PGIMER Study Finds Rise in Whooping Cough–Like Infections in North India

A team of researchers at the Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh, has identified a sharp rise in infections caused by a lesser-known bacterium that resembles whooping cough in northern India.

Pertussis, or whooping cough, is a highly contagious respiratory disease that was once a major cause of childhood deaths, with fatality rates as high as 10 per cent in the early 20th century, according to a PGIMER statement.

The findings, published in the Emerging Infectious Diseases journal of the U.S. Centers for Disease Control and Prevention (CDC), are based on the study titled “Emergence of Bordetella holmesii–Associated Pertussis-Like Illness, Northern India, 2019–2023.” The researchers examined 935 suspected cases of pertussis and found that nearly 37 per cent were caused by Bordetella holmesii—a higher proportion than infections linked to Bordetella pertussis, which was traditionally more common.

The steepest surge was observed in 2023, primarily affecting children aged 5–10 years across northern India. Data from PGIMER’s ongoing surveillance programme, active since 2015, showed that while B. pertussis infections dropped from 15–20 per cent to just 2–5 per cent, B. holmesii infections rose significantly.