Kambah Medical Practice GP Suzanne Davey said vaccinating against illness and disease was the easiest way GPs could protect adults, children, the elderly and "immuno-compromised" people from vaccine-preventable infectious disease.

"The risk is far higher if you contract the disease of having a serious complication than from immunisations," she said.

"Living in a community means sharing germs so vaccination protects you from infectious disease."

Dr Davey said in the early part of her career she worked in Cooktown where there was a high unvaccinated population and said she witnessed children die from whooping cough and tetanus. She also pointed to how immunisation programs meant diseases such as polio were either no longer seen or extremely rare.

"In a population with a high unimmunised group of people, the infections can become very prevalent and spread very easily," she said.

She said immunisation was vital to protect people from catching infectious diseases,

Australian Medical Association president Associate Professor Brian Owler said Australian GPs had been crucial in increasing Australia’s rates of immunisation.

“The importance of immunisation from preventable diseases remains a relevant community message amid concerns about patchy immunisation rates across the country and continued rates of immunisation lower than the 95 per cent mark, which provides herd immunity,” he said.

He said rates of illness and death from vaccine-preventable diseases had fallen significantly since childhood vaccinations were introduced in Australia in 1932.

Speaking during the AMA's Family Doctor Week, Assoc Prof Owler said where immunisation levels were low, illnesses such as whooping cough and measles could be spread more easily.

A single case of measles was diagnosed in the territory on Friday, the third in the ACT this year.

Symptoms of measles may include fever, tiredness, running nose, sore eyes and a cough, followed by a rash which appears two to seven days later.

People generally develop symptoms seven to 18 days after being exposed.

Measles could be a potentially serious disease, which was highly contagious among people who were not fully immunised.

The recent confirmed case was the third for the ACT this year, after one in January and another in early February. Before that, Canberra had not had a confirmed infection since 2011.

Recent data from the Australian Childhood Immunisation Register shows the ACT continues to have some of the best vaccination rates in the country, with about 93 per cent of one and two year olds in the territory fully immunised compared with about 92 per cent of five year olds.

More information about immunisations is available from the Australian Academy of Science's website.