Influenza Virus: The Evolution of a Deadly Virus in Our World

Sunday, 30 July 2017: 2:30 PM

Cathy M. St. Pierre, PhD
Specialty and Acute Care/VASH Program/ Research, ENRM VA Hospital, Bedford, MA, USA

Despite significant advances in health care today and the fact that influenza illness is a preventable disease, Influenza virus continues to be a significant cause of morbidity and mortality in the world. Influenza continues to rank in the top 10 causes of death in the world and infects up to 5 million people annually (WHO, 2014). The Influenza virus is compose of three types: A, B and C. Initially, Influenza virus A was thought to be only present in birds and poultry. However, in recent years, it has come to light that strains of the Influenza virus A, known as the Hemagglutinin proteins(HA) and Neuraminidase (NA) protein has infected humans (CDC,2015). Since that time, the HA,NA(known as H#,N#) strains have continued to mutate and it is now known that up that there are 18 subtypes of H proteins and 11 known subtypes of the N proteins (CDC, 2015). Because of the mutation of these influenza virus proteins over the past several years (2003-2015), mortality rates from influenza, in several countries has risen to greater than 50% (WHO, 2015). In 2012, the Global Influenza Initiative (GII) was created to establish the scientific evidence for the worldwide burden of disease attributable to Influenza virus (Paget, 2015).

 Generally, the “flu” infects up to 20% of the general population and will result in over 500,000 deaths each year. Unfortunately, some of our most vulnerable populations: infants, pregnant females and the elderly, are at greatest risk for contracting this disease (Cheng et al, 2015). For example, In 2010, 90% of the influenza deaths that occurred in the USA, were in the elderly population (Heron, 2013). This is despite the fact that the elderly population as a whole, represent the highest compliance rates for immunization (65%).

This presentation will focus on the evolution of influenza viruses throughout the world and the current strategies in place to monitor disease incidence, prevalence and current recommendations for prevention and treatment of both the general and at risk populations. The new quadrivalent and high-dose vaccines will also be discussed as well as policies related to the risk, benefits and effectiveness of these vaccines. (Demicheli et al, 2014).