Having a bad cold or the flu can significantly affect a driver's responses, reports BBC news. One hundred drivers with a range of conditions including colds, stress and headaches and 50 who were healthy were put through a hazard simulator test. The research, for Lloyds TSB Insurance, found that drivers with colds scored, on average, 11% worse - equivalent to the effect of a double whisky.

Experts said being ill could affect driving ability... The study, carried out by PCP research agency, looked at 60 people with colds and flu as well as 40 with other conditions including premenstrual syndrome.

They said that applying the 11% effect to reaction times, would add 1m to stopping distance if travelling at 48km/h - on top of a normal distance of 12m. It would add 2.3m onto the normal stopping distance of 96m, if travelling at 113km/h.

In a separate YouGov poll of 4,000 people, 22 people had had an accident while having a bad cold and five while they had flu.

The company estimated that, as 33.5 million adults drive in Britain, extrapolating out the YouGov figures would equate to 125,000 accidents caused last year by motorists with colds and flu.

It warned that being unwell at the wheel, particularly when combined with medication, fatigue or a small amount of alcohol, could all have a significant impact on driving ability....

BBC