London - Flu can be spread long before symptoms appear, a study has found – leading to calls for widespread vaccination.
Doctors and nurses could unwittingly be infecting patients after being exposed to the bug, even if they feel perfectly healthy.
And office workers could be passing flu to colleagues before they have so much as coughed or sneezed.
Britain’s leading flu expert, Professor John Oxford of the Queen Mary School of Medicine in London, said the findings back the case for more healthcare workers to be given the flu jab – and even for a universal vaccination programme.
Although flu is easily shaken off by most, it typically claims 12,000 lives a year in the UK. Vulnerable groups, such as the elderly and pregnant, are entitled to free jabs, but most of the population is not vaccinated.
Research at Imperial College London showed that ferrets were capable of passing on flu 24 hours after being infected with the virus – even though they did not show symptoms for almost another full day.
Surprisingly, the virus appeared to be passed on more easily at this stage than when coughing and sneezing was at its height. Ferrets have been used in flu research for decades because they are susceptible to the same strains as humans and display similar symptoms.
Researcher Dr Kim Roberts said: ‘We continuously monitored the body temperature of the ferrets. They had a fever at 45 hours after infection. We also observed the ferrets to see when they were sneezing and coughing, and sneezing started at 48 hours after infection.’
However, the animals passed on the bug after just 24 hours, the journal PLoS ONE reports. It thought it was spread by viral particles expelled simply through breathing. - Daily Mail