Lab-Based Retrospective 10-Year Analysis Shows Seasonal Variation of Vaginal Candida Infection Rates in Belgium

Candida vulvovaginitis is a frequent condition, and although several risk factors are known, its behavior is still enigmatic. The seasonal influence of climate conditions and living habits on its prevalence was studied. In a retrospective lab-based cohort over 10 years, we studied the prevalence of Candida in 12,941 vaginal cultures taken from women attending a vulvovaginitis clinic. The prevalence of non-albicans and albicans species were compared per month to detect differences in positivity rates in summer versus winter months. Chi-square and chi-square for trend were used. Of the 2109 (16.3%) Candida spp. positive swabs, 201 (1.0%) revealed non-albicans species, varying between 1.0% and 2.0% per month, but without significant monthly differences. Over the 10 years, compared to other months, vaginal Candida was more frequent in June (19.0%, p = 0.008) and less frequent in December (14.5%, p = 0.04). The Candida prevalence was 15.5% in summer (June/July/August) versus 14.0% in the winter (Dec/Jan/Feb, p = 0.04). Change in temperature, dietary habits, and bodily adaptations due to increased amount of sunlight were discussed as potential pathophysiological mechanisms to explain the excess of Candida in summertime. Further confirmatory research would be beneficial. Women at risk for Candida vulvovaginitis should pay more attention to living habits in summertime to avoid recurrences.