The global HIV pandemic continues to worsen particularly in African countries with strong links to the UK. At the end of 2003, according to revised UN estimates, over 19 million adults and children with HIV were living in Commonwealth Africa (51% of the global total). The figure is based on individual country estimates released by UNAIDS in July 2004. Significantly, while Black Africans made up 0.8% of the population in the 2001 census, in 2002 they constituted 32% of UK HIV cases.

Since 1999, there have been more diagnoses in heterosexual men and women each year than MSM. Most heterosexual infections diagnosed in the UK were probably acquired in Africa. This accounts consistently for about 75% of new diagnoses in heterosexual men and women each year. Infections acquired in the UK consistently account for about 10% of new diagnoses in each year. As the overall numbers rise, so do the numbers in each of these categories.

Ethnicity information became better reported in 2000 due to a change in surveillance methods. There is a marked difference between the “MSM epidemic” and the “heterosexual epidemic” in the UK. Between 2000 and 2003, the four years, where ethnicity has been reported – over 85% of MSM are white, over 70% of heterosexual men are black African and over 80% of heterosexual women are black African. The proportion of HIV infections diagnosed in the UK among black Africans has increased from 24% (376 of 1598) in 1996 to 58% (3323 of 5732) of all newly reported HIV infections in the UK, for which ethnicity was recorded, in 2003; these continue to be diagnoses of infections that were predominately acquired abroad.

New diagnoses in the UK from an exposure to HIV in Africa show complex trends over time. Early influences from Eastern Africa include many infections from Uganda. More recently infections from South East Africa have become more influential, with infections from Zimbabwe continuing at high levels. Diagnoses of infections acquired in other regions of Africa continue to rise more gradually.

Many heterosexuals are diagnosed late in the course of their infection – particularly men. A CD4 count of 200 is considered to be AIDS defining in the USA. Although this is not part of the UK definition of AIDS a CD4 count of this level is indication of later stage immunosuppression. Heterosexual men are consistently diagnosed at a later stage of infection (around half at a CD4 count of 200 or less) than heterosexual women who in turn are consistently diagnosed at a later stage of infection than men who have sex with men. After the introduction of HAART (highly active antiretroviral therapy), the majority of AIDS cases diagnosed were in those recently diagnosed with HIV in other words, most of those reported with AIDS were diagnosed with HIV late in the course of disease progression. In heterosexual men and women AIDS diagnoses are increasing. (TB plays a large part in these figures)

There are estimated to be around 16,000 Africans living with HIV in the UK – 21% undiagnosed. It is not possible to measure the numbers who are currently living with diagnosed HIV in the UK from the new diagnoses figures. The mobility and age of those most affected and the long duration of HIV infection mean that people may have left the country or may have died and not been reported. Every year a survey to measure the numbers currently living with HIV is carried out (SOPHID = Survey of Prevalent HIV Infections Diagnosed) and gives the best estimate of the current picture. SOPHID figures show that the numbers living with diagnosed HIV in England, Wales and Northern Ireland have more than doubled between 1997 and 2003. Breaking down the numbers from the SOPHID survey by ethnicity. White ethnicities make up the largest numbers of individuals living with HIV (53% of the total in 2003) and black African ethnicities are the second most affected group (35% of the total in 2003) The proportion and numbers of black Africans among the total living with HIV has increased.

In total there were thought to be about 53,000 adults living with HIV at the end of 2003 with 27% unaware of their infection. For African men the estimated total was 6,100 with a third unaware of their infection and for African women, 10,100 with 14% unaware of their infection.