Testing centers in Valencia report a falling incidence of HIV infection among members of all risk groups with the most precipitous fall among heterosexuals. The highest rate remains among injecting drug users.
The researchers conclude the lower incidence and prevalence over time could be from greater testing or prevention messages. It is widely believed that knowing one’s HIV status is a major contributor to the reduction of the spread of the disease because people who know their status are less likely to expose others.
Spain presents an example of a non-circumcising country with a low and falling incidence and prevalence of heterosexually transmitted HIV/AIDS.
Complete text of the article after the jump.
High HIV prevalence amongst injecting drug users in Valencia
The proportion of individuals undergoing HIV testing in Valencia who
received a positive result fell significantly between 1988 and 2003,
according to an article published in the online edition of Sexually Transmitted Infections.
Declines were seen in all HIV risk categories. Nevertheless, almost a
quarter of all injecting drug users tested HIV-positive, and the
investigators observed an increase in HIV incidence in gay men from
Few data are available on HIV infection trends over time in Spain.
Therefore investigators from the Centre for AIDS Information and
Prevention (CIPS) in Valencia, Spain, undertook a study to determine
trends in HIV testing, serial HIV prevalence and HIV incidence in
Valencia between 1988 and 2003. Their study sample included all 21,241
individuals who had an HIV test at a CIPS clinic in Valencia.
A little over two-thirds of the individuals attending for an HIV test
were men, 27% were injecting drug users, 43% were heterosexuals, and
13% were gay men.
Between 1988 and 1990, injecting drug users accounted for the majority
(57%) of clinic attendees, but this fell to 14% of total attendances by
1997 – 2003. At the same time as attendances by injecting drug users
fell, there was an increase in the number of heterosexuals requesting
an HIV test, and by 1997 – 2003, a total of 56% of all individuals
undergoing HIV testing were heterosexuals. The proportion of gay men
attending for HIV tests remained stable over the 15 years of analysis.
A total of 3,234 individuals tested HIV-positive, representing an HIV
prevalence of 15% for the entire study period. But HIV prevalence fell
significantly over time. Between 1988 and 1990, prevalence was 35%, but
there was a year-on-year fall thereafter, and by 1999 prevalence had
fallen to 10%, and it fell to 3% by 2003.
Despite this overall fall, HIV prevalence amongst injecting drug users remained high: 26% in 2003.
The highest HIV prevalence observed in gay men was 25% in 1990. This
was followed by a steady decline, and by 2003 the HIV prevalence
amongst gay men had fallen to 6%.
Prevalence amongst heterosexuals peaked at 11% in 1988 and 1991, but by 2003 had fallen to 2%.
Repeated HIV tests were performed on 4,424 individuals and 340 of these were positive.
HIV incidence peaked in 1988 at 6%, and then fell dramatically in all
HIV risk groups before peaking again at 8% in 1995. The 1995 peak was
followed by another overall fall in incidence for all risk groups, but
the investigators noted with concern a significant increase in HIV
incidence amongst gay men from 2001 onwards.
The investigators attribute decreased HIV prevalence amongst drug users
to prevention efforts such as methadone maintenance therapy and needle
Although the investigators describe the apparent increase in HIV
incidence amongst gay men as “worrying”, they suggest that this
statistic should be treated with caution and write that it could
“reflect either ineffective HIV prevention messages…or the use of HIV
Other countries in western Europe have experienced an increase in
heterosexual HIV prevalence due to migration from high prevalence
countries. Such increases are not supported by the data from Valencia
which show decreases in both heterosexual prevalence and incidence.
Hurtado I et al. Trends in HIV testing, serial HIV prevalence
and HIV incidence among people attending a Center for AIDS Prevention
from 1988 – 2003: increases in recent years in HIV incidence in men who
have sex with men. Sexually Transmitted Infections (online edition), 2006.