Whooping cough cases have gone up in the U.S. compared to last year, according to new statistics from the Centers for Disease Control and Prevention (CDC) this week.  There have been 14,569 confirmed cases of whooping cough so far this year, according to CDC numbers shared on Thursday. That is four times as many cases compared to 2023, when 3,475 cases were registered nationwide.  Experts and officials chalk up the surge to missed vaccinations during the COVID pandemic as well as mitigation measures such as masking requirements that lowered transmission of the infection. “With the increase in vaccine hesitancy that has been going on since the Covid-19 pandemic, we’re seeing outbreaks occurring in kids who are not vaccinated,” Dr. Tina Tan, president-elect of the Infectious Diseases Society of America, told NBC News.  Vaccines that protect people against whooping cough, also known as pertussis, are called DTap and TDap. The disease normally kicks in roughly a week after people first get exposed to it by another person. Patients tend to struggle to breathe after experiencing consecutive coughs. The CDC said in late July this year that the country’s whooping cough cases are returning to pre-pandemic levels. The government agency added that babies younger than one-year-old are at the highest risk of getting pertussis and developing “severe” complications. Around one-third of babies in that age range who get whooping cough end up needing treatment in the hospital, according to the CDC. The most common complications for them are Apnea and Pneumonia.  There were 291 cases reported during the week of Sept. 14. That week, the state of New York, excluding New York City, had the most cases with 44. Oklahoma had 40 while Ohio had 39. Pennsylvania had 38, according to the CDC.  “We’ve been seeing increasing amounts of disease occurring in adolescents and the adult population because they’re not getting vaccinated like they should,” Tan said.