Self-collection of samples in sex workers works best when screening for STIs

Apr 1 2009

Researchers at the University of Westminster have used a simple and convenient method for screening female commercial sex workers (CSW) for sexually transmitted infections (STIs) without the need for them to attend clinics.

The women were given tampons that they could use to collect their own samples and post them to the laboratory. The results showed that the women in the study found self-collection of samples very easy and much preferred this method of screening for STIs and in addition the testing methods used proved to be more accurate than traditional tests.

Dr Patrick Kimmitt who presented the group’s findings to the Society for General Microbiology meeting in Harrogate (Wednesday 1 April) pointed out that despite their risk of exposure to STIs, female CSW are reluctant to attend clinics for regular screening for these infections. This may be due to unsuitability of opening times, fear of stigma or the false concern of the possibility of being reported to the police. “Point of care testing” delivered at their workplace is more attractive to this patient group.

The study involved 65 CSW, each was asked to complete a questionnaire in which they indicated their preferences for screening and ease of use of sample collection. The samples were processed in the laboratory using a method called PCR (Polymerase Chain Reaction) which rapidly detects a unique DNA sequence in three of the micro- organisms that cause STIs - gonorrhoea, Chlamydia and Trichomonas. For comparison, samples were also collected and screened for these pathogens using traditional laboratory methods. The results showed that all the women found self-collection of samples very easy and much preferred this method of screening for STIs. Furthermore, more cases of gonorrhoea and Chlamydia were found using the PCR method compared to traditional methods.

“If this is seen to be an acceptable method then it could be considered as a possible testing device for other patient groups who also find it difficult, or are reluctant, to access mainstream sexual health screening services, such as women in rural areas, prison screening services or teenagers,” said Dr Kimmitt, “The tampon is a small device that can be easily posted to a central laboratory for processing and is less likely to leak than a urine specimen. It is also small enough for easy storage.”