Authorities are trying to contact thousands of patients vaccinated by two Sydney GPs after vaccines were found to have expired or not been stored properly.
Thousands of patients of a Sydney GP clinic may need to be re-vaccinated after it was discovered some shots were incorrectly stored or out of date.
NSW Health on Wednesday warned vaccines administered by Drs Darrel and Brinda Weinman at their Burwood practice since 2010 may not have been effective.
"We are writing to patients of that practice to ask them to get advice from a new GP on the need for revaccination," Dr Leena Gupta said in a statement.
About 3000 patients have already been contacted but inconsistent record-keeping at the practice has made it difficult for authorities to identify patients and obtain contact details.
Dr Brinda Weinman retired in May, while Dr Darrel Weinman died in October.
NSW Health said it is assisting the Medical Council of NSW and NSW Health Care Complaints Commission in investigating and responding to the incidents.