A single HPV shot protects against cancer-causing virus, major study finds

A single HPV shot protects against cancer-causing virus, major study finds

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A single shot may be enough to provide highly effective protection against the human papillomavirus (HPV) and its long-term cancer risks, new clinical research from Africa has found. The study found that a single dose of the vaccine was about 90% or more effective at preventing infection with several types of cancer-causing HPV until 18 months later. The findings support the adoption of a single-shot strategy for HPV prevention, say the authors and other experts, which could substantially scale up the vaccine worldwide.

In 2006, the U.S. Accepted The world’s first HPV vaccine: Gardasil, which was developed by Merck & Co. A few years later, it would approve GlaxoSmithKline’s Cervarix. These first-generation vaccines provide protection against both HPV types 16 and 18, which are believed to account for about 70% of cervical cancer cases, as well as other HPV-associated cancers, such as the penis, are found in the rectum and. Neck. The later approved version of the Gardasil vaccine protects against nine types — including two types that don’t cause cancer but do cause most genital warts. Currently, the nine types of Gardasil vaccine are the only vaccines used in the US (Cervarix was taken off the market in 2016 due to low popularity). HPV is primarily spread through sex, and it doesn’t take a long time for young people to contract HPV, which means that vaccination is most effective when given before people become sexually active.

It is clear by now that HPV vaccines are prevent Many cases of cervical and other cancers in the future. A 2019 study predicts that vaccination, combined with Pap smear screening, may effectively erase it Cervical cancer in the US within the next 20 years. This initial success has come despite a relatively low vaccination rate, with only 50% of American teen boys and girls. earning Full schedule of his shots. Rates are even lower in poorer areas of the world, where the majority of cervical cancer cases occur. Worldwide, only 15% of eligible girls vaccine Against HPV, and Cervical Cancer Has sustained Being the fourth most common cause of cancer in women globally, more than 300,000 women died in 2020.

HPV vaccines were originally approved as a three-dose course for all eligible people. But evidence has shown that two doses provide as much protection as three doses when given quickly, and it is currently recommended Children in the US and elsewhere who start vaccination before the age of 15 only need two doses. Some studies have suggested that even a single dose should provide comparable protection, and research is ongoing to test that theory. The results of one such large trial—the Ken Xi study conducted in Kenya, Africa—are finally published Today in NEJM Evidence Journal.

The trial involved 2,275 sexually active women aged 15 to 20, who were randomized into three groups. One group received a single dose of two types of HPV vaccine, then later a meningitis vaccine; The second group received nine types of vaccine and then the meningitis vaccine, and the last group received the meningitis vaccine before the delayed HPV vaccine shot. This last group served as a kind of control, as the risk of contracting HPV would probably be higher in the period before the vaccine was received than in the other groups.

The study found that vaccines two and nine were estimated to be 97.5% effective at preventing HPV types 16 and 18. The nine types of vaccine overall were found to be 89% effective at preventing all seven high-risk HPV types included in the shot. This protective effect was observed until 18 months later, when the study ended. As found in other studies, the vaccines were also safe, with no serious adverse events associated with them.

“Single-dose HPV vaccination may facilitate rapid scale-up of vaccination worldwide to meet the goal of cervical cancer eradication,” the authors wrote.

A single HPV shot protects against cancer-causing virus, major study finds

The findings are already set to change how some countries approach cervical cancer prevention. Earlier today, the World Health Organization’s Strategic Advisory Group of Experts on Immunization announced its conclusions of a review on data for a single-dose strategy. They now say that the country follows a one- or two-dose schedule for girls aged 9–14 (the WHO’s primary target for vaccination), as well as a one- or two-dose for young women aged 15 to 20. Schedule can be adopted. Those over 21 are still advised to take at least two doses spaced six months apart.

“I firmly believe that the end of cervical cancer is possible. The Cervical Cancer Eradication Initiative was launched in 2020 to address many challenges, including inequality in vaccine access. Princess Nothemba (Nono) Assistant Director General for Families, Women, Children This single-dose recommendation has the potential to rapidly take us to our goal of vaccinating 90% of girls by the age of 15 by 2030, said Simeela, and adolescents at the WHO, a. Statement.

It is not known whether countries such as the US will necessarily follow WHO’s lead, although outside experts do see you from time to time Recommending changes to the vaccination schedule. Follow-up research will also be needed to track how long protection from a single dose of HPV vaccine may last, although the authors point to the data Suggestion That it is at least more than a decade.