High HPV Immunization Rates Achieved With PATH Initiative

05-09-2012 10:39

August 30, 2012 (Montreal, Quebec) — Exceptionally high immunization rates against human papillomavirus (HPV) have been achieved in target-aged girls in India, Peru, Uganda, and Vietnam as a result of a PATH initiative, researchers told delegates here at the Union for International Cancer Control World Cancer Congress 2012.

Vivien Tsu, PhD, MPH, director of the HPV vaccines project at PATH, reported that a minimum of 80% — and in some countries well over 90% — of school-aged girls received at least 1 dose of the HPV vaccine in the 4 countries to which the initiative has been directed over the past several years.

"The reason the program was successful in these countries, and likely many others, is that there is visible government endorsement and involvement in the program," Dr. Tsu explained. "For the most part, people trust that the government is trying to help them, so if the government is saying 'this is worth doing,' the community participates."

As Dr. Tsu noted, cervical cancer — at least 70% of which is caused by HPV types 16 and 18 — is a major health issue for women in low- and middle-income countries, with a projected incidence in 2030 of more than 750,000 women. In North America and Europe, cytology has been extremely effective in detecting cervical cancer and, more important, precursor lesions.

However, in low- and middle-income countries, "cytology has failed to have much of an impact," Dr. Tsu explained, because these countries lack the necessary resources to offer widespread cervical cancer screening.

Fortunately, the 2 currently available HPV vaccines (Gardasil and Cervarix) have been shown to safely and effectively protect against HPV 16 and 18, she added.

Importantly, both vaccines have also been prequalified by the World Health Organization (WHO), which is necessary for their widespread uptake. Based on WHO recommendations, girls 9 to 13 years of age are the main target group for HPV vaccination.

In an effort to demonstrate that target-aged girls can be successfully vaccinated, PATH directors rolled out 3 vaccine delivery strategies: a school-based HPV program, a community health HPV-based program, and an extension of an already existing outreach program to members of the community.

The process of "parental consent varied from country to country," Dr. Tsu noted. In general, the Ministry of Health in each country dealt with the vaccine as they do any other vaccine. "Parents either signed an authorization allowing their daughters to be vaccinated or, if they did not want their child to be vaccinated, the child could simply say no, and they weren't vaccinated," she explained.

The initiative relied on a pulsed media campaign; the heavy use of radio spots during the weeks prior to immunization helped concentrate publicity.

In total, more than 66,000 young girls were eligible for the HPV program. As Dr. Tsu noted, 97% of the target age group in Vietnam received at least 1 dose of the vaccine and 96% received all 3 doses.

In India, 88% of the target group received at least 1 dose and 79% received all 3 doses. Immunization rates were also very high in Uganda, with more than 96% of eligible girls receiving 1 dose and 89% receiving all 3 doses. In Peru, more than 80% of eligible girls received all 3 doses.

"There was little difference in the coverage between strategies," Dr. Tsu observed. "We saw that with strong community mobilization efforts and training of healthcare workers, the program can be successful."

Dr. Tsu noted that healthcare workers who delivered the vaccine and teachers in schools where the HPV vaccine program was administered need to be trained to answer questions about the vaccine. "If the administrators don't know the answers to [questions that are raised], they can't inspire the confidence that is needed to make the program successful."

A crisis communication plan also needs to be put into place to deal with any rumors that arise related to the vaccine and to dispel their potentially negative influence quickly.

Session chair Silvana Luciani, from the Pan American Health Organization, pointed out that the vaccines are "an important part of cervical cancer prevention."

"What PATH is doing on some of its demonstration projects is really yielding critical information on the implementation of these vaccines and showing us that it is feasible, that you can attain high coverage rates. It's one thing to have the vaccine, the actual implementation is quite another," Luciani added.

Union for International Cancer Control (UICC) World Cancer Congress 2012. Presented August 28, 2012.


Fonte: https://www.medscape.com