/ 20 June 2013

HIV, ARVs and the cervical cancer vaccine

How SA women will benefit from an HPV vaccine, which the government will introduce next year, will strongly depend on the virus's link with HIV.

Information is emerging on the links between HIV and the human papilloma virus (HPV), which causes cervical cancer, said Helen Rees from Wits University’s Institute of Reproductive Health said at the 6th National Aids Conference held in Durban this week.

The health department will provide 9 and 10-year-old girls in the poorest schools with the vaccine from February next year.

Rees said that every year 6 000 women get cervical cancer and more than 50% die. Many of these women are HIV infected.

“HPV is an extremely common virus: it’s one of the earliest infections that women who are sexually active acquire,” she said.

For most women these infections “spontaneously” clear. However, if this does not happen it leads to pre-cancerous lesions and then develops to cervical cancer over a long period of time, sometimes decades.

“That long period has been significantly reduced by HIV positivity – we are seeing younger and younger HIV infected women with late stage cervical cancer.”  

ARVs slow progress of HPV
According to Rees studies of HIV-infected women in Johannesburg hospitals from the late 1990s, before the roll out of HIV drugs or antiretrovirals (ARVs), show a significantly higher risk of developing cervical cancer.

“Later studies show that ARVs can slow the progression of the HPV disease because they restore the immune system. But we don’t think that’s going to get us over this problem completely. We think we’re going to continue to have an excess burden of cervical cancer in HIV infected individuals which is why we need to introduce this vaccine,” explained Rees.

Two vaccines, Gardasil – manufactured by Merck, and Cervarix – produced GlaxoSmithKline are currently on the market and it is still unclear which one will be used in South Africa. The government is in the process of negotiating for affordable prices – in the private sector the vaccines respectively cost R896 and R596 per dose and three are needed per person.

In addition to protecting against cervical cancer, Gardasil also protects against another sexually transmitted infection (STI) – genital warts.

According to research conducted in STI clinics in Gauteng the amount of genital wart cases in males and females has been increasing steadily from the year 2000.

“Not only are we seeing more infected patients, the severity of the disease is greater – and that is largely because of HIV,” she said. 

Improving women's health
The Gavi Alliance, a public-private partnership that provides free immunisations to developing countries for an initial five years, has recently negotiated significantly lower prices for the vaccine and has begun introducing it into poor countries.

On their website they describe the widespread roll out of this vaccine as “the beginning of a dramatic shift in women’s health”.

Although it is a positive sign that South Africa will soon get the vaccine, there are many questions which haven’t been answered – particularly about HIV.

“If we give this vaccine to young women who later become HIV infected, will it still be effective in protecting them from the HPV disease? Will it in fact wipe out the effectiveness of the vaccine? There is no answer to this yet,” she said.