Flu Epidemics

Flu Epidemic

What is the flu?

The flu is a slang name for influenza, one of the oldest and most common diseases known. Influenza is an illness that affects the respiratory tract and related air passageways, and can produce many symptoms, including inflammation, coughing, sneezing, runny nose, fatigue, aches and shivers and in certain circumstances it can be fatal.

The flu actually kills hundreds of thousands of people every year, according to the World Health Organisation, which has been monitoring outbreaks of the disease for over fifty years. It is especially dangerous in winter months, as it is highly contagious. The congregation of people in close proximity indoors that occurs during cold weather can help the disease to spread rapidly in this part of the world.

What is a flu epidemic?

A flu epidemic is when the disease spreads rapidly through a population, causing many to be infected at the same time. An influenza epidemic can be a very costly business — the number of sick people off work can affect whole economies, while health services can be stretched to breaking by the volume of people seeking their assistance.

Though the flu breaks out in Ireland, and most other countries, every year, it is only every 10 or 15 years that a serious epidemic breaks out across a number of countries. Worse again is a pandemic, where much of the planet can be affected by a raging influenza epidemic. A flu pandemic was first described in Europe in 1580, and since then there have been over 30 flu pandemics, of which four occurred in the last century.

After World War One, 'Spanish' flu broke out in a pandemic across Europe and parts of Africa and Asia. It is estimated that 20 million died in this pandemic, more than died in the War itself. A flu pandemic occurs when humans do not have any immunity whatsoever to the disease. This tends to happen when a new variant of one of the flu viruses develops, often as a result of transmitting itself across species, from an animal to humans. The pandemics of 'Asian' flu in 1957, 'Hong Kong' flu in 1968 and 'Beijing' flu in 1997 all derived from avian (bird) illnesses, whereas it is thought that the 'Spanish' flu of 1918 was derived from a swine disease.

How come the flu spreads so quickly?

The flu is an airborne infection, which means that the viruses that cause the flu can live outside of the human body while seeking a new host to infect. Influenza infects the upper respiratory tract, leading to symptoms such as sore throats, runny noses, coughing and sneezing. The coughs and sneezes in particular are responsible for the spreading of the disease. If you inhale air containing particles from someone’s cough or sneeze, you are likely to become infected with influenza too.

Wintry weather makes it even easier for influenza to spread like wildfire among a population. Cold and wet weather drives people indoors, and large gatherings in crowded spaces are ideal breeding grounds for infections to spread. Crowded transport, shops, cafes and pubs are perfect locations for influenza to spread throughout the population.

Is there a cure for the flu?

There is no cure for influenza because the disease itself is constantly on the move. The viruses that are responsible for influenza are ever changing, which makes it impossible for the human body to develop antibodies to the illness. Each year, the current strain of flu must be identified and a new vaccine created to counteract the effect of the viruses.

Worldwide, the monitoring of influenza is co-ordinated by the World Health Organisation. Constant global surveillance of the disease is necessary to ensure that if a pandemic breaks out, there will be sufficient quantities of the right vaccine available. In Ireland, the monitoring of the disease is conducted by the National Disease Surveillance Centre, and the Virus Reference Laboratory, which is based in UCD, provides the essential analysis of the current strains of flu that allow a vaccine to be made.

What precautions can I take if there is a flu epidemic?

Certain people are more likely to suffer greatly if they contract influenza. The very young and old, and those with underlying illnesses, such as diabetes, or heart or circulation difficulties, are advised to get a vaccination against influenza every year. Your GP can arrange to give you a flu shot, which should offer protection against the disease for up to twelve months. It is a good idea to discuss the flu vaccine with your doctor in the autumn. The flu vaccine for the current year usually becomes available to doctors in September.

Influenza infection is generally so common during winter months that avoidance is nigh on impossible. Precautions, such as covering your nose and mouth in public, may help, but are not always practical. Receiving an influenza vaccination in autumn is the only method to avoid falling ill with the flu.

The flu vaccine does not prevent other coughs and colds which you may pick up during the winter.

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