Sharp increase in Hawke's Bay whooping cough cases

Of the 101 cases of whooping cough notified in Hawke's Bay in 2017, about seven babies had to be hospitalised. Photo / File

Hawke's Bay health professionals are advising pregnant women to get vaccinated for whooping cough in the wake of a national outbreak being declared.

Across the country Ministry of Health figures showed 1315 cases of the disease, also known as pertussis, had been reported since the beginning of 2017.

In Hawke's Bay, 101 cases of whooping cough were notified to public health in the year to December 2017, up from 16 the previous year.

Hawke's Bay DHB paediatrician and medical director Phil Moore said outbreaks of the disease tended to occur once every four years, and that last year's high number of cases was likely to be repeated in the year ahead.

Of those reported last year, about seven babies were hospitalised.

"So that's about 10 per cent needing to be admitted and it tends to be the younger, small babies under one-year-old who become severely ill."

He said over the last 20 years there had been no deaths in Hawke's Bay, but there had been some very sick babies who needed to be transferred to Starship Hospital.

The upward trend was also reflected in the fact that there had been four admissions to the children's ward in the last month, including a five-week-old baby who was discharged last week.

Prevention was the best line of defence against the disease, Dr Moore said, and in the face of the current epidemic he urged pregnant women to get booster vaccinations.

"These are free for women from 28 weeks on and it gives them good levels of protective antibodies that are passed on to the baby through the placenta and breast milk, which can see them through up until the baby's first vaccination at six weeks old."

Vaccinations were given to babies at six weeks, three months and five months old, with a booster at four years old.

In addition, Dr Moore said it was now known that boosters should continue to be given once every 10 years, most importantly for people in high risk professions, such as nurses and other hospital workers who came into contact with young babies.

While symptoms could start with a runny nose, he said in children the disease was associated with long one to two minute coughing spasms, which exhausted the child and sometimes caused them to change colour.

Symptoms were not so violent in adults, however, who tended to express the disease with a nuisance cough that lasted for a long time, but did not tend to interfere with day-to-day activities.

Being highly contagious, concerns about spreading it to vulnerable children had led to the calls for adults who were in close contact with babies to receive a booster.

Although an outbreak had been declared, immunisation rates tended to be high around the country, reaching about 93 per cent of the population, and in Hawke's Bay that was more like 95 per cent, Dr Moore said.

"If it were not for that these mini-epidemics would be a lot worse."