Syphilis, a sexually transmitted venereal disease, is rising among gay and bisexual men after being nearly eliminated in the United States more than a decade ago, according to a federal study.
The increase in syphilis among gay men is a major public health concern, said researchers at the Centres for Disease Control and Prevention, because it indicates sexual behaviour that could lead to an increase in HIV transmission.
The US syphilis rate in 2013 was 5.3 cases per 100 000 people, more than twice the all-time low of 2.1 cases per 100 000 people in 2000, the CDC reported. The majority of patients with the disease, which is treatable, were men who had sex with other men.
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Strategies that proved effective in lowering heterosexual syphilis rates have not worked as well among gay and bisexual men, said Gail Bolan, director of the CDC's Division of STD Prevention.
"We've got to re-evaluate and look at new approaches that we can use to drive these rates down," she said.
Cases nearly doubled
Syphilis is rarely fatal but can lead to health problems such as blindness and stroke, Bolan said.
From 2005 to 2013, the number of US syphilis cases reported nearly doubled, from 8 724 to 16 663, the CDC said.
In 2013, men accounted for about 91% of all reported cases. The highest rates of syphilis were among black men, although the largest increases were reported among Hispanic and white men, the CDC said.
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Among women, the syphilis rate decreased from 1.5 cases per 100 000 people in 2008 to 0.9 cases per 100 000 people in 2013, largely because of a decline in the number of black women with the disease, the study said.
The federal health agency recommended a prevention effort that includes increased screening for the disease and stresses the importance of using latex condoms, limiting sex partners and encouraging monogamous relationships with partners who do not have a sexually transmitted disease.
Syphilis up among gays and bisexuals
Syphilis infections alarmingly high