Most people infected with HIV do not know that they have become infected, because they do not feel ill immediately after infection. However, some people at the time of seroconversion develop “Acute retroviral syndrome” which is a glandular fever-like illness with fever, rash, joint pains and enlarged lymph nodes.
Seroconversion refers to the development of antibodies to HIV and usually takes place between 1 and 6 weeks after HIV infection has happened.
Whether or not HIV infection causes initial symptoms, an HIV-infected person is highly infectious during this initial period and can transmit the virus to another person. The only way to determine whether HIV is present in a person's body is by testing for HIV antibodies or for HIV itself.
After HIV has caused progressive deterioration of the immune system, increased susceptibility to infections may lead to symptoms.
HIV is staged on the basis of certain signs, symptoms, infections, and cancers grouped by the World Health Organization (WHO).
Interim WHO clinical staging of HIV/AIDS and HIV/AIDS case definitions for surveillance (2005): http://www.who.int/hiv/pub/guidelines/clinicalstaging.pdf
- Primary HIV infection - may be asymptomatic or experienced as Acute retroviral syndrome
- Clinical stage 1 - asymptomatic or generalized swelling of the lymph nodes
- Clinical stage 2 - includes minor weight loss, minor mucocutaneous manifestations, and recurrent upper respiratory tract infections
- Clinical stage 3 - includes unexplained chronic diarrhoea, unexplained persistent fever, oral candidiasis or leukoplakia, severe bacterial infections, pulmonary tuberculosis, and acute necrotizing inflammation in the mouth. Some persons with clinical stage 3 have AIDS.
- Clinical stage 4 - includes 22 opportunistic infections or cancers related to HIV. All persons with clinical stage 4 have AIDS.
Most of these conditions are opportunistic infections that can be treated easily in healthy people.