Epidemiology

The prevalence of diagnosed HIV amongst black African adults in England is estimated to be 3.7%, which is forty times greater than the prevalence of 0.09% in white adults. Moreover, for every three people who know they have HIV, it is estimated that one other person has it without realising it.¹

Looking at all individuals who accessed HIV care in 2009, over a third (36%, 23,288) were black African people.² Looking at black African people accessing care in more detail:

• Two-thirds (66%) were women or girls.
• Over four-fifths (82%) were in the 25-49 age band. Seven per cent were children or young people, while 11% were aged 50 or over.
• Nine-tenths (91%) acquired HIV through heterosexual sex. The largest other exposure categories were mother-to-child transmission (4.5%) and sex between men (1.4%).
• 42% live in London.

Now turning to people newly diagnosed with HIV in 2009, one third (33%, 2206) were black African people.³ However this is considerably fewer than in 2005, when just under half (48%, 3864) of new diagnoses were in black African people. This may be due to changing migration patterns.

Larger numbers of women than men are diagnosed (63%). This is primarily because of HIV screening at antenatal services and women having more frequent contact with health services generally.

Large numbers of people are diagnosed with HIV ‘late’ (with a CD4 cell count below 350 cells/mm³, at which stage starting treatment is recommended). While the latest report from the Health Protection Agency (HPA) does not break late diagnosis statistics down by ethnicity, it does present specific figures for heterosexual men and women newly diagnosed with HIV (a majority of whom are black African).

In 2009, 66% of men and 59% of women were diagnosed late. Moreover 42% and 35% respectively were diagnosed ‘very late’ (with a CD4 cell count below 200 cells/mm³).⁴

The issue of testing and late diagnosis is covered in more depth in the section Testing and diagnosis.

Nine-tenths of newly diagnosed black African people acquired HIV through heterosexual sex. Nonetheless, around 5% of diagnosed black African men are thought to have acquired their infection through sex with men. (This issue is also covered in more depth in the section Black African men who have sex with men.)

Although a majority of black African people who are diagnosed with HIV in the UK acquired their infection in African countries, the number of black African people acquiring HIV in the UK is increasing. Of all black African people newly diagnosed in 2009 where the location of infection was known (1425), 16% contracted HIV in the UK and 84% were infected abroad. This is a substantial increase in the proportion of infections acquired in the UK from 4% in 1999.³

Moreover, some researchers believe that the HPA’s data on the probable country of infection could underestimate infection in the UK. Some months after diagnosis, 263 black African people were asked to complete a questionnaire that addressed risk behaviour before diagnosis. Medical notes were also consulted for information on symptoms and CD4 cell counts. Based on this, it was estimated that between 25 and 35% of participants had acquired their infection in the UK. Those under the age of 30 when they arrived in the UK and men who have sex with men were more likely to have acquired HIV in the UK.⁵

These findings suggest that prevention activities are needed for black African people in the UK. Moreover these prevention activities need to address sex between men.

Although over a third of black African people (38%) are diagnosed in London, there are significant numbers of diagnoses in most parts of the country. Historically, the capital has had the most accessible and diverse set of HIV services. However, the government’s policy of ‘dispersing’ asylum seekers to other parts of the country has meant that black African people have moved to other towns and cities, where community networks and support services are sometimes lacking.