Author: Mohsen Shahmanesh

Need and acceptability of human papillomavirus (HPV) vaccination in men

HPV vaccination of young women with the quadrivalent vaccine (HPV4) resulted in a dramatic fall in genital warts and cervical cancer rates. However rolling out a similar vaccination in young men has been hampered by arguments that  male HPV4 vaccination programmes exceed cost-effectiveness thresholds.

Unlike the USA and Australia, European countries do not include men in HPV vaccination programmes, instead focusing on achieving expanded coverage among women to promote herd immunity.

Yet there is  evidence that HPV4 vaccination offers substantial clinical benefits to men and is cost effective among men who have sex with men (MSM). MSM have largely been excluded from mathematical models. A recent study in the journal Sexually Transmitted Infections has shown that HPV related conditions such as anal/genital warts and rectal infections are likely to be profoundly underdiagnosed among MSM in most European cities. The paper concluded that there is an urgent need to improve sexual healthcare tailored to MSM at risk for STIs.

There is also the argument  for a gender-neutral (universal) approach to vaccination.

In the same issue of STI a meta-analysis shows that there are currently a number of obstacles to acceptability of HPV vaccination in  men. They concluded that Public health campaigns should aim to promote positive HPV vaccine attitudes and awareness about HPV risk in men. The paper recommended interventions to promote HPV vaccination for boys and to overcome  obstacles to HPV vaccine acceptability for men.

Bacterial vaginosis (BV): a common cause of vaginal discharge in need of more research

Bacterial vaginosis (BV) is a common condition in women presenting as a malodorous vaginal discharge. The  smell is often worse after sex and arround the menstrual period. Occasionally there is an associated  itching or burning sensation although most women with BV only have the discharge. BV can also be detected in women who are totally symptom free.

BV is caused by an imbalance of the normal vagina flora and its mechanism remain poorly understood. An updated review by the Centre for Disease Control (CDC), USA confirms a commonly observation that BV follows sexual intercourse with a new partner and multiple partners as well as vaginal douching.

BV, itself an benign though troublesome nuisance is associated with increased risk of a number of infections or conditions:

  • Having BV can increase a woman’s susceptibility to HIV infection if she is exposed to the HIV virus.

  • Having BV increases the chances that an HIV-infected woman can pass HIV to her sex partner.

  • Having BV has been associated with an increase in the development of an infection following surgical procedures such as a hysterectomy or an abortion.

  • Having BV while pregnant may put a woman at increased risk for some complications of pregnancy, such as preterm delivery.

  • BV can increase a woman’s susceptibility to other STDs, such as herpes simplex virus (HSV),chlamydia, and gonorrhea.

  • The bacteria that cause BV can sometimes infect the uterus (womb) and fallopian tubes (tubes that carry eggs from the ovaries to the uterus). This type of infection is called pelvic inflammatory disease (PID).
  • Pregnant women with BV more often have babies who are born premature or with low birth weight (low birth weight is less than 5.5 pounds). Pregnant women who have had previous premature of low birth weight babies should be tested and treated for BV in third trimester regardless of symptoms.

Trichomonas vaginalis – a neglected STI with major global health implications

Trichomonas vaginalis (TV) is the most prevalent curable sexually transmitted infection (STI) globally. Yet at least 80% of TV infections are asymptomatic, though even asymptomatic infections are a public health concern.

In addition to the risk of transmission to sex partners, TV infection has been associated with as much as a 2.7-fold increase in the risk of HIV acquisition, a 1.3-fold increase in the risk of preterm labour, and a 4.7-fold increase in the risk of pelvic inflammatory disease.

A recent review in the journal Sexually Transmitted Infections (STI) highlights the current knowledge of the global epidemiology of TV infection. These include sex differences in the incidence and prevalence of infection, and the potentially important role of female sex hormones, and the menstrual cycle in mediating TV susceptibility and natural history.

WHO has estimated that over half the 248 million new TV infections each year occur in men. By contrast, 89% of prevalent TV cases are found among women. Biological differences between the sexes contribute to these striking differences between men and women.

