Vaccinating both boys and girls reduces transmission across the entire population.
In September 2022, Brazil quietly redrew the boundaries of who deserves protection from cancer, extending HPV vaccination to all children aged 9 to 14 regardless of sex — a recognition that preventable disease does not discriminate. The move responds to years of incomplete coverage and a growing understanding that shielding only girls from a virus that harms everyone was always an incomplete strategy. With an estimated 10 million Brazilians already infected and 700,000 new cases arising each year, the expansion is less a breakthrough than a long-overdue correction in the country's relationship with prevention.
- Brazil's HPV vaccination rates have stalled well below the 80% national target — São Paulo recorded only 57.67% coverage among boys and 68.41% among girls in the prior year, leaving millions of children exposed to a virus that causes multiple cancers.
- The virus is far more than a cervical cancer threat: HPV drives over 90% of anal cancers, 63% of penile cancers, and significant shares of throat, vulva, and vaginal cancers, making the gap in male vaccination a quiet public health crisis.
- Starting September 19, 2022, boys as young as 9 became eligible for the first time, with health officials betting that reaching children earlier — before sexual debut, when antibody response is strongest — will finally push coverage past the threshold that matters.
- The two-dose public schedule is already in place, the clinics are open, and the science is settled: 98% protection against the four most dangerous HPV subtypes awaits any child who walks through the door — the remaining question is whether families will.
In mid-September 2022, Brazil's federal government expanded its HPV vaccination program to cover all children aged 9 to 14, regardless of sex. By September 19, clinics in São Paulo were already administering the shot to boys as young as 9 — something that had never been possible under the previous policy, which restricted male eligibility to ages 11 through 14.
The human papillomavirus spreads through sexual contact and direct skin-to-skin transmission, and its consequences extend far beyond cervical cancer. HPV is responsible for nearly all cases of cervical cancer, more than 90 percent of anal cancers, and 63 percent of penile cancers, along with significant shares of throat, vulva, and vaginal cancers. Brazil's Health Ministry estimates at least 10 million people in the country are currently infected, with 700,000 new cases each year. Vaccinating children before adolescence — before the immune system has encountered the virus — produces a stronger antibody response, which is why the timing of this intervention matters so much.
The expansion was driven in part by persistently low coverage. In São Paulo, only 57.67 percent of boys and 68.41 percent of girls had been vaccinated the previous year, both figures falling short of the 80 percent national target. By lowering the eligible age for boys, health officials hoped to reach more children earlier and lift overall rates across the country.
Through the public system, the vaccine is given in two doses six months apart. The Brazilian Society of Immunization recommends three doses for fuller protection, and that three-dose schedule remains standard for immunocompromised patients — including those living with HIV, organ transplant recipients, and cancer patients up to age 26 — all of whom receive it free of charge.
What the expansion ultimately signals is a shift in how Brazil frames HPV prevention. For years, the vaccine was treated largely as a women's health issue. Extending it equally to boys acknowledges that HPV-related cancers threaten people of all sexes, and that reducing transmission requires protecting everyone. Whether vaccination rates will climb to meet the 80 percent goal remains uncertain, but the infrastructure is now in place for every child in Brazil between 9 and 14 to receive protection against cancers that, with sustained effort, need not happen at all.
In mid-September 2022, Brazil's federal government made a quiet but significant shift in how it protects children from cancer. The HPV vaccine, which had been available to girls aged 9 to 14 and boys aged 11 to 14, suddenly became available to all children between 9 and 14 regardless of sex. By Monday, September 19, the vaccine was already being administered in São Paulo, marking the first time boys as young as 9 could receive protection against the human papillomavirus.
The vaccine has been part of Brazil's public health system since 2014, introduced gradually as a preventive measure against diseases caused by HPV. The virus spreads through sexual contact or direct contact with infected skin and mucous membranes, and it is responsible for nearly all cases of cervical cancer, more than 90 percent of anal cancers, and 63 percent of penile cancers. It also causes a significant share of throat, vulva, and vaginal cancers, along with genital warts. The strategy of vaccinating before adolescence, before sexual activity begins, makes biological sense: the immune system produces more neutralizing antibodies when the body has not yet encountered the virus.
