The extent of influenza cases is unusual so early in the winter season, writes Dr Muiris Houston, Medical Correspondent
Confirmation that we may soon be in the grip of a major flu outbreak comes after two years of very low influenza activity in the Northern hemisphere. It is also unusually early in the flu season for the virus to take hold; the normal peak comes in January and February.
Influenza A, which is occurring at present, is one of three types of flu virus. A and B have the greatest impact on human health, with influenza A the type responsible for previous epidemics and pandemics. Type C is associated with sporadic and usually asymptomatic infection.
The current World Health Organisation recommended vaccine contains protection against influenza A. And while the virus is constantly changing, it would take a major shift in subtype for a pandemic to occur. The last pandemic occurred in 1977-78.
Nevertheless, we are likely to see a six- to eight-week period of 'flu activity as the virus spreads rapidly by droplet infection. Coughing and sneezing propels the virus from one person to the next. School-aged children play a big part in the transmission of 'flu in the community. A person will notice the first 'flu symptoms two days after being infected. Headache, aching muscles, chills, a fever and a general feeling of being unwell come on quite rapidly. Rapid onset as well as severity of the symptoms differentiate the 'flu from a regular cold. Symptoms last for three to five days, though a nagging cough and tiredness often persist for two weeks or so.
It is best to go to bed and rest, making sure to drink plenty of fluids. Paracetamol helps the aches and pains. The majority of people make a good recovery without the need for specific medical intervention.
Vaccination is recommended for people over 65, those with chronic health problems, such as heart disease and breathing difficulties, and for healthcare workers. It is not too late to be vaccinated, but if you are in a risk group do not delay; contact your GP today.