National Chlamydia Screening Programme
Genital Chlamydia trachomatis infection is the most commonly diagnosed bacterial sexually transmitted infection in genitourinary medicine (GUM) clinics in the United Kingdom. The number of diagnoses of uncomplicated genital chlamydial infection in GUM clinics has risen steadily since the mid-1990s, and in the UK diagnoses rose by 9% (95 879 to 104 155) between 2003 and 2004. In 2004, the highest diagnostic rates of genital chlamydial infection were among 16-19 year old females (1 310 / 100,000) and 20-24 year old males (1,026/100,000) 1.
The prevalence is highest in young sexually active adults, especially women ages 16 to 24 years and men ages 18 to 29 years 2 3 4. As most people are asymptomatic, large proportions of cases remain undiagnosed 2 5. Untreated genital chlamydial infection may have serious long-term consequences, especially in women in whom it is a well-established cause of pelvic inflammatory disease (PID), ectopic pregnancy and infertility 2 6 7. The annual cost of chlamydia and its consequences in the United Kingdom is estimated to be more than £100 million.
There is growing evidence from other countries that active case finding for genital chlamydial infection, through targeted screening of at-risk populations, can significantly reduce the morbidity associated with this infection 8 9 10 11 12 and its sequelae 13 14 15 16. The US piloted a regional chlamydia screening programme, known as the STD-related Infertility Prevention Project or IPP, in 1988 and demonstrated a 65% decline in infection in family planning clinic attenders in the first 8 years of screening 11. Sweden also observed similar declines after implementing widespread screening 12. Two randomised controlled trials, in the US and Denmark, halved incident PID cases after 12 months of screening for chlamydia among asymptomatic women 13 16. Economic analyses have demonstrated the cost-benefits and cost-effectiveness of chlamydia screening 2 17 18 19 20 21 22 23.
The Chief Medical Officer’s (CMO’s) expert Advisory Group on Chlamydia trachomatis was set up in November 1996 to advise on the issues associated with screening for genital chlamydial infection. The report concluded that chlamydia screening met the criteria for public health intervention and called for the government to take action towards establishing a national screening programme 2.
Following on the advice of the CMO’s report, the DH funded a pilot study to determine the feasibility and acceptability of opportunistic chlamydia screening in two sites in England (Portsmouth and the Wirral). Testing was offered to all sexually active young women attending a range of health care settings, including general practice and family planning / contraceptive clinics, regardless of whether they had symptoms 24. Acceptance and uptake of testing was high (more than 75%) and approximately 50% of the eligible population aged less than 25 years in those areas was tested between September 1999 and August 2000 25. Prevalence of infection in 16-24 year old women was 9.8% in Portsmouth and 11.2% in the Wirral 3. In Portsmouth, 18-year old women and in the Wirral, 20-year old women had the highest peak prevalence, 13.0% and 13.6% respectively 3. In both sites, most of these individuals would have been unaware of their infection and therefore at risk of developing chlamydial complications.
A plan to begin implementing national screening for chlamydia from 2002 was included in the DH National Strategy for Sexual Health and HIV 26. The subsequent strategy implementation action plan 27 outlined plans for the phased implementation of a NCSP beginning with an initial 10 areas in England, building on the learning from the successful pilot study. In January 2004, the DH announced a further 16 programmes, bringing screening coverage to 25% of all Primary Care Trusts (Figure 1). In November 2004, the publication of the public health white paper 28 selected chlamydia screening as a priority area with £80 million allocated over three years (till March 2008). Full national coverage was also expedited for completion by March 2007. The National Chlamydia Screening Programme (NCSP) in England is an opportunistic screening programme for genital chlamydial infection, targeting women and men under 25 years of age, who have ever been sexually active, attending a range of health care and nonhealth care settings.
This local chlamydia screening programme covers Brighton & Hove City and Mid-Sussex PCTs.
The programme conducts opportunistic screening on sexually active under 25 year olds who would not normally request a chlamydia test. The screening takes place in a variety of community settings, including GP surgeries, youth centres, schools, colleges, clinics, and pharmacies. Our target is to test 17% of the local 15-24yr old population. All patients found to be positive will be treated and managed as detailed. Our aim is to reduce the prevalence of chlamydia in Brighton & Hove and Mid-Sussex, to improve sexual health awareness and to reduce the costly sequelae associated with genital chlamydial infection.
References
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