Are Influenza Vaccines Worth It?

This blog was based on the paper written by: Palache, Abraham. (2018). Internal Medicine Review. Global Seasonal Influenza Disease and Vaccination: A Paradox with Substantial Public Health Implications. To learn more, click here.

To the average person, the flu (also known as influenza), is no more than a severe form of the cold that causes inconvenience for a week or so.  However, many are not aware that influenza has a serious socio-economic burden due to absence from work and loss of productivity,¹ and can lead to complications or worsen existing illnesses, particularly for high-risk groups such as:

• Children under the age of 5
• Those with existing medical conditions
• Older adults²

Thankfully, a vaccine is available.  The influenza virus is unique as there are different strains that circulate, and new strains of the virus are constantly emerging, meaning the flu vaccine must be taken every year in order to be protected.

The World Health Organization recommends that those from high-risk groups receive their seasonal flu shot,³ however the process of annual re-vaccination is an obstacle to achieving high coverage rates. Additional factors that negatively impact vaccination rates include:

• Vaccine hesitancy
• Misinterpretation
• Inaccurate conclusions from local studies on the effectiveness of vaccines

Local studies are significantly impacted by many circumstances, such as the extent of the circulating virus, the immune status of the population before vaccination and how accurate the strains in the vaccine match the circulating influenza strains.  If these conditions are not accounted for, then the results will not be accurate or generalizable.

Health authorities usually rely on national data to implement healthy public policy.  Since many countries do not have sufficient influenza surveillance systems, this can impede prevention policies from being implemented.

As author Dr. Abraham Palache stated in his research publication, “This poses a huge public health dilemma, since national borders offer no defence to the threat of influenza.  Should vaccination be offered based on the global evidence and experience or not because of insufficient national surveillance infrastructure and therefore insufficient national data?”

Evidence for the global benefit of seasonal influenza vaccination has been collected over the past 50 years, demonstrating that influenza-related disease, hospitalization and deaths impact all populations globally.  Therefore, it is rational to assume that countries without an influenza monitoring system have a similar disease burden as countries in the same geographic region where more established monitoring exists.

It is therefore recommended to use the existing “global file on influenza vaccines” as the foundation for vaccination policies across the world, rather than relying on better local evidence.  The benefits would be immediate and every 3-5 years, updated global research could be used to inform any need for adaptation of the current global or national policies.

When global evidence supports the benefit of influenza vaccinations, failing to vaccinate risk groups, including older adults, would be against ethical and evidence-based medical practice.  In older persons, an influenza infection may result in loss of independence, aggravate underlying conditions and lead to complications such as pneumonia.

For the health and well-being of at-risk populations and the community at large, it is worth a shot. Pun intended.

References

[1] Gasparini R, Amicizia D, Lai PL, Panatto D. Clinical and socioeconomic impact of seasonal and pandemic influenza in adults and the elderly. Human Vaccines & Immunotherapeutics 2012; 8(1): 21-28.

[2] Monto AS, Ansaldi F, Aspinall R, McElhaney JE, Montaño LF, Nichol KL, Puig-Barberà J, Schmitt J, Stephenson I. Influenza control in the 21st century: Optimizing protection of older adults. Vaccine 2009; 27(37):5043-53. doi: 10.1016/j.vaccine.2009.06.032.

[3] WHO. Vaccines against influenza – WHO position paper – November 2012. Wkly Epidemiol Rec 2012 Nov 23; 87(47):461-76.