TB/HIV: a clinical manual - libdoc.who.int - World Health Organization

infections have occurred in East Africa, Europe, Asia and Latin America.Both types cause AIDS and the routes of transmission are the same.However, HIV-2 transmission is slightly less easy and the progression ofHIV-2 infection to AIDS may be slower.1.2.2 HIV/AIDS epidemiologyBy the end of 2002, there were an estimated 42 million adults andchildren living with HIV or AIDS. Of these, 28.5 million (68%) were livingin sub-Saharan Africa, and 6 million (14%) in South and South-East Asia.In 2002, an estimated 5 million adults and children became infected withHIV, and an estimated 3.1 million adults and children died fromHIV/AIDS. 2.4 million (77%) of these deaths occurred in sub-SaharanAfrica. Sub-Saharan Africa is the region with the highest overall HIVseroprevalence rate in the general adult (15–49 years) population (9% asof end 2002).Of 25 countries with an adult HIV seroprevalence rate above 5% in 2001,24 are in sub-Saharan Africa. The only other country with an adult HIVseroprevalence greater than 5% is Haiti. In 9 countries (all in SouthernAfrica), the adult HIV seroprevalence rate is 15% or above. Sub-SaharanAfrica thus bears the largest burden of the HIV/AIDS epidemic. However,certain countries in other regions are also badly affected by HIV, with anadult HIV seroprevalence of 1–5%, e.g. Cambodia, Myanmar and Thailand(South-East Asia) and Belize, Guatemala, Guyana, Haiti, Honduras, Panama,and Suriname (the Americas). HIV seroprevalence appears to be stabilizingin sub-Saharan Africa but is still increasing in some other large populations,e.g. in the Russian Federation.1.2.3 HIV transmissionWorldwide the most common route of HIV transmission is throughsexual intercourse. Other sexually transmitted infections (especiallythose that cause genital ulcers) increase the risk of HIV transmission.The main routes of HIV transmission vary between regions. The mainroutes of transmission of HIV in sub-Saharan Africa are through sexualintercourse, blood and from mother to infant. In most low-incomecountries roughly equal numbers of men and women are HIV-infected.Bloodborne HIV transmission occurs through contaminated bloodtransfusion, injections with contaminated needles and syringes, and theuse of non-sterile skin-piercing instruments. The commonest route ofHIV transmission in the fast-growing HIV epidemics in the RussianFederation and Ukraine is through injecting drug use.28 BACKGROUND INFORMATION ON TB AND HIV