Late HIV diagnosis

Export Indicator

Percentage and number of adults and children newly diagnosed with HIV with an the initial CD4 cell count <200 cells/mm3 and <350 cells/ mm3 during the reporting period
What it measures

People who have not received a timely HIV diagnosis.

Rationale
As countries scale up HIV services, it is important to monitor whether people are diagnosed at an earlier stage and what percentage of the people are still diagnosed at a late stage. Late diagnosis is detrimental to people’s health, and those with low CD4 counts are more likely to transmit the virus.
Numerator
1. Numbers of people living with HIV with an initial CD4 cell count <200 cells/mm3 at the time of diagnosis
 
2. Numbers of people living with HIV with an initial CD4 cell count <350 cells/mm3 at the time of diagnosis
Denominator

Total number of people living with HIV with an initial CD4 cell count during the reporting period

Calculation

Numerator/denominator

Method of measurement
Based on data from laboratory information systems and from the records of people in treatment. Data can be compiled from health services registries, case report forms or laboratory information systems. Individuals with CD4 count results should only be included if the test was conducted within one month of the diagnosis date.
Measurement frequency

Annual

Disaggregation

0–14 years for children and 15 years and older by sex (men and women) for adults.

Explanation of the numerator
People living with HIV whose initial CD4 lymphocyte count was less than 200 cells/mm3 and people living with HIV whose initial CD4 lymphocyte count was less than 350 cells/mm3 in the reporting period. Reporting on the number of people with a CD4 lymphocyte count less than 350 cells/mm3 also should include those with a CD4 lymphocyte count less than 200 cells/mm3.
Explanation of the denominator

Number of people living with HIV who had an initial CD4 lymphocyte count at the time of diagnosis in the reporting period.

Strengths and weaknesses
This indicator may not distinguish between people given a late diagnosis and those who arrived late for care and treatment in a setting where CD4 testing is available. Differentiating them requires knowing the diagnosis date and the date of the initial CD4 lymphocyte count. Dates differing by more than one month may indicate a delay in being linked to care, although it is possible that late diagnosis and late linkage to care may occur in the same person. Previous HIV testing history and clinical records should be reviewed to the extent possible to exclude counting people who were previously diagnosed at some earlier date and are only seeking a second or confirmatory diagnosis later. Finally, this indicator may not include all individuals diagnosed during the reporting period if there are substantial reporting delays in the diagnosis data or CD4 count test result.