A bad flu season is overdue. Should we fear the ‘Aussie killer’?

As if the Australian cricket team rolling us over in the Ashes tests wasn’t bad enough, another export from the antipodes may about to make our lives even more miserable this winter. If recent press headlines are to be believed, we are about to be consumed by ‘Aussie Killer Flu’ and although there is no need to man the barricades just yet, there is some science behind the hype and doctors are genuinely concerned about what the next few weeks may bring.

This anxiety stems from the fact that the recent Australian flu season killed two and a half times more people there than usual. The particular virus involved is the Influenza A strain known as H3N2, and a mutated variation which means that the Australian vaccine used there (which was chosen to prevent its infection) has unfortunately been less effective than anticipated in preventing an outbreak.

This highlights two major weaknesses we have in our annual fight against flu (which is estimated to kill more than 12,400 people over the age of 65 each year in the UK). We essentially need to guess which actual particular type of flu virus is going to hit a year in advance, and the flu virus itself can capriciously evolve and mutate over the course of a year and whilst travelling across continents, rendering it potentially immune to a well-intentioned flu jab. This has led to the concern that by the time the Australian flu strain reaches us here in the UK it may have mutated just enough to make this year’s UK vaccine completely ineffective.

None of this mattered to residents of Florence in the 18th Century, citizens who coined the term ‘influenza’, as they felt that their annual outbreak of flu was actually inextricably linked to the influence of the stars and planets (‘influenza di stele’) and the cold weather (‘influenza di freddo’) but in fact humans probably acquired the disease some 6,000 years ago when settlements were beginning to flourish, people were living in tightly-knit communities whilst also herding livestock in close-proximity. Other favourable factors for the spread of flu are a low temperature and low humidity – such as is found in the winter months when family members are huddling together during this festive time in our homes.

Last season, the UK experienced a relatively average level of flu outbreaks with the predominant flu virus strain again being the A/H3N2 strain. However, provisional end-of-season vaccine effectiveness figures for 2016-17 suggest ‘no significant effectiveness of the flu vaccine in the over 65 age group’ – i.e. those who are most at risk of further health complications and even death from flu.

Flu is not an insignificant disease. There are actually multiple proven reasons as to why vaccines may not be as effective as we would like them to be – these include the natural decline in our immune defences as we grow older, a mismatch between the actual flu vaccine chosen and the circulating flu strain in the environment, and also the fact that some people consciously decline their annual flu jab, often wrongly believing that it causes the flu (it cannot). The main aim of any successful public health flu protection campaign must therefore be offering and giving better vaccines capable of eliciting an improved immune response to actually protect against influenza infection.

Increasing vaccination rates is possible through better information campaigns, and a higher vaccine dose (essentially packing more ‘stuff’ into the syringe) is plausible too but no such vaccine exists in the UK, although one is licensed in the US.

This leads us onto the next generation of flu vaccine, known as adjuvanted vaccines that have recently become licensed in this country. The UK’s Joint Committee on Vaccination and Immunisation (JCVI) who drive Britain’s vaccination protocols have just announced they have agreed that the available evidence indicates that adjuvanted flu vaccines are more effective in people aged 65 and over compared to influenza vaccines currently used in the UK, and that switching to adjuvanted vaccines for the elderly is both highly clinically effective and highly cost effective.

So what is an adjuvanted vaccine? Essentially this is a normal vaccine that has had added to it a naturally-occurring compound. All the compound does is to effectively signal to the body to produce more flu-specific antibodies to help prevent infection. The adjuvanted vaccine has actually been available in other countries including the USA, Canada, Italy, Germany, Spain, and Australia for many years (in some cases for over 20 years). This vaccine (called Fluad and licensed for people aged 65 and over) is available for GPs to order now for the 2018-19 season.

Unfortunately, if the forecasts are correct, we are now overdue a bad flu season. The last bad season was in 2009, with 1999 being worse still, and with our NHS services often stretched way past capacity consistently even in our ‘normal’ winters, to say that any serious flu outbreak will be bad news is a colossal understatement of somewhat heroic proportions. If we do get a good toss of the proverbial coin, and a ‘bad flu season’ does not arrive, then if GPs have pre-ordered the best vaccines for their patients for the next season, then at least next years’ flu defences could be ever so much stronger, and certainly better than those of our opening batsmen in Australia.