The yeast Candida albicans can cause itchy, painful urinary tract and vaginal yeast infections. For women in low-resource settings who lack access to healthcare facilities, these infections create substantial social and economic burdens. Now, researchers have developed color-changing threads that turn bright pink in the presence of C. albicans. When embedded in tampons or sanitary napkins, they could allow women to quickly and discreetly self-diagnose vulvovaginal yeast infections, the researchers say.