Whooping cough cases in Wisconsin are 12 times higher than last year, DHS says

This story was updated to add new information.

Whooping cough cases in Wisconsin are 12 times higher than last year, with case counts reaching pre-pandemic levels, the Wisconsin Department of Health Services said in a news release Thursday.

As of Sept. 13, the DHS had logged 625 confirmed cases of whooping cough, or pertussis, in 2024. That's compared to 51 cases at the same time last year.

So far this year, two-thirds of Wisconsin counties have reported at least one case of the respiratory infection. Children and teenagers between 11 and 18 account for nearly half of all cases reported, though 28 infants have also been diagnosed with the infection, with six of them needing hospitalization.

And those numbers likely don't tell the whole story, according to Dr. James Conway, an infectious diseases expert at the University of Wisconsin-Madison's Global Health Institute. For every reported case, there are likely 10 to 20 other people infected who don't know it yet or probably won't get tested to confirm the case.

"That's what gets public health (officials) really concerned," he said, "When it's as widespread as this is, where 48 counties have had at least one case, that means it's basically kind of everywhere, and that's just the tip of the iceberg."

Here's what to know about whooping cough in Wisconsin, including where you can get a vaccine:

Is there a whooping cough outbreak in Milwaukee?

Like the rest of the state, Milwaukee has had an increase in pertussis cases in recent months, according to Milwaukee Health Department communications officer Caroline Reinwald.

As of Aug. 31, Milwaukee has had 52 reported cases of whooping cough, compared to just one case at the same time last year. The infection surged over the summer, with 35 cases reported between July and August and most of them among children under 18.

The North Shore Health Department, which oversees the northern Milwaukee suburbs, has logged eight cases in the last two months. All of these cases have been among children between 4 and 17, according to North Shore public health officer Becky Rowland.

Wisconsin's outbreak is also on par with nationwide trends: as of Sept. 14, more than 14,500 cases of whooping cough had been reported nationwide, according to data from the Centers for Disease Control and Prevention. That's four times more than had been reported at the same time in 2023 and higher than pre-pandemic levels of the disease, when about 10,000 cases were reported nationally every year.

Why are whooping cough cases rising in Wisconsin?

A combination of lagging vaccine rates, relaxation of pandemic-era masking and social distancing, and back-to-school season is likely to blame for the outbreak, according to Conway.

Mitigating the outbreak will take a "concerted effort" to encourage people to get up-to-date on their vaccines, he said. Amid lower vaccination rates, Conway said he's also concerned about outbreaks of the flu, measles, mumps and respiratory syncytial virus, or RSV, this fall.

"We've had a lot of vaccine fatigue in the general community," Conway said. "A lot of it is not that people are opposed to vaccines. It's that they have to go out of their way to get them, and it's a needle and it hurts."

Conway also emphasized that many of these vaccines, included for pertussis, have been extensively tested for decades.

"Millions and millions of doses of these things have been given," he said. "We've got plenty of evidence and plenty of data that they work really pretty well, and that they're actually very, very safe."

What is whooping cough? Symptoms, treatment, prevention

Early symptoms of whooping cough can look like a common cold, but the infection can intensify into long coughing fits that leave you breathless and making a "whoop" noise, according to the CDC. Severe cases in teens and adults can cause weight loss, loss of bladder control, passing out and rib fractures from severe coughing.

In infants and newborns, symptoms can show up as difficulty breathing, instead of coughing. Severe cases can cause pneumonia, convulsions, brain damage or even death, according to the CDC. In some cases, infants will turn blue from the infection, Stephanie Schauer, DHS immunization program manager, told the Journal Sentinel in July.

Whooping cough is also sometimes called the "100-day cough" because symptoms can persist for weeks, she said.

"Once people start coughing, they can't stop, (and it's) often accompanied by vomiting at the end," Schauer said. "These can happen for up to 15 times in a day."

If you start feeling symptoms of whooping cough, Schauer recommended isolating at home and seeing a health care provider to get tested for the infection. A doctor will likely prescribe a five-day cycle of antibiotics that will stop you from being contagious.

Who should get a whooping cough vaccine?

In terms of prevention, the best way to avoid contracting whooping cough is to get vaccinated, public health officials said.

Here's a rundown of which vaccines children and adults should get for pertussis, according to the Milwaukee Health Department:

• Children should receive five doses of the DTaP vaccine between two months and 6 years.
• Adolescents between 11 and 12 should receive one dose of the Tdap vaccine.
• Adults who have never had a pertussis vaccine should receive one dose of the Tdap vaccine.
• Pregnant people should receive a Tdap vaccine between 27 and 36 weeks of pregnancy. This helps protect the newborn before they're old enough to get the DTaP vaccine. New parents should also make sure people interacting with their baby are up-to-date on vaccines.

Where can you get a whooping cough vaccine in Wisconsin?

You can see your health care provider for a whooping cough vaccine.

The DHS also provides vaccines free and regardless of insurance status through its Vaccines for Children and Adults programs.

You can find a list of adult vaccination locations here, and a list of vaccination locations for children and teenagers under 19 here. Clinics are located throughout the state.