HONG KONG—A mutated strain of bacteria is apparently behind an outbreak of scarlet fever in Hong Kong that has killed two children and sickened more than 600 people so far this year. Over the past decade, Hong Kong has typically recorded 100 to 200 cases annually with no deaths. Young adults, not usually affected by the disease, are now becoming infected. And neighboring parts of southern China and Macao are also seeing more scarlet fever cases, according to Hong Kong's Department of Health.
University of Hong Kong microbiologist Kwok-Yung Yuen says an analysis of a draft sequence of the genome suggests that the strain acquired greater virulence and drug resistance by picking up one or more genes from bacteria normally found in the human oral and urogenital tracts. He believes that the overuse of antibiotics is driving the emergence of drug resistance in these bacteria.