People working with or caring for young children (particularly parents and grandparents) should also have a booster immunisation to reduce the chance of spreading the disease.

So far this year there has been 108 cases notified in the Hunter New England area but traditionally the number increases in the winter months.

In 2007 there were 264 cases of whooping cough (pertussis) compared with 537 in 2006 and 561 in 2005.

Public health physician David Durrheim said whooping cough can be a serious disease for people of any age, especially babies.

"Pertussis is very infectious and can easily be spread among people who have close contact. Many babies admitted to hospital with whooping cough catch it from a parent or close family member," Dr Durrheim said.

"Unfortunately being vaccinated or having had whooping cough does not provide lifelong immunity. Therefore many people who care for young children no longer have immunity even if they were vaccinated as children.

"Women that contract whooping cough in the last weeks of their pregnancy may pass it on to their vulnerable newborn child if they are not diagnosed or treated."

Winter makes diagnosing whooping cough more difficult as it usually starts with a runny nose, mild fever and tiredness like many other respiratory illnesses.

Coughing then develops into bouts which may be followed by a deep gasp or 'whoop'. Young children may stop breathing during the coughing attacks and require hospitalisation.

"Apart from keeping small children and babies away from those with a coughing illness, the best way to protect them is to ensure their vaccinations are up-to-date," Dr Durrheim said.

Vaccinations for pertussis are given at 2, 4 and 6 months of age. A booster should be given at 4 years of age and again between 12-17 years of age. Vaccinations of parents and carers of children reduces the risk that they may pass whooping cough on.