text_1: Chlamydia trachomatis is most prevalent in the UK among sexually-experienced individuals aged 16 to 24.
text_2: Prevalence of HPV types 16 and 18 in women aged 18-20 years was lower in Natsal-3 than Natsal-2 (5·8% [3·9-8·6] vs 11·3% [6·8-18·2]; age-adjusted odds ratio 0·44 [0·21-0·94]).