Question

Can my girlfriend's CD4 count tell her when she became HIV positive?

16 September 2011. Related: All topics, CD4 and viral load.

My girlfriend in Kenya has a CD4 count of 1540.

Can this give her a clue as to when she contracted HIV and the extent of the disease progression?

Her doctor doesn’t have the facilities to measure viral load.

Answer

Answer: Simon Collins

Hi

There are no tests to accurately find out how long someone has been HIV-positive.

Guessing this from someone’s CD4 count is very difficult. This is because there is such a wide range of responses to infection. Some people progress very quickly and some people so slowly that HIV seems to cause very little impact on their CD4 count.

The best estimate is usually from a history of possible risks, and then perhaps if heavy flu-like symptoms occurred within a week or two of one of those exposures.

A ‘detuned’ HIV test called STARHS or RITA is someone used to estimate whether infection is likely to have occurred within the last six months or so. However, this test is mainly used for population studies and does not have high accuracy for individual results.

Your girlfriend has a very strong CD4 count, at the high end of normal. Approximately 95% of HIV-negative people have a CD4 count within the range 400-1600. This means that whenever she caught HIV, the virus has not caused serious damage.

A target CD4 count for someone starting treatment, is to increase their CD$ count to over 500. As your girlfriend’s CD4 count is already well above this, there would not be a reason to use treatment, unless there were other factors.