The National Institutes of Health has spent millions of dollars studying male sex workers in Peru, including more than $400,000 to determine why gay men get syphilis in the South American country.

"Syphilis remains an uncontrolled infectious disease globally, with high prevalence and incidence in certain high risk populations, affecting more than 20 percent of men who have sex with men (MSM) in Peru," according to the grant, awarded by the National Institutes of Health (NIH).

"The incidence of syphilis in MSM in Peru is about 9 cases per 100 person-years," it said. "We are proposing a study to improve our understanding of syphilis epidemiology and molecular biology, particularly among MSM."

The study will "recruit a cohort of MSM and transgender persons at high risk for syphilis," to measure incidence rates of syphilis over a two year period. Researchers will look at molecular and immunological factors for why MSM get syphilis and create a system for diagnosing and managing the sexually transmitted disease.

The project, "Syphilis: Translating Technology to Understand a Neglected Epidemic," has received $464,272 since 2012.

The funding has gone to researchers at Universidad Peruana Cayetano Heredia, a private university in Lima, Peru. The school has two other active studies from the NIH devoted to male sex workers.

A $160,920 study is sending "motivational messages" via "mobile-phone text messaging, email, or instant messaging robots" to encourage gay men to get tested for HIV in Peru.

Messages include information on HIV testing, not "stigmatizing and stereotyping messages or images about ‘being gay.’"

Another HIV prevention intervention study by the university is focusing on "MSM/transwomen," at a cost of $146,524.

The University of California, Los Angeles (UCLA) is conducting numerous studies on male sex workers in Peru, as well.

UCLA researchers are examining how community "skills building" can help "Fletes," a term for bisexual male sex workers who engage in survival sex work for very low wages. The project cost $168,197 in 2013.

The university also received $323,360 to give "partner therapy" to Peruvian male sex workers who have gonorrhea or chlamydia for another study beginning in 2011.

Public health interventions ($272,160) and "partner notification strategies" ($754,901) are also being researched by UCLA to reduce HIV and sexually transmitted infections, specifically targeted at Peruvian male sex workers.

In all, the listed studies have cost U.S. taxpayers $2,122,137.