There has also been an increased understanding of the mechanisms underlying resistance to metronidazole – the current sole drug available to eradicate the organism.

Recent innovations in detection, including the availability of nucleic acid amplification tests (NAATs), have improved our understanding of the natural history of TV infections. These innovations and our increased understanding of this common sexually transmitted infection should help us combat the global epidemic in TV.

Human papillomavirus may increase acquisition of HIV

Many sexually transmitted infections (STI) such as herpes and other ulcerative STI’s, chlamydia and gonorrhoea have been known to be associated with increased acquisition of HIV.

A recent meta-analysis in the journal Sexually Transmitted Infections suggests that human papillomavirus (HPV) infections, which is associated with genital warts as well as a number of malignancies, may also be associated with sexual transmission of HIV.

Since HPV is the commonest sexually acquired STI, this association, if confirmed, will have important public health consequences. This is particularly true as most sexually acquired HPV infections can be prevented by  vaccinating children.

 

HPV and HIV acquisition
HPV and HIV acquisition

 

 

HPV vaccination has real population effect on genital warts in Australia

A recent editorial by Simon Barton and Colm O’Mahony in the BMJ highlight real and large declines at the population level of genital warts in both sexes in areas where mass vaccination by the quadrivalent vaccine have been implemented. The authors summarise the achievements to date:

1. A study published by Hammad Ali et al in the same issue reports that survey of of 85 770 new patients from six Australian sexual health clinics show a remarkable reduction in the proportion of women under 21 years of age presenting with genital warts—from 11.5% in 2007 to 0.85% in 2011 (P<0.001). Only 13 cases of genital warts were diagnosed in women under the age of 21 across all six health clinics in 2011. There was no observable effect in women over 30.

2. Interestingly, even though only young women were offered vaccination, there was also a significant decline in genital warts in young men. Between 2007 and 2011 there was a decline of 82% in the prevalence of warts presenting to sexual health clinics in heterosexual men under 21 and 51% in heterosexual men aged 21-30. There were no observed change in prevalence of genital warts in men who have sex with men (MSM). This decline of genital warts in young heterosexual men was thought to be caused to increased herd immunity.

3. Based on these and similar findings and also on grounds of equity the Australian government has begun a publicly funded HPV vaccination program for young men. This aims to reduce the prevalence of genital warts in MSM and also hopefully effect the rising rates of oropharyngeal cancers in men. Ali et al commented that “the vaccination program is expected to increase herd immunity and provide further indirect protection to unvaccinated women” hopefully leading to control, if not elimination of teh targeted HPV types.

4. It is believed that  similar falls in HPV-16 and HPV-18 related cancers – such as cervical, anal and oripharyngeal cancers will be reported in the next few years.

5. The editorial expressed the hope that future vaccines will include other potentially harmful HPV types, such as types 31 and 45.

 

What is in the May issue of STI

The latest issue of STI (Sexually Transmitted Infections) contains articles on increasing resistance of bacterial STI’s, a successful  educational interventions in South London to encourage HIV testing and data supporting the willingness by a substantial section of men who have sex with men to use pre-exposure prophylaxis for HIV.

particularly worrying is the emergence of a novel strategy by the gonococcus to avoid detection by the now widely used DNA amplification methods.

Non-disclosure of known HIV status in patients visiting a sexually health clinic

Currently in the UK it is estimated that 24%, approximately 22 200 individuals, are unaware of their HIV infection . These data are derived from statistical modelling of many  surveillance, and survey-based data sources. One of the surveillance programmes used is the unlinked anonymous HIV seroprevalence survey, the GUMAnon Survey, where patients who have blood taken at a sexually health clinic would in addition give an additional sample which is tested for HIV after the sample is completely anonymised. The limited information accompanying the sample includes whether the person is known to be HIV positive, has a test in the clinic or refuses an HIV test.

