An urgent need for chlamydia screening among young people has been highlighted by the Dublin Well Woman Centre after it emerged that 20 per cent of women aged under 20 who attended a clinic in Coolock tested positive for the sexually transmitted infection (STI).
At another clinic, on Liffey Street in the city centre, 14 per cent of those aged under 20 had the infection. Chlamydia testing has been offered to young women attending the centre's clinics since the start of 2005.
Up to 70 per cent of people with chlamydia experience no symptoms, but if it goes untreated in women it can cause pelvic pain and damage to the Fallopian tubes, which can result in ectopic pregnancy and infertility. It is the most common bacterial STI worldwide.
The medical director of the Well Woman Centre, Dr Shirley McQuade, said it was a public health issue that needed to be addressed urgently. It was "incredible", given evidence of such high infection rates, that public health doctors were not addressing the problem, she said.
Because there are no prevalence figures for chlamydia in Ireland, nobody knows how many people are infected. Dr McQuade said statistics that were emerging suggested "a huge underdiagnosis throughout the country".
For example, the Health Protection Surveillance Centre (HPSC) recorded just 2,258 cases of chlamydia in 2004. Yet in 2005, the three clinics run by the Well Woman Centre in Dublin diagnosed 238 cases - or one-tenth of the national figure - once it started to encourage people to be tested. "This suggests there are vast areas where people are not being offered testing at all," Dr McQuade said. In one entire health board area, there were no recorded cases in 2002.
The Well Woman Centre found much higher rates among young women aged under 25 than in older age groups and the problem appears to be greater among women from poorer socio-economic backgrounds.
The statistics compiled by the centre are based on 9,206 chlamydia tests carried out at three clinics over four years from 2002 to 2005. Among women aged 35 to 39, the rate in all three clinics was less than 6 per cent. At the Pembroke Road clinic in a more affluent area of south Dublin, the rate among women under 20 was just 4 per cent.
The concerns expressed by Dr McQuade about chlamydia and the lack of information on its prevalence in Ireland are not new. In October 2005, a report entitled The Need for Chlamydia Screening in Ireland was produced by the scientific advisory committee of the HPSC.
It pointed out that because most people with the infection do not have any symptoms, screening "is an essential component of control programmes". It concluded that "data from Irish research is urgently required" to establish the prevalence of infection in different sub-populations and to inform policy on the need for screening.
Since then, the HPSC has commissioned the Health Research Board to undertake a pilot study to examine the most effective way to screen for chlamydia.
Funding of €500,000 has been allocated for this research. It is not expected to be completed for about two years however, as there must first be a tendering process before the research contract can be awarded.
An expert steering group - with members from Ireland and abroad - has been appointed to oversee the study. Dr Fidelma Fitzpatrick of the HPSC said this research was "an important first step" as there were a number of issues that had to be addressed.
She said an approach to screening that was acceptable in one country might not be successful in a different country. Another issue concerns the procedure that would be followed in contacting the previous sexual partners of a person diagnosed with chlamydia.
Given that this research will take two years, there is no possibility of screening being introduced for a number of years. In the meantime, many young people will be unaware they are infected and will infect others if they engage in unprotected sex. The infection can be passed on in a single sexual encounter.
Chief executive of the Well Woman Centre, Alison Begas, said one factor contributing to high levels of chlamydia among women under 20 was a lack of negotiating skills to insist that condoms were used. In addition, people were having sex younger and with more partners.
If chlamydia is detected early it can be treated, but Ms Begas fears that people are being discouraged from getting tested because public services are so overstretched. Getting tested should be made as easy as possible, but in reality it is very difficult unless people can attend private clinics such as the Well Woman Centre.
An STI clinic at the Mater Hospital in Dublin sometimes has to close its waiting lists because it cannot cope with demand. At St James's Hospital people have had to wait for up to eight weeks for full STI screening.
In Britain, clinics operate on the basis that people should be given appointments within 48 hours. If a person is diagnosed with one STI they should immediately be tested for all other STIs.
The Well Woman Centre points out that a urine sample is all that is required to test for chlamydia and it encourages all women who attend the centre to be tested. The Coolock clinic accepts medical-card holders.
If chlamydia is not detected early it can have devastating consequences. A study in Sweden found that just under 7 per cent of women with chlamydia were infertile. "Some women don't realise they have it until they try to start a family," said Ms Begas.