120% rise in whooping cough cases

Pregnant women and secondary school students are being targeted as part of a public health campaign to boost protection against whooping cough.

The campaign comes against a backdrop of two infant deaths and a doubling of the number of cases of the disease.

Figures from the Health Protection Surveillance Centre show a 120% increase — from 157 to 346 — in the number of cases notified to it for the first 37 weeks of 2012 compared to the same period last year.

In Britain, the worst outbreak of the illness in two decades has caused 10 deaths so far this year in infants under three months. From Monday, women across Britain who are between 28 and 38 weeks pregnant will be offered the vaccination.

Yesterday, the HSE confirmed the two Irish fatalities. It told the Irish Examiner increases in the pertussis infection — more commonly known as whooping cough — were likely, in part, to be due to improved diagnosis, but that there was also “increasing evidence of waning immunity”.

To combat the rise in cases, the HSE last year introduced a pertussis-containing booster for first- year students in some parts of the country. It is now planned to roll this out in all schools in 2012/2013.

This will begin once the HSE has completed the first dose of HPV (cervical cancer) vaccinations.

Pregnant women who have not received the pertussis-containing vaccine within the previous 10 years will also be offered the vaccination after 20 weeks gestation. This is because babies cannot receive the jab until they are two months old.

Vaccinating their mothers before they are born will boost their immunity until they reach the age they can have the injection themselves.

Last month, the National Immunisation Advisory Committee published the new guidelines on the pertussis vaccination of pregnant women.

The HSE said yesterday that “options for additional measures are under review by the HSE in conjunction with and NIAC and the Department of Health”.

Whooping cough is a highly-contagious bacterial disease chiefly affecting children, characterised by convulsive coughs followed by a “whoop”. The illness is more severe, and mortality rates are highest, amongst infants.

Following either infection or vaccination, immunity wanes over one to two decades. Worldwide, over 45m cases occur annually, with over 250,000 deaths.

Illness info

* The highest incidence morbidity and mortality rates occur in infants, particularly in those aged less than two months.

* The source of infection for approximately 80% of infants is a household contact — either a parent or a sibling.

* In recent years there has been an increase in cases among adolescents and adults.

* Transmission occurs by close contact via droplet infection from the respiratory tract of symptomatic individuals.