Lengthier secondary schooling substantially reduces the risk of HIV infection, particularly for girls, according to researchers from Harvard T.H. Chan School of Public Health.

The practice could be a cost-effective way to block the spread of the virus.

For each additional year of secondary school, students lowered their risk of HIV infection by 8 percentage points about a decade later, from 25% to about 17% infected, researchers found in a study in Botswana.

First author Jan-Walter De Neve said:

“These findings confirm what has been fiercely debated for more than two decades—that secondary schooling is an important structural determinant of HIV infection and that this relation is causal.”

Harvard Chan School researchers worked with colleagues at Boston University and in Botswana, where about 22% of adults aged 15-49 were infected with HIV as of 2013, one of the highest HIV infection rates in the world.

The authors were able to conduct a “natural experiment,” thanks to a 1996 school reform measure in Botswana that made it easier and more beneficial for students to complete 10 years of education. The policy change resulted in an average 0.8 additional years of schooling among teens.

By comparing groups of students who entered secondary school in or after 1996 with those in earlier groups, the researchers could estimate the impact of additional secondary education on the risk of HIV infection.

The researchers found additional years of secondary school, defined as grades 8-12, were associated with significantly lower risk of HIV, especially for women, whose HIV risk dropped by 12 percentage points with each added year of secondary school. No effect was found for people with less than nine years of schooling.

Length of secondary schooling and risk of HIV infection in Botswana: evidence from a natural experiment Jan-Walter De Neve, Günther Fink, S V Subramanian, Sikhulile Moyo, and Jacob Bor The Lancet Global Health, online June 28, 2015, DOI: 10.1016/S2214-109X(15)70161-0

Photo: First Baptist Nashville/flickr

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