Staphylococcus aureus, also known as golden staph, is one of the most common skin infections of humans. Vaginal colonisation is a bit less common, but does happen, as part of aerobic vaginitis.
Pseudomonas aeruginosa can cause vulvovaginal and urinary tract infections, but tends to prefer other locations on the human body to infect.
Candida albicans is a common cause of vulvovaginal yeast infections in women. The following essential oils have been demonstrated to inhibit (not necessarily kill) C. albicans: Anethum graveolens (dill) Artemisia dracunculus (tarragon) Artemisia sieberi (desert wormwood) Citrus aurantifolia (Tahitian lime) Communis hominis Eucalyptus globulus (Tasmanian blue gum) Foeniculum vulgare (fennel) Lavandula stoechas (French lavender) Mentha spicata (spearmint) Pelargonium
Enterococcus faecalis is naturally extremely hardy and highly antibiotic resistant, causing aerobic vaginitis and urinary tract infections.
Escherichia coli is found in most mammals, with most strains harmless (or even probiotic), but others cause food poisoning, urinary tract infections, and vulvovaginal infections.