Millions of UK women are currently suffering from thrush or bacterial vaginosis (BV), with numbers likely far higher than usual due to summer heatwaves. Since May, the UK has experienced three heatwaves, and June 2026 was the hottest on record, peaking at 37°C in East Anglia. Warm weather and seasonal habit changes disrupt the vaginal ecosystem, making infections more common.
Why Summer Worsens Thrush and BV
Dr Babak Ashrafi, a GP at Superdrug Online Doctor, explains: 'Warm, humid conditions, increased sweating, spending longer in damp swimwear or gym clothing, and changes to our daily routines can all create an environment that makes vaginal infections more likely.' Thrush is caused by an overgrowth of Candida yeast, which thrives in heat and moisture. Tight or non-breathable clothing traps sweat, encouraging multiplication.
BV results from an imbalance in natural vaginal bacteria, not a fungus. Summer lifestyle changes—like higher sugar intake, more alcohol, and dehydration—can disrupt this balance. 'While enjoying sugary cocktails, barbecues or holidays won't directly cause thrush or BV, diets higher in sugar, increased alcohol intake and dehydration may contribute to changes in the body's natural balance, especially alongside the effects of heat,' says Dr Ashrafi.
Symptoms of Thrush and BV
According to the NHS, thrush symptoms in women include white discharge, itching and irritation around the vulva and vagina, and soreness or stinging during sex or urination. Thrush can also affect other skin areas like armpits and groin. In men, symptoms include irritation and redness on the penis head, white discharge, unpleasant smell, and difficulty retracting the foreskin. Some people have no symptoms.
BV symptoms include vaginal discharge with a strong, fishy smell (especially after sex), and changes in discharge colour (greyish-white) and consistency (thin or watery). Half of women with BV have no symptoms, and it typically doesn't cause soreness or itching.
Impact on Men and Sexual Partners
Men can also experience fungal infections in warm, sweaty areas. Dr Ashrafi notes: 'Although thrush isn't considered a sexually transmitted infection, it can occasionally be passed between sexual partners. Men may experience symptoms such as itching, redness or irritation of the penis, particularly if they're uncircumcised. If either partner develops symptoms, it's sensible to seek medical advice before continuing sexual activity.'
Prevention Tips for Summer
Lovehoney sexual health expert Sarah Mulindwa advises: 'It's sensible to take a few precautions, such as showering before or after sex if you've been sweating heavily, using plenty of lubricant if needed, avoiding harsh soaps around the genitals, and practising safer sex by using condoms with new or casual partners. These can all help reduce irritation and the risk of STIs.'
Dr Afrah Khattak recommends changing out of wet swimwear promptly, choosing breathable cotton underwear, and staying hydrated, especially if drinking alcohol. 'A pharmacist can help with over-the-counter treatment if symptoms do appear. But if it keeps coming back or doesn't clear up, it's worth booking in with your GP or a gynaecologist rather than riding it out summer after summer. Recurring thrush or BV can sometimes point to something else worth investigating.'
