Chlamydia

Chlamydia (genital chlamydial trachomatis) is the most commonly diagnosed bacterial sexually transmitted infection in England, with rates substantially higher in young adults than any other age group. It causes avoidable sexual and reproductive ill-health, including symptomatic acute infections and complications such as pelvic inflammatory disease (PID), ectopic pregnancy and tubal-factor infertility.

The National Chlamydia Screening Programme (NCSP) promotes opportunistic screening to sexually active young people aged under 25 years.

In June 2021 changes to the programme were announced with a focus on reducing reproductive harm of untreated infection through opportunistic screening offered to young women aged under 25 years.

UK Health Security Agency (UKHSA) recommends that local authorities should be working towards the revised female-only PHOF benchmark detection rate indicator (DRI) of 3,250 per 100,000 aged 15 to 24 (Female).

The following findings are based on 2022 data:

• In the Lancashire-12 area the proportion (11.3%) of the population aged 15 to 24 screened for chlamydia, in specialist and non-specialist sexual health services, is significantly lower than the England rate (15.2%). In Blackburn with Darwen (10.1%) and Blackpool (13.7%), also, this proportion is significantly lower than the England rate.
• The recent trend shows a decrease in the proportion of 15-24-year-olds screened for chlamydia in the Lancashire-12 area overall and nine districts in the area.
• Preston (18.1%) has the highest screening rate in Lancashire-12 and its rate is better than the England rate. 
• Lancashire-12 area's rate (1,531) of chlamydia detection per 100,000 15-24-year-old females is lower than the recommended target of 3,250 and is decreasing; this rate is below the England rate (2,110).
• Blackburn with Darwen's rate (1,825) of chlamydia detection per 100,000 females aged 15 to 24 is similar to the England rate and Blackpool's rate (2,528) is better than the England rate.
• In 2022, there were 3,179 chlamydia diagnoses in the Lancashire-12 area. Lancashire-12 area's rate (257 per 100,000 population) of new diagnoses is lower than the England rate (352).
• Blackburn with Darwen's (263) chlamydia diagnoses rate is also lower than the England rate, while Blackpool's (399) chlamydia diagnoses rate is higher than the England rate.
• In Preston (503) chlamydia diagnoses rate per 100,000 population is significantly higher than the England rate and in Lancaster (338) it is similar to the England rate; in the other ten districts it is lower than the England rate.

For county and unitary data and further information please see below

Page updated June 2023