Infectious conditions, when prolonged, reflect a weakening of the body's defenses against microbial attacks. Infections affecting the kidneys and urinary system are common: they are treated by strengthening the body's natural defenses. Often more stubborn, mycoses require medical assistance, although plants such as garlic (allium sativum) and tea tree (melaleuca alternifolia) can be effective. In the chronic stage, any infection requires treatment that stimulates the entire immune system with plants such as echinacea (echinacea spp). Cystitis, when it affects the kidneys, becomes a serious condition.