type and around one in five men are infected with one or more HR-HPV types. The findings show that HPV prevalence is high in men over the age of 15 years and support that sexually active men, regardless of age, are an important reservoir of HPV genital infection. These estimates emphasize the importance of incorporating men in comprehensive HPV prevention strategies to reduce HPV-related morbidity and mortality in men and ultimately achieve the elimination of cervical cancer and other HPV-related diseases.

Ø  Results

1.     The study identified 5685 publications from database searches, of which 65 studies comprising data from 44769 men were included in the systematic review and meta-analysis.

Figure 1 PRISMA flow diagram

2.   The 65 studies provided data from 35 countries, with 16 countries having more than one study. 36 (55%) studies were from high-income countries and only six (9%) studies were from low or lower-middle-income countries. The estimated overall HPV prevalence (of any type) among men was 31% (95% CI 27–35). The overall prevalence of HR-HPV was 21% (95% CI 18–24). Globally, HPV-16 was the most frequent HR-HPV type at 5% (95% CI 4–7) followed by types 51 (3%, 3–4), 52 (3%, 2–3), 59 (2%, 2–3), and 18 (2%, 2–3). HPV-6, a non-HR-HPV type, was the second most prevalent HPV type globally (4%, 95% CI 3–5).

Table 1 Meta-analyses of studies reporting the prevalence of any HPV, HR-HPV, HPV-16, and HPV-6 by region and income classification

Figure 2 Pooled prevalence of HR-HPV types, HPV-6, and HPV-11 in men by region

3. The age-specific prevalence curves show a high prevalence of HPV in young adult men, which remains high throughout adulthood. Prevalence was highest in people aged 25–29 years for any HPV (35%, 95% CI 30–41), HR-HPV (24%, 19–29), and HPV-16 (6%, 5–9). Prevalence in people aged 15–19 years was also high (28% [95% CI 24–32] for any HPV; 20% [17–23] for HR-HPV; and 3% [2–4] for HPV-16). HPV-16 age-specific prevalence curves for HR-HPV in Eastern and South-Eastern Asia and Europe and Northern America reflect upward prevalence from ages 15 years to 20 years followed by stable prevalence in older age groups, whereas in Latin America and the Caribbean and Sub-Saharan Africa, the curves appear to trend downwards after they peak.

The pooled prevalence for any HPV was highest in Sub-Saharan Africa (37%, 95% CI 26–49), followed by Europe and Northern America (36%, 32–41). The lowest prevalence was in Eastern and South-Eastern Asia (15%, 95% CI 11–21) and was the only regional prevalence estimate that was significantly different from the others. The same pattern is true for HR-HPV; for all ten of the studies from Eastern and South-Eastern Asia, the prevalence of HR-HPV was 10% (95% CI 7–13), below the global pooled HR-HPV prevalence (21%, 18–24).

Figure 3 Age-specific prevalence of genital HPV infection in men

Global and regional pooled estimates provide us with mean baseline values for HPV prevalence in general populations of men. The study draws attention to the high prevalence, ranging from 20% to 30% for HR-HPV in men across most regions, and the need for strengthening HPV prevention within overall STI control efforts. It also emphasizes the scarcity of HPV data among men from some parts of the world and the importance of expanding HPV prevalence surveys in these areas to inform and measure the effects of prevention efforts. Incorporating HPV vaccination for adolescent males into national immunization schedules can be further considered as vaccine supplies allow and single-dose strategies are assessed.

Reference:

Bruni L, Albero G, Rowley J, et al. Global and regional estimates of genital human papillomavirus prevalence among men: a systematic review and meta-analysis[J]. The Lancet Global Health, 2023, 11(9): e1345-e1362.