Identifying recently acquired HIV infections among newly diagnosed men who have sex with men attending STI clinics in The Netherlands.
OBJECTIVE
The current surveillance system in The Netherlands cannot differentiate recent HIV infections from established infections, which is crucial for estimating the HIV incidence; this information is needed for assessing trends of the HIV epidemic and the impact of prevention interventions. We determined the proportion of recent HIV infections (RI) and estimated HIV incidence using a recent infection testing algorithm (RITA) among men who have sex with men (MSM) newly diagnosed as having HIV attending sexually transmitted infection (STI) clinics.


METHODS
Plasma samples collected between 2009 and 2011 were tested for RI with the Architect HIV Ag/Ab Combo immunoassay. Data on viral load, CD4 count and previous HIV testing were incorporated into the RITA. HIV incidence and 95% CIs were estimated. Logistic regression was used to identify factors associated with RI.


RESULTS
Of the 251 samples tested for RI, 78/251 (31%) infections were determined as recent by the RITA. No significant change over time was observed. The estimated HIV incidence in this high-risk MSM population was 3.3 per 100 person-years (95% CI 2.5 to 4.1). The only factor associated with RI in the multivariable model was being tested for HIV ≥ 3 times in the past (aOR=7.4; 95% CI 2.0 to 27.8).


CONCLUSIONS
The proportion of RIs was comparable to studies in similar settings in Europe. Implementation of the RITA for routine surveillance in The Netherlands to assess trends in RIs over time, to study the infections in other groups and to inform public health actions, is being planned.
Unit of Epidemiology and Surveillance, National Institute for Public Health and Environment (RIVM), Centre for Infectious Disease Control, The Netherlands European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden.
Jussi
J
Sane
Public Health Service of Amsterdam, Amsterdam, The Netherlands.
Titia
T
Heijman
Virus Diagnostic Services, Sanquin Blood Supply, Amsterdam, The Netherlands.
Boris
B
Hogema
Virus Diagnostic Services, Sanquin Blood Supply, Amsterdam, The Netherlands.
Maarten
M
Koot
Public Health Service of Amsterdam, Amsterdam, The Netherlands.
Maaike
M
van Veen
Department of Infectious Disease Control, Public Health Service Rotterdam-Rijnmond, Rotterdam, The Netherlands.
Hannelore
H
Götz
Public Health Service of Amsterdam, Amsterdam, The Netherlands.
Johan
J
Fennema
Unit of Epidemiology and Surveillance, National Institute for Public Health and Environment (RIVM), Centre for Infectious Disease Control, The Netherlands.
Eline
E
Op de Coul
D000328:Adult; D018791:CD4 Lymphocyte Count; D015658:HIV Infections / Q000175:diagnosis* / Q000517:prevention & control / Q000635:transmission; D007722:Health Knowledge, Attitudes, Practice; D018451:Homosexuality, Male; D006801:Humans; D015994:Incidence; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D011159:Population Surveillance; D012725:Sexual Behavior; D013997:Time Factors; D019562:Viral Load
Epidemiology (General); Gay Men; HIV; HIV Testing; Surveillance