Syphilis and HIV Co-infection in New Mexico, 1998-2007

Background:
Since 2000, primary and secondary (PS) syphilis cases have increased in the U.S., predominantly among men who have sex with men (MSM), a group at high risk for HIV infection. Studies have shown syphilis facilitates HIV transmission and increases in early syphilis cases may indicate increased HIV transmission.

Objective:
Describe PS and Early Latent (PS&EL) syphilis cases in New Mexico (NM) who are coinfected with HIV.

Method:
PS&EL syphilis cases reported from January 1998 through June 2007 were reviewed and cross-matched with the NM HIV/AIDS registry to identify coinfected cases.

Result:
Of 832 reported PS&EL syphilis cases, 72 (8.7%) were coinfected with HIV at the time of their syphilis diagnosis. HIV infection was diagnosed >1 year before syphilis for 43 (59.7%) cases (mean 7.3yrs; range 1.2 – 22yrs). The percentage of coinfected cases by year ranged from 0-17% and, since 2001, 3-year moving averages show a steady increase from 2.3%-12.1%. Two of the six coinfected females were injection drug users (IDU); three had sex with HIV infected male partners. Of 66 coinfected males, 48 (72.7%) were MSM with no other risk factor identified; seven (10.6%) were MSM/IDU; and two heterosexual men reported sex with prostitutes. For 10 cases no risk factors were identified. Forty (55.6%) coinfected cases were diagnosed with P&S syphilis and 32 with EL syphilis: seven (9.7%) were also concurrently diagnosed with neurosyphilis.

Conclusion:
HIV coinfection among PS&EL syphilis cases in NM is increasing. Additional prevention efforts need to be made to change sexual behaviors to prevent the spread of syphilis and HIV.

Implications:
Syphilis/HIV coinfections have important implications for patient care (e.g., neurological evaluation and more frequent laboratory testing after syphilis treatment) and partner counseling. Public health programs should cross-match syphilis and HIV/AIDS registries and provide comprehensive partner counseling and referral services for all syphilis cases.