Brazil's decision to expand the program came against a backdrop of incomplete coverage. In São Paulo the previous year, only 57.67 percent of boys aged 11 to 14 had been vaccinated, and 68.41 percent of girls aged 9 to 14. Both figures fell short of the 80 percent target set by the National Immunization Program. By lowering the age for boys to 9, health officials hoped to reach more children before they became sexually active and to boost overall vaccination rates across the state and nation.
The vaccine itself is administered in two doses through the public system, with six months between the first and second injection. The Brazilian Society of Immunization recommends three doses—at 9 years old, then two months later, then six months after the first—but the National Immunization Program bases its two-dose schedule on studies showing effectiveness with the reduced regimen. For people living with HIV, organ transplant recipients, and cancer patients between 9 and 26, the vaccine remains available free of charge with a three-dose schedule.
The scale of HPV infection in Brazil underscores why this expansion matters. The Health Ministry estimates that at least 10 million Brazilians are infected with the virus, with 700,000 new cases emerging each year. Globally, roughly 105 million people carry HPV types 16 or 18, the strains most likely to cause cancer. A gynecological oncologist at Hospital Leforte in São Paulo emphasized that vaccinating both boys and girls is essential not only to prevent transmission but to reduce the future burden of disease. Cervical cancer ranks as the second most common gynecological cancer in Brazil, behind only breast cancer.
The vaccine's safety profile is strong. Side effects are minimal—mild fever and soreness at the injection site are the most common complaints. For children who complete the full vaccination schedule, protection reaches 98 percent against the four HPV subtypes covered by the quadrivalent vaccine. Even adults who missed vaccination in childhood have begun seeking the shot; some people in their late twenties and thirties who tested positive for HPV have reported lower viral levels after vaccination, though these doses are typically obtained through private clinics rather than the public system.
What makes this expansion significant is not just the policy change itself but what it signals about how Brazil understands cancer prevention. For years, HPV vaccination was framed primarily as a women's health issue. The expansion acknowledges that boys face real risk from HPV-related cancers of the penis, anus, and throat, and that vaccinating them protects not only their own health but also reduces transmission in the broader population. Whether vaccination rates will actually climb to the 80 percent target remains to be seen, but the infrastructure is now in place for any child in Brazil between 9 and 14 to walk into a health clinic and receive protection against a virus that causes preventable cancers.
Notable Quotes
The vaccine should be applied as early as possible to produce more antibodies that will protect against cancers that could occur in the future.— Melissa Palmieri, epidemiological surveillance physician, São Paulo Health Department
The virus is not only associated with cervical cancer. For boys, the risk is imminent due to penile, anal, throat cancers and genital warts caused by HPV.— Lorena de Castro Diniz, coordinator of the Scientific Department of Immunization at the Brazilian Association of Allergy and Immunology
The Hearth Conversation Another angle on the story
Why did Brazil wait until 2022 to include boys aged 9 to 10? The vaccine has been around since 2014.
The vaccine was introduced gradually, and for years it was framed as a cervical cancer prevention tool—a women's health issue. Boys were added later, starting at 11, but there was no urgency to lower that age. The expansion in 2022 reflects a shift in thinking: recognizing that boys face real cancer risk from HPV too.
What changed in September 2022 specifically?
The government looked at vaccination coverage rates and saw they were stuck below 80 percent. They realized that by expanding eligibility to younger boys, they could reach more children before sexual debut, when the immune response is strongest. It's a practical move to improve coverage.
Is the two-dose schedule in the public system actually enough?
The National Immunization Program says yes, based on effectiveness studies. But the Brazilian Society of Immunization still recommends three doses. There's a gap between what the public system offers and what some experts prefer, though both approaches work.
How many Brazilians actually have HPV right now?
The Health Ministry estimates 10 million infected people, with 700,000 new cases each year. That's a massive reservoir of infection. Vaccinating children now is about preventing those numbers from growing.
Can adults who missed vaccination as children still get protected?
Yes, but it's complicated. Some doctors are prescribing it to adults in their twenties and thirties, especially those who test positive for HPV. The viral levels drop in some cases. But these doses come from private clinics, not the public system.
What's the real barrier to reaching 80 percent coverage?
It's not safety or access—the vaccine is safe and free. It's likely awareness and competing priorities. São Paulo had 68 percent coverage for girls and 58 percent for boys before the expansion. Getting to 80 percent means reaching families who don't prioritize it or don't know it exists.