WHO case definition for AIDS surveillance

Case definition for Adults

  • An adult / adolescent (above 12 years of age) is considered to have AIDS if atleast 2 of the major signs and 1 minor sign is present in the person and these signs are not known to be due to a condition unrelated to HIV infection

Major signs:

  • Weight loss of more than 10% of body weight
  • Chronic diarrhoea of more than 1 month duration
  • Prolonged fever of more than 1 month duration (intermittent or constant)

Minor signs:

  • persistent cough of more than 1 month duration (not applicable for patients with tuberculosis)
  • oropharyngeal candidiasis
  • generalised pruritic dermatitis
  • history of herpes zoster
  • chronic progressive of disseminated herpes simplex
  • generalised lymphadenopathy
  • This definition is specific in that most of the patients diagnosed to have AIDS by the clinical definition will actually have the disease
  • But this not very sensitive as nearly half of the patients with severe illness related to HIV are not detected
    • because many AIDS related oppurtunistic infections are not included in this definition

Case definition for Children

  • A child is considered to have AIDS if at least 2 major and 2 minor signs are present and these signs are not known to be due to a condition unrelated to AIDS.

Major signs:

  • Weight loss or abnormally slow growth
  • Chronic diarrhoea of more than 1 month duration
  • Prolonged fever of more than 1 month duration (intermittent or constant)

Minor signs:

  • persistent cough
  • oropharyngeal candidiasis
  • generalised rash
  • generalised lymph node enlargement
  • recurrent common infections (like respiratory infections)
  • confirmed HIV infection in mother
  • The case definition in case of children is not very specific especially in the areas where childhood malnutrition and tuberculosis are common