A recent study published in the journal Sexually Transmitted Infections (STI) attempted to identify HIV-infected individuals who attend a genitourinary clinics in the UK aware of their HIV status but fail to tell the clinic they are infected, or on treatment.  In this study in addition to anonymised HIV testing the positive samples had viral load (VL) estimation and after excluding known HIV positives the remaining the samples were analysed for the presence of a panel of antiretroviral drugs.

The authors identified 130 individuals attending a single London sexually transmitted infection clinic in 2009 who refused an HIV test.  Of 28 patients identified by the anonymised test  as being HIV positive who had not admitted to being infected 10 patients underwent a test at the clinic and received a positive test.

The other 18 had  refused an HIV test, although found to be positive by the anonymised test. Thirteen of these (72%, 95% CI: 47% to 90%) had a blood viral load (VL) below detection level  (n=11) or VL <1000 copies/ml (n=2) suggesting they were on antiretroviral treatment. Eight had sufficient blood to undergo antiretroviral testing, and all were positive for the presence of drug; all with therapeutic levels of clinically appropriate combinations.

Thus nearly three quarters of HIV positive patients (72%) who refused an HIV test, and hence would have been considered as not knowing their HIV status, were indeed aware of their status and are on treatment.

These results “presents a number of challenges and dilemmas both for clinics and surveillance systems” says Jackie Cassell, editor of STI journal, who went on to also points out the difficult issues of confidentiality in sexual health services in the age of electronic health records.

Use a condom for Valentine Day

HIV/TB care association has launched a Twiter-Facebook campaign in Cape Town to encourage condom use. Under slogan is Love=Condom and with Valentine Day as a prop, the campaign aims to address the rising rates of HIV – especially.

In the UK the relentless rise in HIV in men who have sex with men to record levels in 2012 has also raised concern that the safe sex message is not getting through. The Healthe Protection Agency which provides annual report on rates of HIV and other sexually transmitted infections has made a number of recommendations for controlling the HIV epidemic.

  • Implementing safer sex programmes promoting condom use and HIV testing are a priority, particular for higher risk groups, including men who have sex with men and black African communities.
  • In areas with high HIV prevalence (prevalence greater than 2 per 1,000 people aged between 15 and 59 years old), routine HIV testing should be performed for all general medical admissions and people registering at GP practices. GPs should offer and recommend HIV testing.
  • HIV testing should be offered to people with tuberculosis and people with HIV should be screened for tuberculosis.
  • The benefits of treatment with antiretroviral drug treatments should be discussed with all people receiving HIV care.
  • HIV care needs to be continually monitored to ensure it continues to be of high quality.

Maybe we should take a leaf out of the South African TB/HIV Care Association.

Self-taking vaginal sample best test for chlamydia and gonorrhoea in women

The optimal diagnostic sample for Chlamydia trachomatis detection should detect the maximum number of infected people.  In women without symptoms the sample of choice is a self taken vulvovaginal swab, which can be done in the privacy of one’s home. But it is not clear whether a vulvovaginal swab or an endocervical swab is the optimum sample in women with symptoms requiring speculum examination.

A recent study by Sarah Shoeman and colleagues published in the BMJ compared the two sampling methods. They showed that in women attending a sexual health centre vulvovaginal swabs were significantly better at detecting chlamydia infection than endocervical swabs among women with symptoms of a sexually transmitted infection.

In these cases, using endocervical samples rather than vulvovaginal swabs would have missed 9% of infections, or 1 in 11 cases of chlamydia infection

A  parallel  study by the same group showed that self taken vaginal swabs tested by the  Nucleic acid amplification tests (NAATs) which offer increased sensitivity for detecting gonorrhoea, is significantly more sensitive and offers good specificity for detecting gonorrhoea compared with standard gonorrhoea culture methods.

However  confirmation of positive results with a second NAAT is essential in low prevalence populations such as the UK, to avoid false positive results

Women and clinicians can be confident that self taken vulvovaginal swabs are as accurate as clinician performed tests for the detection of chlamydia and gonorrhoea in women without symptoms and should be the test method of choice in asymptomatic women.