Influenza Vaccination 2018; Which vaccine is best? What about timing?

by Dr Bob Kass - April 10, 2018

Vaccination for seasonal influenza used to be very straightforward.

There was essentially one vaccine, a trivalent one comprising of 2 strains of influenza A and one of B. Its composition was usually decided in September the year before and the vaccine made available no earlier than April/May the following year. There would always be a quantity of government-funded vaccine for 2 particular groups; those over 65 years and those with risk factors for serious disease.

The same vaccine would also be provided in the private market at a reasonable cost to the consumer. In most situations the influenza vaccine was given in a medical practice where advice might be offered on other vaccine preventable disease (eg pneumonia, shingles and whooping cough) and perhaps a catch up on screening for other preventable disease eg bowel, breast. 

Influenza Vaccines Available in 2018

Let's fast forward to 2018 where we now have a number of different influenza vaccines available, recommended for different ages with slightly different compositions and strength. See Table 1 below:

types of flu vaccines available in Australia by age group in 2018

Today we have many different providers including medical clinics, pharmacies and corporate services all offering 'flu shots'.

We also now see mixed messages in the media with government and medical sources asking for a delay in giving the annual influenza vaccine, yet corporate groups already vaccinating organisations and pharmacies advertising flu vaccines for weeks.

Read more: ABC News - Hold off getting the flu vaccine 

At least no-one is saying a “killer flu” is either here or on the way. This is good as there is no evidence of increased influenza activity in the community and certainly not in South Australia (see below).

influenza cases in South Australia per week from 2016 to 2018

 

2017 Flu Season

Last year was NOT a good year for influenza in Australia. There were almost 250,000 laboratory notified cases. The previous 2 years were also significant with 91,000 in 2016 and 100,000 in 2015.  

These numbers are dramatically different to 2012/13 where notifications were much lower (44,000 and 28,000). It can’t be explained purely on better data collection because there is no doubt that last year was bad for flu and absenteeism was high. 

The end result is a lack of confidence in the value of influenza vaccination AND the system.

Timing of Flu Vaccinations

Changing the way we do things isn’t always for the better. Nor is “more” also better! We must now question the timing of flu vaccinations.

Corporate flu programs can be big business. Organisations and the public must consider the timing of vaccinations very carefully and the first in with the cheapest price might not be the best option.  

The timing of vaccination programs for nursing home residents is probably the most critical. There is considerable evidence to say that frail, elderly people with failing immunity may not hold their levels of protection if given the vaccine early.

This is certainly the case with Influenza A, H3N2 which was responsible for serious disease late in the season (September/ October) in 2017. The same problem was observed in the USA in the season just ending. Perhaps the impact of climate change is also being seen with seasonal influenza!

 

Note large spike in Australian laboratory confirmed annual flu numbers

Over 65?

In February, the Australian Technical Advisory Group on Immunisations (ATAGI) released a statement on the seasonal influenza vaccines for 2018. The following vaccines were recommended for use.

The enhanced trivalent vaccines for those over 65 years will contain the following strains:

  • A(H1N1): an A/Michigan/45/2015 (H1N1)pdm09-like virus
  • A(H3N2): an A/Singapore/INFIMH-16-0019/2016 (H3N2)-like virus
  • B: a B/Phuket/3073/2013-like virus

There are 2 different vaccines available. Fluzone  will contain 4 times the dose of each constituent strain and Fluad contains a specific adjuvant to enhance activity. Hopefully both will provide antibody levels sufficient to last the season. 

In 2017 there were more than 1000 influenza-related deaths in Australia. Over 90% were aged over 65 years.

It is important for those over the age of 65, who are still in the workforce, to consider opting out of their “free vaccine” at work or an early vaccination at a pharmacy and follow up with their medical practice to receive the recommended government-funded vaccine in May.

At the same time, you could seek information on the new bowel cancer detection kit. This is a major prevention initiative and when fully implemented by 2020, all Australians aged 50 to 74 with access to Medicare funded services will be offered a free bowel screening test every 2 years. 

Check your eligibility for a free bowel screening test here.

Further information on influenza vaccination may be found at Influenzacentre.org

 


Author

Dr Bob Kass

Dr Bob Kass is Medical Director of Globe Medical. He holds specialist qualifications in paediatrics and public health medicine and is one of Australia's pioneers in the discipline of Travel Medicine. 

Full professional biography | Book an Appointment with Dr Kass