Millions of women in the UK are suffering the agony of repeat bouts of vaginal thrush and many of them can’t be cured, experts warn.
In a study, researchers examined swabs taken from patients who had suffered at least four episodes of the fungal infection within 12 months — classed as recurrent.
Of these 15 per cent were found to be resistant to the most powerful first line treatment, fluconozole, and other powerful anti-fungals.
It means that in some of these cases, the infection will be near-impossible to treat — meaning women may have to rely on medication to keep symptoms at bay for life.
Over-use of common anti-fungals could be to blame said the scientists behind the research, which has been published in the journal Sexually Transmitted Infections.
Vaginal thrush is common, with three in every four women of reproductive age likely to be affected
White discharge, soreness and itching around the vagina, are all tell-tale signs of the fungal infection
Thrush, also known as candidiasis, is caused by a type of yeast called Candida.
Normally, this lives harmlessly on the body but sometimes it can can grow out of control and damage healthy tissues.
The infection can affect the mouth, throat, penis and vagina and it causes itching, irritation and soreness and sometimes discharge in women.
In recent years there has been concern among skin specialists that some cases are becoming harder to tackle, with patients regularly having to use treatments for many months rather than weeks.
Much like harmful bacteria have become immune to common antibiotics, a similar pattern is emerging with fungal infections.
To understand the scale of the problem researchers examined lab results taken from thousands of UK women with recurrent yeast infections between 2018 and 2021.
The majority were found to be caused by Candida albicans, the fungus usually responsible for vaginal thrush.
But there was a year-on-year increase in other Candida species, of which the most common was Nakaseomyces glabrata, a species that’s resistant standard treatments.
In 2018, around one in 20 cases were due to these ‘other’ species, increasing to one in ten by 2020.
Overall, three per cent of cases were found to be resistant to one of more standard drugs, including fluconozole, rising to nearly 10 per cent in 2020.
Fluconazole is used to treat vaginal thrush, but resistance to the anti-fungal has increased fourfold over the past three years
‘The increase in non-albicans species is of clinical concern as some have intrinsic reduced susceptibility to fluconazole,’ researchers highlighted.
‘Successful treatment of fluconazole-resistant Candida albicans and non-albicans species can be very challenging, and this frequently requires multiple courses of antifungals.
‘Many of these yeasts also had reduced sensitivity to [second line medications] itraconazole and voriconazole, limiting treatment options even further,’ researchers added.
Since 2013, UK primary care guidance has recommended a clinical diagnosis of acute vaginal thrush to be made on the typical signs and symptoms — such as itching and discharge.
Doctors can also test for vaginal pH for signs of a yeast infection and follow it up with treatment such as a single dose of oral fluconazole or clotrimazole pessary, which is a tablet that is inserted vaginally, researchers say.
But there is evidence vaginal thrush is over diagnosed by both medics and patients and researchers suggest that this can lead to the unnecessary use of antifungal treatment, which may have led to resistance developing.
The researchers said: ‘The exact reasons for this increase [in fluconazole resistance] remain unclear, but it follows the introduction of restricted access to fungal cultures for the diagnosis of [vulvovaginal candidiasis] by those working in primary care.
‘A clinical diagnosis, followed by empirical treatment, has been recommended instead. Consequently, we believe this policy of encouraging empirical vaginitis treatment based on non-specific symptoms and signs needs revisiting.’
