What probably most worries the medical community is the overuse of antibiotics both in humans and animals, which has led to a wide range of resistant bacteria strains. "Super-bugs" are resistant to all known antibiotics. The reemergence of tuberculosis around the world in recent years has caused a sharp rise in deaths from this disease.
在所有原因中，最令醫界擔心的，大概是抗生素的濫用（包括施打在人體及各種家畜家禽體內），導致細菌紛紛出現抗藥性，成為無藥可醫的「超級細菌」。