On Mar. 25, 2026, according to the latest data published by the World Health Organization (WHO), globally, 941,582 cases of pertussis were reported in 2024, representing a 5.8-fold increase compared to the number of cases reported in 2023 (n= 163,388 cases). The highest proportion of cases was recorded in the WHO regions of the Western Pacific (n= 593,659 cases) and Europe (n= 298,612 cases).

In the Americas Region, there was a gradual decline in the number of cases reported annually between 2015 and 2019, and again in 2021–2022, when the number reached its lowest point at 3,284 cases. Subsequently, a significant increase in cases was recorded between 2023 (n= 11,202 cases) and 2024 (n= 66,184 cases), with a moderate decline during 2025 (n= 46,870 cases).

In the Americas Region, 2012 saw the highest number of cases in the decade, with 72,328 reported cases of pertussis. Since 2013, there has been a progressive decrease in the number of cases reported annually in the Region until 2022, when it reached its lowest point with 3,283 cases, and then in 2023 it increased to 4,139 cases.

Pertussis is also known as whooping cough. It is a highly infectious bacterial disease involving the respiratory tract. It is caused by a bacterium (Bordetella pertussis or Bordetella parapertussis) that is found in the mouth, nose, and throat of an infected person. Symptoms usually appear 7 to 10 days after infection but may also appear up to 21 days later. Initially, symptoms resemble those of a common cold, including sneezing, runny nose, low-grade fever and a mild cough.

Within two weeks, the cough becomes more severe and is characterized by episodes of numerous rapid coughs, followed by a crowing or high-pitched whoop. These episodes frequently end with the expulsion of a thick, clear mucous, often followed by vomiting. They initially occur at night and then become more frequent during the day and may recur for one to two months. In young infants the typical ‘whoop’ may never develop, and the coughing fits may be followed by brief periods when breathing stops.