New UK HIV infection data

Jun 1 2004

In the first three months of 2004, 1389 new diagnoses of HIV infection were reported.  This brought the cumulative total to 62,709 since surveillance began in 1982.  To date, 20,307 individuals have been diagnosed with AIDS, of which 12,898 (64%) have died with a further 2818 individuals having died without being reported with AIDS.

Table 1 New diagnoses of HIV in the UK by infection route, sex and year of diagnosis: data to the end of March 2004

Of the 5864 diagnoses reported so far in 2003, 28% (1641) were acquired through sex between men, and 57% (3371) through sex between men and women, with almost two thirds (2199) of those being female (table 1).  Diagnoses among injecting drug users remained relatively low in 2003, making up 2% of the total, reported to date.  Follow-up to ascertain the probable route of infection was still ongoing for 10% (602) of reports. 

Since 1999, the number of infections diagnosed in heterosexual men and women have exceeded those in men who have sex with men (MSM).  Diagnoses in both groups has subsequently risen each year .  The increase in diagnoses has been substantial in those infected through heterosexual sex, with the majority of these infections acquired abroad.  For diagnoses in heterosexual men and women made in 2003, 70% were infected in African countries, and 7.5% in other parts of the world (table 2).  Although these figures include individuals infected while travelling or living abroad, for the most part they represent those who were born in and who lived for most of their lives in the country where they were infected. 

Table 2 New diagnoses of HIV in those infected through sex between men and women by year of diagnosis: data to the end of March 2004

Infections transmitted through blood transfusion or from mother to child are for the most part acquired outside the United Kingdom (UK).  Men who have sex with men are the group most at risk of acquiring HIV in the UK.  For new diagnoses in 2003 in MSM, where country of infection was reported (891 of 1641), 84% (749) were infected in the UK. This compares with 11% (328/2966) of heterosexual cases – this figure includes those who had a “high risk” partner and who were infected in the UK, and excludes from the denominator 405 individuals where country of infection was not yet ascertained.  Numbers of individuals infected through heterosexual contact in the UK have been increasing gradually and continue to make up around 10% to 11% of new diagnoses in heterosexual men and women annually.

Table 3 describes new diagnoses of HIV infection over time by the region where the earliest diagnosis was made.  London remains the focus of HIV in the UK, with 2566 (44%) of new diagnoses in 2003 being made there.  A further 21% of diagnoses were in the regions adjacent to London.  All regions have seen increases in new diagnoses each year since 1999 including areas that previously saw relatively few HIV cases, such as the North East, Yorkshire and Humberside, Eastern England, and Wales.  In each of these regions (and Wales) new diagnoses more than doubled between 1999 and 2002.  Figures for 2003 are incomplete due to reporting delay and on the basis of previous patterns of reporting delay they will exceed those for 2002, and are expected to do so by a considerable margin. 

Since 1997 there has been a steadying in the number of AIDS cases and deaths (table 3, figure 1).  There has also been a reduction in AIDS reporting since the advent of HAART (highly active antiretroviral therapy), and AIDS defining illnesses are more likely to be reported if the HIV and AIDS diagnoses are simultaneous.  In 2003, 77% (545) of the 705 AIDS cases diagnosed were diagnosed at the same time as the HIV infection.  Reporting of deaths is also subject to reporting delay so the figure of 462 already known about in 2003 is elevated compared to previous years.  Reports of deaths occurring in HIV infected individuals in 2002 rose from 349 at the end of March 2003 to 405 a year later.

Table 3 New diagnoses of HIV infection by country and region where diagnosed and year of diagnosis: data to the end of March 2004