Warnings in NSW of whooping cough outbreak

An outbreak of whooping cough in New South Wales is causing some concern - the NSW Health Department says infection rates have soared from 2,000 cases last year, to 3,800 cases this year, and the increase is more so in some areas.

Health officials believe the increase is to some degree a reflection of low immunisation rates in parts of the state, particularly the north coast and parts of western Sydney.

In some areas many left school before booster shots were given- and also over time protection is known to wane.

While most people in good health will not be too badly affected by the disease it is particularly worrisome for infants and the elderly and also those with a compromised immune condition.

The outbreak follows others in Queensland and other states and the public are being urged to get themselves immunised if they aren't already - experts say while immunisation does not offer complete protection, it will reduce the severity of the disease.

Whooping cough (pertussis) is a highly contagious respiratory infection caused by bacteria, symptoms may start like a cold, with a runny nose and sneezing, and then the characteristic cough develops.

The coughing bouts can be very severe and frightening, and may end with a crowing noise (the whoop) which is often followed by vomiting.

The bacteria usually takes nine to ten days to become evident after exposure and is spread by an infected person coughing or sneezing, contact with infected secretions from the mouth or nose can also pass on the infection.

A person is highly infectious for the first two weeks of their cough and after three weeks of coughing, the person is regarded as non-infectious, even though coughing may last up to three months.

Treatment involves a course of antibiotics which reduces the time a person is infectious to others which need to be given within 21 days of the start of general symptoms or within 14 days of the start of the cough and school, childcare and work and social gatherings are to be avoided during this time.

As the protection provided by childhood vaccination gradually reduces over time, a single booster dose is recommended.