IAS: PEP following sexual assault in Kenya and Thailand - more awareness and follow-up necessary

Not enough is being done to raise awareness of post-exposure prophylaxis as a means of preventing HIV infection after sexual assault in middle-income and resource-limited settings, despite high background levels of sexual violence and HIV infection, two studies from Kenya and Thailand reported on Monday at the 4^th IAS conference in Sydney.

The first, from Kenya, found that while nearly everyone who was eligible for PEP began it, they were much more likely to successfully complete the full course if given relevant counselling. The second, from Thailand, found that PEP was cost-effective. Both concluded that much more needed to be done regarding public – and police – awareness for timely access to PEP.

In Kenya – where 29% of women report having experienced sexual violence in the past year – the standard of care for sexual assault survivors includes treatment for sexually transmitted infections, counselling for HIV testing, and, if HIV-negative, post-exposure prophylaxis (PEP) for HIV (including PEP adherence counselling).

An observational study presented by Nduku Kilonzo, Research Director of Nairobi’s Liverpool VCT and Care, evaluated the delivery and uptake of these services in three district hospitals in Kenya, where local HIV prevalence ranges between 7% and 21%.

Between November 2003 and June 2005, a total of 295 survivors of sexual assault were seen. The majority (89%) were female, and most were very young – the median age was only 16.5 years. More than half (56%) were children; the youngest survivor was just 16 months old, and the oldest was 102.

One in seven (14%) of the survivors did not present to one of the three hospitals within 72 hours of their assault and were, therefore, not eligible for PEP. Ms Kilonzo noted that there was “very little awareness, very little information, very little knowledge about PEP following sexual trauma” in Kenya, and that efforts should be made to increase awareness.

A further 11% of the cohort did not consent to a baseline HIV antibody test, and were not offered PEP. Of those who took an HIV antibody test, 13 (6%) were found to have been HIV-positive prior to the assault, although this increased to 9% of the adult women who were tested. Another 43 individuals (11%) were lost to follow up, and consequently, just 59% of the cohort of 295 individuals began PEP, with 51% of the cohort completing the full course of PEP.

There was one documented seroconversion – in a seven year-old girl – among the members of the cohort who received PEP. Ms Kilonzo speculates that this could be due to “poor adherence within a context of trauma,” and noted that “in resouce-poor settings PEP following sexual violence is not actively followed-up, and we need to be exploring how to improve adherence.”

Although counselling about HIV, HIV antibody testing, and PEP is supposed to be available to all sexual assault survivors, according to national guidelines, only 50% had at least one counselling session, with 40% receiving at least three consecutive sessions. Ms Kilonzo and her colleagues found that individuals who had received at least one counselling session were nearly three times as likely to complete the course of PEP (OR=2.7, p=0.004). Consequently, she concluded that, “HIV PEP counselling for assault survivors is essential and should address other consensual HIV risk.”

During the question and answer session that followed, Ms Kilonzo noted that there were “no data describing the other risk behaviours, the other contextual risks, of survivors of sexual violence” and that this study provided an opportunity to examine further the role of counselling in survivors of sexual assault.

In a similar programme in Bangkok, Thailand, survivors of sexual assault are offered testing for HIV (with a three-month follow-up test) and other STIs, counselling, and PEP if less than 72 hours have elapsed since the assault.

Chanthana Vitavisini, of Police General Hospital in Bangkok, presented data that reviewed PEP for sexual assault provided at the hospital during 2006 – this hospital sees more than half of all sexual assaults in Bangkok each year.

In 2006, a total of 1314 sexual assault cases were seen, of which 530 (40%) were in children under 15 years old. A total of 89% received counselling, and 87% consented to HIV antibody testing and enrolled in PEP programme.

Ms Vitavisini noted, however, that “only 58% of sexual assault victims were seen within 72 hours” and said that both police and public should be provided with more education on the importance of early presentation for PEP following sexual assault.

Although 544 individuals were seen early enough to qualify for PEP, only 141 (36.6%) completed the full 28-day course. In addition, just one in four (26%) individuals returned within three months for the results of the HIV antibody tests. Ms Vitavisini noted the deep “psychological impact of sexual assault, as well as the painstaking wait for confirmation” of their HIV antibody tests and outcome of PEP.

A total of seven individuals were found be HIV-positive: two were thought to be infected prior to their assault and five (0.38%) were thought to be infected following sexual assault.

Ms Vitavisini said that the total cost of the Police General Hospital PEP programme was US$33,242.50 ($25.30 per person) and that this was cost-effective since a second-line HAART regimen costs over 250 times more than the PEP programme.

However, she concluded, the main benefits of the programme is that it “help[s] sexually abused children and women to live their life with confidence according to their rights.”