NEW YORK — A new strain of the bacterium that causes whooping cough immune to vaccines may have appeared in the United States, according to a brief published Thursday in the New England Journal of Medicine.
The brief, filed by officials from the Centers for Disease Control and Prevention and other health authorities, reported that a strain of Bordetella pertussis had been reported in Japan, France and Finland and may have appeared in Philadelphia, where 12 children were hospitalized between 2011 and 2012.