The figures, collected by Statens Serum Institut (SSI), have resulted in the medical and disease research institute declaring an epidemic of the illness.

At 1,323 recorded cases, the incidence of the disease is over three times normal levels.

SSI department doctor Peter Henrik Andersen said that the increase in cases is spread across all age demographics, but particular attention should be paid to small children.

“Whooping cough can be serious for small children. Doctors are therefore advised to be particularly alert to potential cases of whooping cough in patients with attacks of dry coughing,” Andersen said in a press statement issued by SSI.

“That applies in particular to smaller children but also to older children and adults who can be a source of infection for smaller, unprotected children,” he added.

“It’s important that parents are aware that small children, in particular, are vaccinated on time. Additionally, unvaccinated children under the age of 24 months who have been in contact with someone with whooping cough can be offered preventative antibiotics,” the SSI specialist continued.

Whooping cough can be dangerous for small children due to their narrower airways, in which hardened mucus can collect and cause breathing difficulties.

Long coughing fits can also result in the child not taking in sufficient oxygen.

In a statement, health minister Magnus Heunicke advised parents to ensure their children follow the vaccination programme against the disease. Vaccines are given at the ages of 3, 5 and 12 months and at 5 years.

“We have a vaccine that works. That’s why I feel it’s important to remind all parents of the responsibility they have – remember to get your small children vaccinated,” Heunicke said.

“That way we can all contribute to limiting the consequences of epidemics such as the one we are seeing now,” he added.

Whooping cough is caused by a bacteria, Bordetella pertussis, which is considered to be one of the most contagious in Denmark. The time between infection and the onset of symptoms is around 5 to 15 days.

Symptoms initially resemble a cold and light cough lasting around two weeks, before more severe and dry coughing fits begin. The dry coughing can last for as long as 10 weeks.

Small children can suffer up to 30-40 coughing fits per day as a result of the disease.

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