Pertussis Cases Spike in November

Six times as many cases of pertussis were reported in the United States for the week ending November 16, 2024, as the same week in 2023, according to new data from the Centers for Disease Control and Prevention (CDC).

The numbers reflect a return to pre-pandemic trends, but overall, pertussis cases for 2024 so far have surpassed those seen prior to the pandemic in 2019, according to the CDC.

Of the 434 cases reported for the week ending November 16, 2024, a majority (109) occurred in the East North Central region, mostly in Ohio (93). Another 70 cases occurred in the West North Central region, with 32 cases and 37 cases in Missouri and Nebraska, respectively.

None of the 75 cases in the Middle Atlantic region occurred in New Jersey or New York City; 38 were reported elsewhere in New York, and 37 in Pennsylvania. The South Atlantic region reported 55 cases, including 29 in Florida. The East South Central and West South Central regions reported 11 and 20 cases, respectively. The Mountain and Pacific regions reported 31 (20 in Arizona) and 47 (20 in Washington state) cases, respectively.

The CDC tracks pertussis cases through a national surveillance system, but many cases are likely unrecognized and unreported, according to the CDC.

Although vaccines for pertussis (whooping cough) provide protection, their effectiveness decreases over time, and the CDC expects rates to increase in vaccinated and unvaccinated populations as case levels rebound with the lifting of pandemic mitigation strategies such as masking and remote learning.

Recent CDC data reported by Medscape Medical News showed an association between lower vaccination rates and this year’s uptick in pertussis cases.