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A 24-year study from Harvard University, found that twins were likely to suffer similar illnesses, suggesting that DNA drives 40 per cent of diseases.
Respiratory diseases expert Professor Ron Eccles, who heads the Common Cold Centre at Cardiff University, is convinced that genetics are the reason some people never catch the cold virus. He says: ‘We are each born with a unique immune system, akin to a fingerprint. Those who don’t suffer colds are probably infected with the virus, but their immune system kills it so they don’t develop symptoms.’
Common cold viruses primarily target the lining of the nose, the throat, larynx – or voice box – and sinuses.University of Sussex immunologist Dr Jenna Macciochi says: ‘There are more than 160 different cold variants and new ones appearing all the time, so it’s entirely reasonable for the average person to get one or two colds a year.
‘When a virus enters our airways, the delicate respiratory tract is attacked by it, resulting in a bunged up nose, sneezing, coughing and a sore throat.’ Dr Macciochi agrees that there are those who, for genetic reasons, are able to fight off colds better than others. But could the rest of us do something to protect ourselves?
Immune system relies on sleep to generate a robust number of healthy immune cells and weed out cells that are getting old and potentially dysfunctional,’ Smokers and those who drink alcohol regularly will increase their risk. Alcohol is a known sleep-disturbing factor, while smoking affects the cells of the lungs which are targeted by cold and flu viruses.