SYDNEY — Australians face the risk of catching diseases not seen in wide circulation for decades as childhood vaccination rates slip into serious decline, AAP reported Jan. 21.

And the return to school was likely to see a resurgence of H1N1 flu in children unless they were vaccinated, the chairman of the Australian General Practice Network has warned.

The vaccination rate for traditional childhood diseases is at a seven-year low, with 83 percent of 4-year-olds covered — below the 90 percent that assures good communitywide disease protection.

Network chairman Dr. Emil Djakic said the drop in immunization was expected to continue, along with an increase in potentially deadly diseases.

"Immunization rates among 4-year-olds have reduced to about 83 percent ... and they are likely to continue to drop," he said Jan. 20.

The risk to the community was high, he said, pointing to a whooping cough epidemic last year that killed one child and made many more severely ill.

Australia's regimen of childhood vaccinations prevents the spread of whooping cough, also called pertussis, along with diphtheria, tetanus, polio, mumps and rubella.

Affected children can infect vulnerable adults, particularly pregnant women, the elderly, the obese and Aborigines.

"These illnesses are often much worse for adults, and adults with a chronic condition are at a high risk of serious complications," Djakic said.

"These diseases are still in our community and will re-emerge and strike, and strike very cruelly."

Djakic said part of the problem was the federal government's ending of an incentive scheme that paid general practitioners to set up vaccination reminder systems.

The scheme ensured parents were told when their children were overdue for injections, particularly as they reached their preschool years.

Djakic said another worrying reason was anti-vaccination groups, usually on the Internet, who opposed immunizing children on the basis of "very questionable data."

"As a result it is harming the image of immunization and directly leading to harm in Australia's children," he said.

Djakic urged parents to ensure children were fully vaccinated before school starts.