Bay whooping cough epidemic

There is an outbreak of highly infectious whooping cough in SA, despite it being a vaccinepreventable disease.

The National Institute for Communicable Diseases (NICD) has declared a whooping cough epidemic in the Nelson Mandela Bay health district in the Eastern Cape.

It detected 116 cases in the Port Elizabeth region in the first two months of 2019.

Babies are most at risk of infection and death because they cannot be vaccinated against whooping cough before they are three months old.

The NICD said it also looked for pneumonia and flulike outbreaks in five provinces, and in 2018 reported a spike in whooping cough in all of them – Mpumalanga, Gauteng, KwaZulu-Natal, the Western Cape and North West.

A vaccine for whooping cough, or pertussis, is given at six, 10 and 14 weeks of age, with a booster at 18 months.

Scientists say low vaccination rates may be one reason for the spike in cases.

A world-renowned vaccine expert and professor of vaccinology at Wits University, Shabir Madhi, said the outbreak was due to a combination of factors, among which was poor vaccine coverage.

“There has also been an increase in pertussis in infants younger than three months, who are too young to be protected by immunisation and develop the most severe disease,” Madhi said.

Because babies are most vulnerable, health authorities have been vaccinating pregnant mothers in the Port Elizabeth area to protect their unborn children, the NICD said.

At least three babies died from pertussis in 2018, the institute reported in a diseases communique.

According to the head of the NICD’s Centre for Respiratory Disease and Meningitis, Associate Professor Cheryl Cohen: “The number of notified cases is always a minimum estimate of the number of cases of disease, because of various factors such as persons not seeking healthcare and the healthcare worker not considering the diagnosis or the case not being notified [reported].”

Cohen said the NICD was investigating whether the children who had contracted pertussis in the Eastern Cape had been vaccinated.

“The NICD is working with local public health authorities in the relevant districts to collect vaccination history from the pertussis cases involved in the Eastern Cape outbreak.”

Estimates had shown the vaccine rate was too low.

“In 2016, Statistics SA estimated the coverage of the pertussis-containing vaccine to be 65% for the third dose of the vaccine, which is below the World Health Organisation’s (WHO) recommended target of more than 90% coverage.

“It is possible insufficient vaccination has contributed to the increase in cases.”

SA authorities do not know what percentage of children are vaccinated against diseases including whooping cough, measles, polio and tetanus.

“We don’t have really good data on vaccine coverage. It’s wobbly,” pharmacologist Andy Gray from the University of KwaZulu-Natal said.

He said there were questions about the accuracy of health records and how to calculate the vaccine rate.

Madhi said the WHO estimated that in SA about 75% of toddlers received the pertussis vaccine and about 73% of children were vaccinated against measles, one of the most infectious diseases in the world.

“This is much lower than national department of health estimates of about 90%.”

He said there were limitations in both the department of health and WHO estimates, and a proper nationwide census to determine vaccine coverage was needed.

Health minister Aaron Motsoaledi launched a vaccine census two weeks ago. –

‘The NICD is working with local public health authorities to collect vaccination history’ Cheryl Cohen

NICD CENTRE FOR RESPIRATORY DISEASE