Each year, experts from the US Food and Drug Administration, the World Health Organisation, the Centres for Disease Control and Prevention and other public health experts study global disease patterns and obtain and analyse influenza virus samples to identify the virus strains most likely to cause severe influenza during the upcoming flu season.

Influenza is a seasonal disease that is transmitted through the air by coughs or sneezes, through direct contact with bird droppings or nasal secretions or through contact with contaminated surfaces.

Vaccination remains the cornerstone of influenza prevention. Influenza is a contagious respiratory disease caused by a variety of different viruses that infect the nose, throat and lungs and then progress to the rest of the body, causing generalised disease with fever, a sore throat, muscle aches and pains, among other general discomfort. Nausea and vomiting is also a common feature in children.

Influenza is inactivated by sunlight, disinfectants and detergents, so frequent hand washing with soap or alcohol-based gel reduces the risk of infection. It is often confused with the common cold, which is grossly inaccurate as influenza is a far more severe disease and is caused by an altogether different type of virus.

Approximately 33 per cent of people with influenza have no symptoms but are natural carriers of the disease.

Flu may lead to pneumonia, either direct viral pneumonia or secondary bacterial pneumonia, even in healthy and young individuals, and this may require hospitalisation and could also lead to severe complications.

This year’s influenza vaccine will provide protection against the three influenza virus strains that global surveillance indicates are most likely to be the most common strains circulating this winter.

Naturally, despite the many millions of euros spent annually in preparing this vaccine, there is always the possibility of an imperfect match between the virus strains predicted to circulate and those that end up causing the most severe influenza illness. However, even in such cases, the vaccine is likely to offset and blunt the more severe symptoms and complications. It is especially important to get vaccinated this year because two of the three virus strains used in this season’s influenza vaccines differ from the strains included in last year’s.

According to the CDC, between five and 20 per cent of the population develops influenza each year. This leads to more than 200,000 hospitalisations in the United States alone from related complications and deaths estimated at 3,000 to 49,000 people.

The general advice of the health profession is that everyone who is six months of age and older should receive the annual influenza vaccine. The elderly and the very young (under fives) are most susceptible to contracting flu and it is therefore highly recommended for these groups and all those with chronic disease because these are likelier to have complications, such as pneumonia.

Healthcare providers play an important role in advising their patients to be vaccinated each year. Due to their exposure risk, they should also protect themselves, their patients, their family and the community in which they serve from influenza by getting vaccinated.

All the vaccines are extensively tested in terms of safety and effectiveness. Therefore, there is no reason whatsoever why people should harbour any thoughts about rumoured side effects.

The benefits of receiving the flu jab far outweigh potential disadvantages, especially for the vulnerable and the elderly, so people should not waste any time to ensure they are vaccinated against the very unpleasant, and, sometimes, life-threatening, onset of influenza.