Correctional Services spokesman Manelisi Wolela has denied allegations that student leader Mcebo Dla.
A non-government organisation is calling on all young people to voluntarily get tested for HIV.
Miriam Mhazo, a senior programme manager at New Start, says: "Young people make up more than half of those living with HIV and Aids worldwide.
"It is now more important than ever for them to be informed and involved and to pledge themselves to the cause. The first step in this kind of personal achievement is by knowing your status."
New Start is an HIV counselling centre based in Johannesburg. The organisation also has offices in Bloemfontein, Musina, Durban, Pietermaritzburg, Mthatha, Middledrift, East London, Mafikeng and Cape Town.
Mobile HIV testing facilities take their services to communities.
Mhazo says: "Knowing one's status has vital benefits. If you test positive, you can begin treatment early and will live a longer and healthier life.
"It will also benefit your community to know your status because you can take the necessary precautions to prevent the spread of HIV to others."
She encourages young people to go to any voluntary counselling and testing centre and to discuss HIV and Aids matters with a trained counsellor.
"Pre-test counselling provides individuals with information on HIV and Aids and an assessment of whether a client has been or will be at risk is done. We also draw up a risk-reduction plan, discuss the testing process and possible test results. All of this is confidential.
"The next step is to take the test. We use the 'finger prick' method. No needles are used and it is almost painless.
"After the test, and a short 20-minute wait, the client goes for post-test counselling where the counsellor will give you the result of your test.
"If the results are negative clients are guided on how to remain negative. If the results are positive, the counsellor will counsel the client on living positively. The counsellor will also refer clients for post-test support services, including ARV therapy.
"At no point during the counselling and testing session is a patient asked for his or her name," says Mhazo.
The centres are open from 8am to 6pm from Monday to Friday and from 8am until 2pm on Saturdays.