Boys are more likely to receive the quadrivalent human papillomavirus vaccine (HPV4) if their mothers receive flu shots or Pap screenings, according to a Kaiser Permanente study published in the American Journal of Public Health.

The study examined the of more than 250,000 aged 9 to 17 years enrolled in the Kaiser Permanente Southern California health plan and found that a total of 4,055 boys – or 1.6 percent of the membership in this age group – initiated the HPV4 vaccine between October 2009 and December 2010. Researchers found that the HPV4 vaccination rate was 16 percent higher in boys whose mothers had received a within the previous year than in boys whose mothers did not. In addition, the vaccination rate was 13 percent higher in boys whose mothers had a Pap screening in the last three years than boys whose mothers did not have a Pap test.

The study also found that boys whose mothers had a history of were 47 percent more likely to receive the HPV4 vaccine although the researchers note that this association did not reach statistical significance. In addition, HPV4 vaccine uptake was found to be higher among boys who were Hispanic, resided in neighborhoods with lower levels of income and , and enrolled in a Medicaid program.

"Our study findings suggest that a mother's receipt of preventive services may have an impact on their son's HPV4 vaccination," said Rulin Hechter, MD, PhD, study lead author and researcher with the Kaiser Permanente Southern California Department of Research & Evaluation. "These mothers might be more familiar with preventive measures for HPV infection, influencing their decision to have their children vaccinated."

According to the Centers for Disease Control and Prevention, HPV is a common virus that is easily spread by skin-to-skin contact and is considered to be the main cause of cervical cancer in women with about 12,000 new cases each year in the United States. The CDC considers the HPV vaccine a safe and effective way to protect females and males against some of the most common types of HPV and the health problems the virus can cause.

In October 2009, the CDC's Advisory Committee on Immunization Practices, or ACIP, issued a permissive use recommendation for the HPV4 vaccine, which meant that the vaccine was recommended for boys aged 9 to 26 to reduce the likelihood of acquiring genital warts but it was not included in the routine childhood vaccine schedule for boys. In these instances, parents often played a deciding role as to whether their sons would receive the vaccine. However in late 2010, the CDC approved the new vaccine indication for anal cancer. In 2011, the ACIP issued a routine use recommendation of HPV4 vaccination in males aged 11 to 12 years. Under a routine use recommendation, physicians are more likely to promote the vaccine. The researchers are collecting additional data following the introduction of indication for anal cancer and routine use recommendation to further understand the impact of the changes in recommendation on uptake of this vaccine among boys.

"Given that vaccination offers an opportunity to achieve community immunity and reduce transmission of HPV, understanding a mother's health-seeking behaviors may help health care professionals develop strategies for increasing vaccination rates among adolescent boys," Hechter said.

Kaiser Permanente can conduct transformational health research in part because it has the largest private patient-centered electronic health system in the world. The organization's record system, Kaiser Permanente HealthConnect®, securely connects 9.1 million patients to 1,700 physicians in 611 medical offices and 37 hospitals. It also connects Kaiser Permanente's research scientists to one of the most extensive collections of longitudinal medical data available, facilitating studies and important medical discoveries that shape the future of health and care delivery for patients and the medical community.

Journal information: American Journal of Public Health

Provided by Kaiser Permanente