Category: New treatments

New ways of getting treatment to sexual partners of patients infected with chamydia or gonorrhoea

Treating a sexually transmitted infection in a person is incomplete without treating te sexual partner and thus closing the loop. Current forms of partner notification (PN) are not particularly successful with less than one half of sexual partners attending sexual health (genitourinary medicine) clinics.

A recent study by Claudia Escourt and her colleagues has looked at the feasibility of two different approaches to PN. One was to set up a hotine for the partner to phone a health care worker in the sexual health clinic and after appropriate consultation to collect their treatments either at the sexual health clinic and the secone was for the partner go to a a designated pharmacy and obtain treatment from a trained pharmacist. The partners were also asked to provide urine for chlamydia testing and to attend the sexual health clinic at a time of their own convenience for syphilis and HIV testing.

The preliminary results were encouraging and showed that both systems were acceptable to clients and increased uptake of treatment from 36% to 59% in the case of the clinic hotline and 66% in case of pharmacy.

The only drawback of either strategy was that almost none of the partners accessed HIV or syphilis testing at a later date.

Antiretroviral prophylaxis: a defining moment in HIV control

According to an editorial by Salim Abdool Karim in the Lancet  a defining moment in the global AIDS response has been reached. The discourse is no longer about HIV prevention or HIV treatment; it is now about HIV control through the implementation of antiretroviral treatments as key components of combination interventions.

Barely a year ago, visions of HIV control would have been considered far-fetched. The impetus for this change in mindset, which has been building since the XVIII International AIDS Conference in Vienna last year, emanates from the compelling evidence that antiretroviral drugs prevent HIV infection in the general heterosexual population, which is released this week and presented at the 6th International AIDS Society Conference on HIV Pathogenesis, Treatment and Prevention in Rome by the Partners PrEP and Botswana TDF2 trials.

The Partners PrEP trial, involving 4758 HIV discordant couples from Kenya and Uganda, found that daily oral tenofovir disoproxil fumarate (TDF) and TDF-emtricitabine reduced HIV transmission by 62% and 73%, respectively. The Bostwana TDF2 trial, in 1200 heterosexual men and women from the general population, found that daily oral TDF-emtricitabine reduced HIV transmission by 63%.

Both these are of a similar order of magnitude to that seen with male circumcision and is probably caused by a significant reduction of HIV in the genital tract.

see fig 1 for comparison between different prevension strategies

Several issues were raised by the authors that need further research. There is now no doubt that antiretroviral drugs prevent HIV infection. However, important scientific questions remain. Does the inclusion of emtricitabine in pre-exposure prophylaxis (PrEP) formulations provide sufficient additional benefit to warrant the additional costs and side-effects? Are levels of effectiveness and safety similar for daily use and use-with-sex of PrEP? Do the safety, effectiveness, cost, and acceptability profiles of oral and topical PrEP merit implementation of both formulations? Does PrEP lead to masking of HIV acquisition that is then revealed once PrEP is withdrawn?

UK NHS finally accepts to use quadrivalent HPV vaccine in girls

From next September girls in the United Kingdom being vaccinated against human papillomavirus (HPV) will receive Gardasil, the vaccine that protects against genital warts as well as cervical cancer.

The Joint Committee on Vaccination and Immunisation recommended that the HPV vaccine should be offered routinely to girls aged 12 to 13 years and in a catch-up programme to those up to 18 years of age. Since then, 1.5 million young women and girls have been protected.

GlaxoSmithKline, which has been providing the Cervarix vaccine to the UK’s HPV vaccination programme since it launched in September 2008, said in a statement that it did not take part in the latest tendering exercise to provide a vaccine for the programme because the government made it clear that it wanted to protect girls against the types of HPV that caused cervical cancer and those that caused genital warts.

Gardasil, which is supplied by Sanofi Pasteur MSD, protects against HPV types 16 and 18, which cause 70% of cervical cancers, and HPV 6 and 11, which are responsible for nine in 10 cases of genital warts. Cervarix protects against HPV types 16 and 18.

When the UK programme launched, health campaigners criticised the choice of Cervarix as being short sighted and a missed opportunity (BMJ 2008;336:a451, doi:10.1136/bmj.a451)

Worldwide Gardasil has been the vaccine of choice. It has been selected by health authorities in the United States, Australia, New Zealand, Canada, Switzerland, Italy, Spain, and Sweden for regional or national vaccination programmes against cervical cancer.

Research from Australia has shown that cases of genital warts have nearly disappeared since 2007 when the national vaccination programme against cervical cancer using Gardasil was introduced (Sexually Transmitted Infectionsdoi:10.1136/sextrans-2011-050234). The study found that new diagnoses of genital warts among women under 21 years attending a sexual health centre in Melbourne fell from 18.6% in 2007-8 to 1.9% in 2010-11 and in heterosexual men aged under 21 from 22.9% to 2.9%. During the period before the introduction of the vaccination programme, new cases of genital warts rose by 1.8%.

Use of human papillomavirus (HPV) vaccine causes dramatic fall in genital warts

An important new study by a team of researchers working in a sexual health clinic in Melbourne, Australia has shown that 4 years after a government funded program of vaccinating girls and women aged 12-18 there was a dramatic decline in new cases of genital warts in heterosexual women and also of men with a new diagnosis of genital warts. Cases of genital warts attending the Melbourne Sexual Health Centre fell from 18.6% of all new diagnosis in women under 21 in 2007-2008  to 1.9% in 2010-2011. Interestingly there was a similar dramatic fall in new cases of genital warts in men under 21 over the same time period from 22.9% to 2.9%. The odds ratio per year for diagnosis of genital warts that was adjusted for number of sexual partners from July 2007 until June 2011 in women <21 years was 0.44 (95% CI 0.32 to 0.58) and in heterosexual men aged <21 was 0.42 (95% CI 0.31 to 0.60)  – a fall of over 55% in both sexes.

There was no drop in the incidence of new genital warts diagnosis in women aged over 30 or in men who have sex with men adding weight to the authors’ conclusions that the fall in new wart cases in younger men and women was a consequence of vaccination. It is argued that a reduction in new infections in young women had resulted in a reduced pool of infection and hence also caused a similar drop in their male sexual partners.

The Australian government was providing the vaccine free to all girls and women aged 12-18 from 2007 until the end of 2009. Since then free vaccine has been only offered girls aged 12-13.  The vaccine used in Australia contains antigens from HPV 6 and 11 which are the commonest HPV genotypes associated with genital warts as well as HPV 16 and 18 associated with cervical cancer.

Unfortunately the quadrivalent vaccine is not the one chosen for use by the Department of Health in the UK. A recent study which we reported earlier showed that the quadrivalent vaccine is more cost effective than the bivalent vaccine currently recommended for use in the UK.

 

Syphilis resistance to macrolide antibiotic increasing in London

Resistance to the second line treatment regimen for syphilis reported from a large London sexual health clinic is causing concern. Macrolide antibiotics are used as second line treatment for early syphilis which is caused by a bacterium Treponema pallidum, in patients allergic to penicillin. Fortunately penicillin resistance has never been reported in syphilis and penicillin remains an effective treatment against this disease worldwide. The problem arises in patients with penicillin allergy who for some reason (eg pregnancy) cannot be treated with tetracyclines, the best alternative therapy.