Gonorrhea among the over-65s is rising at nearly double the national average with divorce and dating apps blamed for greater promiscuity amongst pensioners.
The number of cases rose by 42 per cent for older people in 2018 compared with the national average of 26 per cent, according to new figures from Public Health England (PHE).
There were around 448,000 cases of sexually transmitted infections (STIs) diagnosed in 2018, an increase of five per cent from 2017.
PHE blamed the rise on people not using condoms correctly, a growth in casual partners, and an increase in testing improving detection of the most common STIs.
But doctors said that many older people were unaware of the importance of sexual health, after being in monogamous relationships for decades and then getting divorced.
Dr Laura Joigneau Prieto, of the online clinic Zava, said: “Lots of information about safe sex and STIs is targeted at younger people, and unfortunately, this means that many people in older generations have missed out on learning about symptoms and how to protect themselves.
“We’ve also seen an increase in the uptake of dating apps across all age groups including over 65s, which has led to an increase in STI diagnoses.
“Additionally, barrier methods such as condoms are often viewed as only for protecting against pregnancy, so can seem irrelevant once you’ve gone through the menopause or had a vasectomy.”
The number of gonorrhoea cases diagnosed in England has reached its highest level in more than 40 years.
A total of 56,259 cases were reported in 2018, up by more than a quarter (26pc) from the previous year and is of particular concern due to the emergence of extensively drug-resistant gonorrhoea, health officials said
Chlamydia remained the most commonly diagnosed STI, accounting for 218,095 - or almost half - of new diagnoses in 2018.
However, the number of chlamydia tests taken by young people dropped by 1 per cent compared with 2017, while among over 65s it rose by 24 per cent.
Dr Olwen Williams, President of the British Association for Sexual Health and HIV: said “Sexually Transmitted Infections affect all ages, it’s important that everyone is aware of the risk of non-condom use, and attend for testing if they have had a change in sexual partner.
“The rises in cases whilst small in actual numbers reflects that sexual activity occurs across the life cycle and we have to respond to this through having sexual health services that are accessible to all.”
Cases of syphilis also increased by 5 per cent to 7,541, and have more than doubled from 2,847 diagnoses 10 years ago.
Dr Gwenda Hughes, head of STI surveillance at PHE, said: "The rise in sexually transmitted infections is concerning. STIs can pose serious consequences to health - both your own and that of current and future sexual partners.
"No matter what age you are, or what type of relationship you are in, it's important to look after your sexual health.”