HIV Weekly - 6th February 2013

HIV epidemic in UK gay men

Rates of new HIV infections among gay men in the UK changed little between 2001 and 2010, new research has shown.

Gay men are one of the groups most affected by HIV in the UK. Researchers calculated that each year between approximately 2100 and 2200 gay men were newly infected with HIV.

The rate of new infections remained steady despite increased uptake of HIV testing and expanded use of antiretroviral therapy. There’s a lot of excitement about the use of HIV treatment as prevention and there’s evidence from other countries that it can have an impact on rates of new infections in gay men.

But the researchers think that the proportion of UK gay men who are diagnosed and are on treatment with an undetectable viral load is still too low for treatment to have a major impact on the epidemic.

UK guidelines recommend that people should start HIV treatment when their CD4 cell count is around 350. However, earlier treatment is recommended for people with HIV-negative partners.

It’s important to emphasise that condoms provide a very high level of protection against HIV and other sexually transmitted infections (STIs). Untreated STIs in either partner can increase the risk of HIV transmission.

For more information on transmission and prevention of HIV and other STIs, our HIV & sex booklet is available at www.aidsmap.com/booklets.

Tuberculosis – vaccine

Tuberculosis (TB) is the single most significant cause of serious illness and death in people with HIV. Even in a relatively rich country like the UK, TB is one of the most common AIDS-defining illnesses.

Prevention of TB is a global health priority. For HIV-negative people there is a live vaccine against TB known as the BCG vaccine, although its effectiveness appears to vary in different populations. It should not be given to people with HIV, because there is a small chance that it might cause a TB-like illness.

BCG isn’t 100% effective. Researchers are therefore trying to find a new, more effective vaccine or a way of boosting the effectiveness of BCG.

MVA85A is an experimental vaccine that boosts BCG. Results of laboratory studies have been promising and researchers wanted to see if it was safe and effective in HIV-negative infants who had already received the BCG vaccine.

Approximately 2800 South African infants were randomised to receive MVA85A or a placebo.

The experimental vaccine was found to be safe and provoked an immune response.

However, it didn’t reduce the risk of developing TB disease or infection with a mild form of TB.

Nevertheless, the researchers were encouraged by their findings, which they believe show that real progress is being made in the quest for a more effective TB vaccine.

They recommend further studies to see if the vaccine is effective in adults and people with HIV.

The authors write, “MVA85A could potentially protect adolescents and adults against pulmonary tuberculosis, in view of the fact that immunologically immature infants do not respond as well to this vaccine as adults do”.

For more information on HIV & tuberculosis, you may find our HIV & TB booklet useful. All the booklets in this series are available at www.aidsmap.com/booklets.

Drug-resistant tuberculosis

TB can be cured with treatment consisting of a combination of antibiotics.

However, there is a growing international problem with drug-resistant TB.

Especially concerning is the emergence of strains of so-called XDR-TB (extensively drug-resistant TB). XDR-TB is resistant to important first- and second-line drugs. It is very difficult to cure and is associated with a high mortality rate.

Outbreaks of XDR-TB have been seen around the world and many have involved people with HIV.

One of the first outbreaks was at the Tugela Ferry Hospital in South Africa between 2005 and 2006. It involved over 500 people, and almost all were living with HIV.

Researchers wanted to see how the infection was spread.

Care at the hospital is provided in large wards. Beds are close together and there is no special ventilation.

The researchers found that XDR-TB was being spread from patient to patient in the hospital.

TB expert Dr NR Gandhi believes that important lessons can be learnt from the outbreak: “Patients with highly drug-resistant forms of TB must quickly receive their diagnosis, start an effective regimen…and [be] managed in settings where they are less likely to expose susceptible individuals until they initiate an effective treatment regime.”

HATIP, our newsletter for people working in resource-limited settings, recently published an edition for nurses about drug-resistant tuberculosis (TB). It summarises key recommendations on the diagnosis and treatment of drug-resistant TB, and highlights examples of best practice in the care of people with drug-resistant TB. There is an archive of HATIP online at www.aidsmap.com/hatip.

HIV and hepatitis C – monitoring

Spanish researchers have found that a simple test that monitors liver stiffness is an accurate way of predicting the risk of liver disease and death in people co-infected with HIV and hepatitis C.

Many people living with HIV also have hepatitis C. Liver disease caused by hepatitis C is a leading cause of serious illness and death in people with this co-infection.

Hepatitis C damages the liver, causing fibrosis (hardening) and cirrhosis (permanent scarring). The traditional test used to assess the extent of fibrosis and cirrhosis is a liver biopsy.

However, this test is uncomfortable and can involve a risk of complications.

The health of the liver can also be assessed using a non-invasive test called FibroScan. This involves placing a probe close to the liver which sends out painless pulses that can assess the stiffness of the liver.

Spanish researchers have found that liver stiffness is an accurate predictor of liver-related complications and death. Their research involved over 500 people who were monitored for an average of 71 months.

“Baseline liver stiffness is the strongest predictor of liver-related complications and of all-cause mortality in HIV/HCV-coinfected patients on antiretroviral therapy,” conclude the authors.

Their study also showed the benefits of treating hepatitis C. The risk of liver disease and death was much lower for people who underwent successful treatment.

For more information on HIV & hepatitis, you may find our HIV & hepatitis booklet useful. All the booklets in this series are available at www.aidsmap.com/booklets.