High rates of partner change, UAI and STI are factors that facilitate onward transmission during PHI. More active identification of individuals during PHI, the management of STI and highly active antiretroviral therapy may all be useful methods to break transmission networks.

Onward transmission of HIV among MSM is significantly associated with recent infection, sexually transmitted diseases and higher viral load, and reduced by effective HAART. The majority of new infections appear to occur from individuals whose infection was undiagnosed at the time of transmission.

Primary infection with drug-resistant HIV-1 is well documented. We have followed up patients infected with such viruses to determine the stability of resistance-associated mutations. Fourteen patients who experienced primary infection with genotypic evidence of resistance were followed for up to 3 years. Drug resistance-associated mutations persisted over time in most patients studied. In particular, M41L, T69N, K103N, and T215 variants within reverse transcriptase (RT) and multidrug resistance demonstrated little reversion to wild-type virus. By contrast, Y181C and K219Q in RT, occurring alone, disappeared within 25 and 9 months, respectively. Multidrug resistance in 2 patients was found to be stable for up to 18 months, the maximum period studied. We conclude that certain resistance-associated mutations are highly stable and these data support the recommendation that all new HIV diagnoses in areas where primary resistance may occur should undergo genotyping irrespective of whether the date of seroconversion is known.

Objective: To investigate the extent to which primary HIV infection (PHI) presents to healthcare providers and the degree to which it is unrecognised. Methods: All individuals diagnosed with having recent HIV infection between 2003 and 2005 were identified (based on the following criteria: an evolving antibody response, negative HIV test within 18 months or a serological testing algorithm for recent HIV seroconversion). Symptoms of PHI and previous presentation to other healthcare providers were ascertained from HIV clinic notes and laboratory records (a single laboratory performing all of the HIV tests in the area). Results: Of the 108 subjects, 103 (95%) were male and 93 (86%) were men who had sex with men.

Adjunctive use of STARHS with clinical data identified a high and increasing proportion of new HIV diagnoses as recent infections, confirming significant ongoing transmission. Since 2002, 50% of new diagnoses among MSM were recent infections. Identification of additional recent infections by STARHS enables effective intervention that may benefit the individual and reduce onward transmission.