Cervical cancer, the fourth most frequent malignancy in women worldwide and affecting 90% of those in low- and middle-income nations, is caused by sexually transmitted HPV in more than 95% of cases.
The Single-Dose HPV Vaccine Evaluation Consortium, led by PATH, has acquired and assessed evidence on the efficacy of a single-dose HPV vaccination schedule from clinical trials, observational studies, and modelling analyses during the previous four years. Results from numerous clinical trials assessing a single dosage of the HPV vaccine are now becoming available.
A single dose of the HPV vaccination is roughly 98 percent effective in preventing persistent HPV infections caused by HPV-16/18, the most prevalent HPV type that causes 70 percent of cervical malignancies, according to a randomised controlled clinical trial conducted in Kenya.
After a single dose, protection against HPV infections is comparable to that provided by two or three doses and lasts for at least 10 years, according to two high-quality observational studies conducted in India and Costa Rica. Another study in Tanzania revealed that by bridging the immunological response to studies carried out in India and Costa Rica, efficacy in young females aged 9 to 14 years can be predicted.
Model-based research, which repeatedly demonstrates that single-dose vaccination, in settings where HPV vaccinations have not yet been introduced, will lead to a significant reduction in cervical cancer cases, supports a single-dose HPV vaccination schedule. More girls receiving a single dose of the vaccine will prevent many more incidences of cervical cancer than fewer girls receiving a second dose.
According to the analysis, a single dosage of the HPV vaccine offers cervical cancer prevention that is equally effective to two dose schedules. Increasing the number of girls who receive the potentially life-saving vaccine could completely shift the game in terms of disease prevention.