This year for the first time, people aged over 65 are being offered one of two influenza vaccines whose effectiveness has been significantly boosted.
All up, there will be six different types of vaccines but the two being recommended for older Australians protect against three viruses and are known as trivalents – they are Fluzone High Dose by Sanofi-Aventis and Fluad by Seqirus. The Therapeutics Goods Administration says they are available now.
In 2017, visits to hospital by patients suffering with flu soared 50 per cent. More than 221,000 flu infections were recorded around the nation – the highest ever – and many who fell sick had had a flu shot.
Last year’s nasty flu season rang alarm bells for health authorities, who determined that standard vaccines were probably not particularly effective in the elderly.
As a result, two vaccines have been developed for this year’s flu season and both are designed to enhance immunity. One is a high-dose vaccine with four times the strength of the standard vaccine, and the other is an “adjuvanted” shot that has a separate compound which also boosts immunity, according to Professor Kanta Subbarao of the Peter Doherty Institute for Infection and Immunity.
Writing for The Conversation, Prof. Subbarao said the effectiveness of seasonal influenza vaccine varied between years.
“(It) is usually around 40 to 50 per cent. But last year’s vaccine was only around 33 per cent effective overall because it was not effective against the A/H3N2 virus though it was effective against the A/H1N1 and influenza B viruses,” she said.
“There are four influenza viruses that cause epidemics: two type A viruses, called A/H1N1 and A/H3N2, and two type B influenza viruses, called B/Yamagata and B/Victoria viruses. In any season, one of the viruses may dominate, or two or even three viruses could circulate.
“Influenza A/H3N2 viruses cause more severe epidemics that affect the entire population, from the very young to the very old. In contrast, influenza B and A/H1N1 viruses tend to cause disease in children and young adults, respectively, sparing the elderly,” she said.
It is no surprise, then, that last year’s flu season was caused by the A/H3N2 virus. According to a Health Department report, the effectiveness of last year’s vaccine was low against that particular virus strain, especially in the elderly.
Those contemplating skipping a flu injection this autumn because of last year’s experience are being warned to rethink. If you are elderly or have a chronic illness, contracting influenza puts you at risk of serious, even deadly, complications.
Medical authorities say that you cannot catch the flu from the vaccine and apart from some local soreness at the point of injection, it will not make you sick. Some people may experience a few temporary side-effects, such as nausea, headache, fever or muscle aches. These usually settle after a few days.
In addition to those aged over 65, people with severe asthma, lung or heart disease, low immunity or diabetes can get their jabs for free. For others it costs less than $25. If your doctor does not bulk bill, there will also be a cost for the consultation. If you choose to be vaccinated by your pharmacist, make sure they are stocking the new vaccines that were released this month.
For more information about the flu vaccine, visit the Immunisation Coalition website.
Did you catch the flu last year even though you were vaccinated? Are you planning on being vaccinated this year?