(CNN) — Whooping cough has been surging in the United States for months and the latest data from the US Centers for Disease Control and Prevention suggests there are no signs of slowing.
There have been more than 32,000 cases reported so far this year, according to preliminary data from mid-December — about six times more than there were at this time last year and more than there have been since 2014 .
Whooping cough, also known as pertussis, is a very contagious respiratory illness. For many, the bacterial infection starts with symptoms similar to the common cold — a runny nose, sneezing, a low-grade fever and a tickly cough — but a painful, full-body cough can develop after a week or two. These coughing fits can be so severe that they cause patients to vomit or break ribs, and they’re often accompanied by a whooping sound as the person tries to catch their breath.
This coughing can last for weeks or months, and people can spread the infectious bacteria for weeks after the cough develops. However, infections can be mild enough for some that they spread the illness without even knowing they have it.