CANBERRA, Oct. 7 (Xinhua) -- Cases of influenza in Australia have dropped more than 80 percent in a single year, government data has revealed.
There were 40,000 diagnosed cases of the flu in Australia between January and September 2018, an 83 percent drop from the 230,000 cases in the same period in 2017.
Experts have attributed the dramatic decline to more people being vaccinated against influenza and a more effective vaccination being used this year.
"It's a bit of science and a bit of luck, really," Paul Kelly, the Chief Health Officer of the Australian Capital Territory (ACT), told the Australian Broadcasting Corporation (ABC) on Saturday night.
"We really try to predict what's going to happen to a virus that we know changes itself quite quickly sometimes -- nine months out from the next flu season."
The flu vaccine is revised every year by a panel of World Health Organization (WHO) experts who consider recent patterns of flu epidemics before making recommendations about the composition of the vaccine.
"Every year the health authorities choose to keep some of the strains from the previous year and add one or two new strains to substitute for a new strain -- and it's basically a very intelligent, well-researched guess -- but ultimately a guess," Antonio Di Dio, president of the Australian Medical Association in the ACT, said.
"Last year was the first year for a long time that the flu injection was not nearly as effective as it usually was because the most virulent strains we had in Australia were not completely covered by the vaccination. This year they got it right."
