Why do people still develop AIDS today?

Even though antiretroviral treatment can prevent the onset of AIDS in a person living with HIV, many people are still diagnosed with AIDS today. There are four main reasons for this:

• In many resource-poor countries antiretroviral treatment is not widely available. Even in wealthier countries, such as America, many individuals are not covered by health insurance and cannot afford treatment.
• Some people who became infected with HIV in the early years of the epidemic before combination therapy was available, have subsequently developed drug resistance and therefore have limited treatment options.
• Many people are never tested for HIV and only become aware they are infected with the virus once they have developed an AIDS related illness. These people are at a higher risk of mortality, as they tend to respond less well to treatment at this stage.
• Sometimes people taking treatment are unable to adhere to, or tolerate the side effects of drugs.