This dangerous cough threat is already surging ahead of winter

• The spike in cases comes amid shifting policies under Health Secretary Robert F. Kennedy Jr. and the overall lingering skepticism nationwide over vaccines.
• Public health experts say falling vaccination rates since the pandemic and waning immunity are causes of the surge.

Driving the news: Kentucky reported its third infant whooping cough death for the year on Monday.

• The child was unvaccinated, health officials said.
• "We are deeply saddened to learn of another infant death in Kentucky due to pertussis and are concerned by the volume of cases we are seeing throughout the commonwealth," said Steven Stack, the state secretary of Kentucky's Cabinet for Health and Family Services, in a statement.

Cases of whooping cough are on the rise nationwide.

• There have been more than 25,000 cases in the U.S. alone this year, ABC News reports based on CDC data.
• Last year, whooping cough cases hit their highest annual total in a decade.
• Despite the rise, health officials say that many cases of whooping cough go unnoticed and unreported.

Here's what to know about whooping cough.

What is whooping cough?

Zoom in: The illness, formally named pertussis, is a highly contagious respiratory infection that has been rising throughout the country.

• The illness is caused by a bacteria called Bordetella pertussis, which is found in humans, per the CDC.
• The bacteria attach to small, hair-like extensions called cilia on the upper respiratory system. The bacteria then release toxins that damage the cilia, leading to swollen airways.

How does it spread?

Like other respiratory illnesses, whooping cough can spread through the air from one person to another.

• "When a person with whooping cough sneezes or coughs, they release small particles with the bacteria in them," the CDC says.

Symptoms of whooping cough

The respiratory illness has symptoms that change depending on age and vaccination status.

• Typically, symptoms begin with a runny nose and mild coughing.
• After one or two weeks, the cough can become rapid and make a "whooping" sound.
• Some doctors describe it as "a 100-day cough" because of the long-lasting symptoms.
• It can also lead to vomiting and difficulty breathing.

Who is at risk for whooping cough?

Babies who are younger than 1 are at the largest risk for whooping cough and its severe symptoms, the CDC says.

• "The younger the baby, the more likely they'll need hospital treatment," a CDC guide on the illness reads.
• "Whooping cough can even be deadly."

Adults who have pre-existing health conditions that can be worsened by whooping cough are also at risk for severe infections, according to the CDC.

• That includes people who are immunocompromised, or moderate or severe asthma.

How to prevent whooping cough spread

What they're saying: Health officials say people can help stop the spread of the disease through measures such as:

• Washing your hands often.
• Covering your coughs and sneezes.
• Staying home when you're sick.

People can be contagious for weeks. But the CDC says taking antibiotics can shorten the amount of time someone is contagious.

Whooping cough and vaccines

The CDC's website currently advises vaccination against whooping cough for everyone.

• "These vaccines work well, but protection fades over time," the CDC says.

There are two vaccines for whooping cough — DTaP and Tdap.

• The former is recommended for children because it also protects against diphtheria. The latter is recommended for preteens at 11 and 12 years old, and for adults who never received it.

Worthy of your time: Kentucky health officials said none of the infants who died of whooping cough there in the last year had been vaccinated.

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