A wave of whooping cough infections is continuing to worsen nationwide, data from the Centers for Disease Control and Prevention suggests, with weekly reported cases now accelerating to the highest levels seen in the U.S. for years.
At least 259 pertussis cases were reported during the first week into August, the CDC now tallies , up from 215 weekly cases towards the end of June. Pennsylvania has reported 1,489 cases so far this year, the most of any state. New York has reported the next largest total of cases, at 1,266 infections.
The increase comes as CDC officials have been warning for months of a return to the pre-pandemic trends of the illness. Whooping cough is caused by the bacteria Bordetella pertussis, which had plummeted to record lows during the COVID-19 pandemic, likely due to more people at the time wearing masks and staying home from schools and offices. So far this year, a total of more than 10,000 pertussis cases have been reported by health departments.
By mid-June, total cases this year reached more than triple what they were compared to the same time last year. Reported cases this year are also now higher than they were right before the pandemic, which had reached around 8,000 cases by early August of 2019. Many diseases that spread from person-to-person through the air like pertussis saw rates of infections drop during the COVID-19 pandemic.
"It's likely mitigation measures used during the pandemic (e.g., masking, remote learning) lowered transmission of p.