Introduction

Influenza is an acute viral infection that affects the upper or lower respiratory tract. It is characterized by fever, chills, and a widespread sense of weakness and discomfort in the muscles, as well as different degrees of headache and abdominal aches.¹ Although influenza can be dangerous for anyone, those 65 and older are at a higher risk of influenza-related complications and hospitalization. 

As people age, their immune systems weaken, making them more vulnerable to severe influenza and influenza-related complications such as pneumonia and hospitalization. Additionally, influenza increases the risk of heart attack by 3-5 times and stroke by 2-3 times in the first two weeks of illness for people 65 and older. This risk remains high for several months resulting in a a 6-fold increased risk of death from influenza and accompanying complications in this age group.²

Overview

The influenza virus is a member of the Orthomyxoviridae family, and there are three types: A, B, and C, with only the first two causing widespread outbreaks. All influenza viruses have segmented genomes, made up of eight single-stranded RNA segments, wrapped within a lipid envelope produced from the host cell membrane, and they exhibit high antigenic variation, primarily due to single but cumulative nucleotide alterations known as antigenic drift.

Mutation rates in RNA viruses, such as influenza and HIV, are substantially higher than in eukaryotes or DNA viruses, due to the absence of RNA repair mechanisms that exist for DNA replication.³ Recently, there have been a number of outbreaks of diverse types that, fortunately, have not spread from person to person. For example, from May 1997 to early 1998, there were 18 verified human instances of an H5N1 virus (identical to an avian variant that killed thousands of chickens), six of which were deadly.

Overall, since this chapter was created, the H5N1 virus has caused 79 human infections in Vietnam, Cambodia, and Thailand, 46 of which were fatal. It is clear that the world is in peril if these strains are able to spread from person to person. WHO reports have surfaced during the completion of this manuscript's final draft, suggesting that the pattern of avian flu illnesses in northern Vietnam now aligns with human-to-human transmission.

In the majority of non-pandemic years, influenza epidemics mostly strike temperate regions in the winter and are brought on by virus strains that have migrated from prior years' circulation. In the United States alone, these epidemics are typically to blame for over 36,000 additional deaths every year. People aged 65 or older account for 90% of these deaths, according to estimates.⁴

Complications 

Elderly people are more susceptible to complications from influenza. The most common, whether brought on by viruses or bacteria, is pneumonia. Within 24 hours of the commencement of influenza, usually, a Type A influenza infection, viral pneumonia, and toxaemia can occur. Because these patients have sensitive airways, inflammation brought on by the flu can exacerbate the symptoms of chronic obstructive pulmonary disease (COPD), trigger asthma attacks, and quickly result in pneumonia and other respiratory infections.⁶

FAQs

How effective is the influenza vaccine? 

Although it is not 100% effective, getting vaccinated against influenza is the best approach to avoid the discomfort and complications associated with the illness. For everyone six months of age or older, the Centres for Disease Control and Prevention (CDC) advises being vaccinated against influenza each year. The likelihood of contracting influenza may also be reduced by the flu vaccine. Additionally, it can decrease the likelihood of becoming seriously unwell from influenza, hospitalization, or death due to the illness.⁷

What can you do if you get influenza?

If you contract influenza, consult a healthcare provider about appropriate medications; antiviral drugs are often recommended. Ensure you get plenty of rest and avoid crowded places to minimize the spread of the virus. For elderly patients with a history of respiratory complications, it is recommended that they continue to monitor their condition so that unwanted complications do not occur, and immediately contact medical personnel if they experience excessive shortness of breath or other symptoms outside the general symptoms of influenza are detected.⁸

How to prevent Influenza? 

• Hand Hygiene: Spend at least 20 seconds washing your hands with soap and water. If water or soap is not available, sanitize your hands with an alcohol-based sanitizer
• Respiratory Etiquette: When you sneeze or cough, cover your mouth with your elbow or a tissue, and then thoroughly wash your hands
• Social Distancing: Avoid close contact with others in places like schools or public transportation, as influenza is easily spread in these settings

Summary

Influenza is a severe viral disease of the upper or lower respiratory tract that can lead to significant health issues, particularly for those aged 65 and older. These individuals are at a higher risk of complications and hospitalization. For elderly patients with disease complications, it is advisable to immediately consult medical personnel to obtain appropriate treatment so as to reduce the risk of complications with other diseases.