Background

Men who have sex with men (MSM) are at risk for cancers attributable to human papillomavirus (HPV), including oropharyngeal cancer. Human papillomavirus vaccination is recommended for US MSM through age 26 years. Oral HPV infection is associated with oropharyngeal cancer. We determined oral HPV prevalence and risk factors among young MSM.

Methods

The Young Men's HPV study enrolled MSM aged 18 through 26 years from clinics in Chicago and Los Angeles during 2012 to 2014. Participants self-reported demographics, sexual behaviors, vaccination and human immunodeficiency virus (HIV) status. Self-collected oral rinse specimens were tested for HPV DNA (37 types) by L1-consensus PCR. We calculated adjusted prevalence ratios (aPR) and 95% confidence intervals (CI) for risk factors associated with oral HPV among participants not previously vaccinated.

Results

Oral HPV was detected in 87 (9.4%) of 922; 9-valent vaccine types were detected in 37 (4.0%) of 922. Among HIV-positive participants, 17 (19.3%) of 88 had oral HPV detected. Oral HPV was more prevalent among those reporting first sex at 18 years of age or younger (aPR, 2.44; 95% CI, 1.16-5.12); HIV infection (aPR, 1.99; 95% CI, 1.14-3.48); greater than 5 sex partners within the past month (aPR, 1.93; 95% CI, 1.13-3.31); performing oral sex on greater than 5 partners within the last 3 months (aPR, 1.87; 95% CI, 1.12-3.13); and having greater than 5 male sex partners within the last 3 months (aPR, 1.76; 95% CI, 1.08-2.87). Only 454 (49.2%) of 922 were aware that HPV can cause oropharyngeal cancers.

Conclusions

Many oral HPV infections were with types targeted by vaccination. Oral HPV infections were significantly associated with HIV and sexual behaviors. Fewer than half of participants were aware that HPV could cause oropharyngeal cancer.

Haemophilus influenzae (Hi) can cause meningitis and other serious invasive disease. Encapsulated Hi is classified into six serotypes (a-f) based on chemical composition of the polysaccharide capsule; unencapsulated strains are termed nontypeable Hi (NTHi). Hi serotype b (Hib) was the most common cause of bacterial meningitis in children in the pre-Hib vaccine era, and secondary transmission of Hi among children (e.g., to household contacts and in child care facilities) (1,2) led to the Advisory Committee on Immunization Practices (ACIP) recommendation for antibiotic chemoprophylaxis to prevent Hib disease in certain circumstances.* High Hib vaccination coverage since the 1990s has substantially reduced Hib disease, and other serotypes now account for most Hi-associated invasive disease in the United States (3). Nevertheless, CDC does not currently recommend chemoprophylaxis for contacts of persons with invasive disease caused by serotypes other than Hib and by NTHi (non-b Hi). Given this changing epidemiology, U.S. surveillance data were reviewed to investigate secondary cases of invasive disease caused by Hi. The estimated prevalence of secondary transmission was 0.32% among persons with encapsulated Hi disease (≤60 days of one another) and 0.12% among persons with NTHi disease (≤14 days of one another). Isolates from all Hi case pairs were genetically closely related, and all patients with potential secondary infection had underlying medical conditions. These results strongly suggest that secondary transmission of non-b Hi occurs. Expansion of Hi chemoprophylaxis recommendations might be warranted to control invasive Hi disease in certain populations in the United States, but further analysis is needed to evaluate the potential benefits against the risks, such as increased antibiotic use.

BACKGROUND: Nontypeable Haemophilus influenzae (NTHi) is the most common cause of invasive H. influenzae disease in the United States (US). We evaluated the epidemiology of invasive NTHi disease in the US, including among pregnant women, infants, and people with human immunodeficiency virus (PWH). METHODS: We used data from population- and laboratory-based surveillance for invasive H. influenzae disease conducted in 10 sites to estimate national incidence of NTHi, and to describe epidemiology in women of childbearing age, infants aged ≤30 days (neonates), and PWH living in the surveillance catchment areas. H. influenzae isolates were sent to the Centers for Disease Control and Prevention for species confirmation, serotyping, and whole genome sequencing of select isolates. RESULTS: During 2008-⁠2019, average annual NTHi incidence in the US was 1.3/100 000 population overall, 5.8/100 000 among children aged <1 year, and 10.2/100 000 among adults aged ≥80 years. Among 225 reported neonates with NTHi, 92% had a positive culture within the first week of life and 72% were preterm. NTHi risk was 23 times higher among preterm compared to term neonates, and 5.6 times higher in pregnant/postpartum compared to nonpregnant women. More than half of pregnant women with invasive NTHi had loss of pregnancy postinfection. Incidence among PWH aged ≥13 years was 9.5 cases per 100 000, compared to 1.1 cases per 100 000 for non-PWH (rate ratio, 8.3 [95% confidence interval, 7.1-9.7]; P < .0001). CONCLUSIONS: NTHi causes substantial invasive disease, especially among older adults, pregnant/postpartum women, and neonates. Enhanced surveillance and evaluation of targeted interventions to prevent perinatal NTHi infections may be warranted.