Patients on PrEP commonly exhibited immunity to hepatitis A virus (HAV) and hepatitis B virus (HBV), but HPV vaccination remains un – common, according to results pub – lished in Sexually Transmitted Infections. Darrell Tan, MD, PhD, and colleagues examined immunity and vaccination against HAV, HBV, and HPV among 633 partici – pants. They identified baseline immunity/vaccina – tion for HAV, HBV and HPV in 69.2%, 81.2%, and 16.8% of PrEP-experienced participants and 58.9%, 70.3%, and 10.4% of PrEP-naïve partic – ipants. Longer PrEP use, frequent sexually trans – mitted and bloodborne infection (STBBI) testing, and HBV immunity were associated with baseline HAV immunity. Characteristics associated with baseline HBV immunity included longer PrEP use and HAV immunity. Age (≤26), annual income, frequent STBBI testing, and HAV immunity were associated with baseline HAV immunity. For those not immune at baseline, overall cumulative proba – bility of immunity/vaccination for HAV, HBV, and HPV was 0.70, 0.60, and 0.53 among PrEPexperienced participants and 0.93, 0.80, and 0.70 among PrEP-naïve participants, respectively.
