Question
What does my CD4 percentage mean?
7 January 2017. Related: All topics, CD4 and viral load.
Answer
Most information about how HIV affects your health comes from your CD4 count. This includes how HIV has damaged your immune system and how HIV treatment (ART) is making your immune system stronger.
The CD4 count is usually given as a number (usually between 1 to about 1600 cells/mm3).
This number is called the ‘absolute’ CD4 count.
However, many things affect this absolute number. These includes the time of the day, what you have eaten, if you have taken exercise, or if you have other infections. Each of these factors can affect your CD4 count but they are not related to immune system.
If your CD4 results are ever much higher or much lower than you expect, your doctor should look at your CD4 percentage (CD4%).
The CD4% can indicate whether this is a real change, or just a fluctuation. The CD4% is generally more stable.
The absolute CD4 count is still best at predicting risk of HIV progression.
The CD4% is the percentage of white blood cells that are CD4 cells. In an HIV negative adult the average CD4% is about 45%.(But this can range from 24% – 64%)
In adults, a CD4 percentage of 12-15% is considered similar to a CD4 count of 200 cells/mm3. A percentage of 15-20% is similar to an absolute count of 300 cells/mm3.
Babies and children with HIV are monitored using CD4%, because their absolute CD4 counts are much higher than adult counts, especially in the first few years.
CD4% may be an independent predictor of HIV disease progression, and a low CD4% should be considered as a factor in starting treatment, even when the absolute CD4 count is relatively ok.
This answer was updated in January 2017 from a question first posted on 8 October 2012.
Hi Mike,
The articles that you’re reading are right. When you’re positive and on meds what’s important is getting your viral load below 50. If you’ve been on meds for 3 months then your viral load should be undetectable.
CD4’s can and do fluctuate, this is normal. Please see here for more info: http://i-base.info/qa/115
I just experianced my first drop in CD4 count since diagnosis, 300 to 259 at 16% what worries me is the slow recovery rate. Coupled to a drop in count it makes me worry for long term prognosis. Most articles essentially say don’t worry about it just get the viral level under 50.
Hi Gertrude,
Info about treatment and viral load testing can be found in this guide: http://i-base.info/guides/starting
Please also see the following links: http://i-base.info/ttfa/section-2/8-what-is-a-viral-load-test/
I started my treatment, but I don’t understand how does viral load ,mean,can u please explain, and what must I do to test it,m just using treatment at clinic
Hi Shamsa,
Are you on HIV treatment (ART)? Taking ART can reduce your viral load to such tiny amounts the result comes back as undetectable. Everyone is talking about Undetectable = Untransmittable (U=U). And U=U means that you cannot transmit HIV even if you don’t use condoms.
Please see more U=U info here.
Your CD4 count is a guide to how well your immune system is. So it’s not good or bad. Many people are fit and healthy with a CD4 count of 416. And exercise that suits your fitness and age is good for everyone!
Hi… for example am positive and I have a negative partner!! We’ve been using condom since we started our relationship.. what should I do if we want to have sex without condom without him getting infected??
And also my cd4 counts as 416 is that good or bad??
Also is it okay for me to do exercise??
Hi Jane,
Like Simon said its important that you start treatment. Is this something that you’re considering? Please see here:
http://i-base.info/guides/starting
No I’m not on any treatment as yet.I did a viral load test but I have not received the results.
Hi Jane. In order to talk about your results I need to know if you are currently on treatment.
If not, then these results show that it is important to see a doctor about starting HIV treatment.
If you are on treatment, I need to know you CD4 history and when you started. Also, do you know if you get a viral load test at your clinic>
I have a cd4 count of 234 and a percentage of 10.1. Is it bad?