Australia has been hit by critical shortages of the measles vaccine right at a time when there is a surge in the number of cases worldwide.

Key points: Dr Richard Kidd from the AMAQ said up to half Australia's adult population might not be fully vaccinated

Dr Richard Kidd from the AMAQ said up to half Australia's adult population might not be fully vaccinated The Federal Department of Health says there are "adequate supplies" for the National Immunisation Program

The Federal Department of Health says there are "adequate supplies" for the National Immunisation Program Glaxo Smith Kline says it is working closely with the department to ensure the program is covered

Pharmaceutical manufacturer and primary supplier GlaxoSmithKline (GSK) has advised the Federal Government it is experiencing a "supply constraint" that is impacting on its ability to provide Priorix Tetra and Priorix to the National Immunisation Program and to non-government customers.

Both vaccines have been added to the Therapeutic Goods Administration (TGA) critical shortages list, and the TGA is warning the supply issues are expected to continue until October.

Dr Richard Kidd from the Australian Medical Association of Queensland said GPs across the country had been unable to restock their supplies and were being forced to ration what they have left.

Dr Kidd said the situation was "quite concerning" and "very disappointing".

He said up to half of the adult population might not be fully vaccinated against measles.

"Obviously everyone gets concerned about young children, but older children and adults who get measles can get very, very sick and some people die," he said.

"Other people are left with lifetime disabilities, so it is a problem for everyone.

"If herd immunity drops below 90 per cent, there is a real risk of an outbreak.

"Australia is at the end of a very long supply chain, so stocks may have been diverted to areas of greatest need. It's particularly bad timing."

SmartClinics medical centre in Brisbane's CBD told the ABC it was down to its last 16 vials of measles vaccine.

The centre's clinical nurse Louise Rosengren said they had been advised by its private suppliers that vaccine levels had been widely depleted.

"It is a big concern. We like to think we can help everyone getting vaccination who wants to be vaccinated, but that's not always the case," Ms Rosengren said.

"We don't want to turn anyone away, but we're going to have to."

Glaxo Smith Kline said it was trying to ensure an alternative vaccine was available for children. ( Centres for Disease Control )

The shortage comes as Australians are being urged to check their immunisation history, particularly anyone born between 1966 and 1994, and people planning to travel overseas.

There has been an increase in measles cases around Australia, with 83 notifications by April 5, compared with last year's annual total of 103 cases.

Professor Paul Kelly from the Federal Department of Health said Australia had an alternative vaccine supplier and parents should not be concerned.

"Supplies for the vaccine immunisation program, which supplies free vaccines to children aged 12 months and 18 months, is completely secure," he said.

"In terms of the private markets, so people for example who may be going overseas ... it's not as automatic as it has been previously, because of that issue with one of the suppliers."

On its website, GlaxoSmithKline said it was "working with the Commonwealth Department of Health to ensure that an alternative vaccine will be available so children's immunisations won't be affected".

The department said the shortages related to certain measles, mumps, rubella (MMR) vaccines in Australia, both sponsored by GSK, but alternative options were available.

"Adequate supplies of measles-containing vaccines have been secured for the National Immunisation Program," a department spokesperson said.

"Alternative MMR and MMRV remain available and consumers may wish to discuss alternatives with their doctors."

The company said the shortage was "due to provision of vaccine to measles outbreak control programs in a number of states and territories".

In a statement, Queensland Health said there was no shortage of the MMR vaccine affecting its stocks.