London - Are you wary of giving your partner a kiss for fear of catching their cold? If so, don’t be. Swapping saliva won’t pass on the cold virus, it was reported last week.
However, holding hands will - because your loved one is more likely to be harbouring the virus on their fingers from holding dirty hankies or coughing or sneezing into their hands, says Professor Ron Eccles, director of the Common Cold Centre at Cardiff University.
So, how do viruses and illnesses transfer from person to person, and how can you protect yourself? We asked the experts.
WHY MEASLES SPREAD SO QUICKLY
Diseases can spread through touching another person or an object contaminated with germs from someone else, or through the air, for example, when someone sneezes and the droplets enter your nose or mouth or get on to your hands.
A disease’s contagiousness is measured by its basic reproduction number. ‘This is the number of people without immunity who would likely be infected by one person with the virus,’ says Paul Griffiths, professor of virology at University College London.
‘One of the worst viruses for that is measles, with a basic reproduction number of 17. It’s airborne and really contagious.
‘We’ve seen recent outbreaks of it, for example, in Disneyland - standing in a queue next to someone with measles would be enough to catch it.
‘That’s why it’s so important for parents to keep up with their children’s jabs.’
Rhinovirus, the virus causing the common cold, has a basic reproduction number of six; norovirus is two and the flu virus is two to three.
With colds, the symptoms can last longer than the virus, says Professor Griffiths.
‘You’re infectious only when the virus is present, which is at the start of the illness,’ he says.
FLUSH THE LOO WITH THE LID DOWN
A simple way to protect yourself and your family against vomiting bugs such as norovirus is to get everyone in the habit of putting the lid down before flushing.
This stops germs in the bowl being projected in a plume as high as 6 ft, and landing on objects - and people - in the bathroom.
‘I have seen experiments in which fluorescent dyes have been put down toilets - when the chain was flushed, you can see how far materials from the bowl can travel through the air,’ says Mark Fielder, professor of medical microbiology at Kingston University.
‘This material may potentially contain bacteria and viruses such as norovirus that could be spread to other parts of the room.’
You should also ensure toothbrushes are kept far away from the loo so they’re not in the line of fire of cascading germs when the loo is flushed. This way you won’t take in germs through the mouth when you brush your teeth.
VIRUSES MAKE YOU FAT
A growing body of research suggests that some everyday viruses may trigger more serious and long-term health issues than just a cold or flu.
For instance, scientists believe that a common microbe, called adenovirus-36 or AD36, which causes a range of respiratory infections and cold symptoms, can also trigger significant weight gain in genetically pre-disposed people.
In a range of studies published in the International Journal of Obesity, Dr Richard Atkinson, a nutritional scientist at the University of Wisconsin, has found that 30 per cent of obese people have antibodies against AD36 - which shows that they have been previously infected with the virus - compared with just 10 per cent of people of normal weight. One theory is the virus may change the way the cells store fat.
Dr Atkinson, who is developing a vaccine against AD36, says: ‘Infection with this virus does not make people feel very ill, so if you are exposed to it you aren’t likely to know you’ve had it unless you get tested. But a test will alert you that you are going to have to be more careful than the average person to prevent weight gain.’
KISS CHILDREN ON TOP OF THE HEAD
During pregnancy, a woman’s immune system is lowered and so it’s important that she practises good hygiene and washes her hands regularly.
One little known, but common, problem is cytomegalovirus or CMV, which is present in two-thirds of women.
‘It doesn’t cause symptoms in the mother, but it can damage the hearing of the baby,’ says Professor Griffiths. ‘It’s the most common cause of hearing loss in children in the country - and it can damage intellectual potential, too.’
Around 60 per cent of women have had the CMV infection, but of the 40 per cent who haven’t, 2 per cent will acquire it during pregnancy. It’s this group - who catch it for the first time when expecting or who are reinfected with a new strain - that are most likely to pass it on to their unborn child with potential consequences on their health.
The virus can be passed via body fluids such as mucus, urine and saliva - pregnant women can catch it from kissing and cuddling children.
Children are likely to carry bugs because their immune systems are developing, so they are a common source of illness for adults.
‘The best defence is washing your hands regularly, especially after changing nappies,’ says Professor Griffiths. ‘You can’t put on a space suit - but you can kiss your child in a way that reduces the chance of exchanging saliva, such as on the top of the head.’
WEAR SOCKS TO STOP A COLD
Another reason to love your comfy slippers: if your toes are toasty, you may be better protected against coughs and colds.
When the feet get cold, the blood vessels constrict as a protective reflex to slow down the loss of heat from the body, says Professor Ron Eccles.
This happens in the nose, too, and as this is the main way for the cold virus to enter the body, this lowers the body’s defences.
‘It means there are fewer white blood cells in the nose to fight the virus,’ says Professor Eccles.
In experiments at the Common Cold Centre, volunteers who placed their feet in buckets of iced water for 20 minutes were more vulnerable to the cold virus afterwards.
A third of them got colds over the following five days, compared with 9 per cent in a group who kept their feet at normal temperature. Even if your feet are protected, it pays to wear a scarf to keep your nose warm when you go out on a chilly day.
‘Respiratory viruses prefer cold environments, so by putting a scarf over your nose you may be helping to reduce replication of viruses in the nose,’ says Dr Lisa Ackerley, visiting professor of environmental health at the University of Salford.
PUT PYJAMAS IN A HOT WASH
These days, we are encouraged to do laundry at lower temperatures on the grounds that it saves electricity.
But what may be good for the environment may not necessarily be good for your health, says Professor Sally Bloomfield, chair of the International Scientific Forum on Home Hygiene.
‘Clothing, such as pyjamas, underclothes, vests, pants and socks, come into close contact with our bodies and can gradually pick up organisms shed from the skin surface or from our bowels,’ says Professor Bloomfield, who is based at the London School of Hygiene and Tropical Medicine.
‘The longer we wear them, the more the microbes build up on our clothes. The same goes for towels and face cloths. If we wash these items at low temperatures with other people’s clothing, microbes can transfer from one item to another.’
Most of these organisms are harmless, but some can cause infections.
‘About one in three people carry staphylococcus aureus on their skin, which can cause infection if they get into cuts and grazes,’ she says.
‘We need better data, but based on what we know, we recommend pyjamas, underwear and towels should be laundered at 60c or above, or at 40c with a tablet or powder that contains active oxygen bleach.’
AVOID STAYING UP TOO LATE
Apart from washing your hands with soap and warm water regularly, getting plenty of sleep is another precaution you can take against cold and flu infections.
In a 2009 study published in the Archives of Internal Medicine, researchers infected 153 healthy men and women with cold viruses.
They found that the volunteers who slept less than seven to eight hours a night were three times more likely to get a cold than those who had a longer night’s sleep.
‘Regular sleep habits may play an important role in your immune system’s ability to fight off infectious disease,’ says Dr Sheldon Cohen, a psychologist at the Carnegie Mellon University in the U.S., who carried out the research.
Another study published in the journal Sleep in 2012 found that when 15 healthy men were kept awake for 29 hours, the rhythm of their white blood cells was disrupted, suggesting a weakening of the immune system.
COPPER TAPS STOP BUGS SPREADING
Copper taps, door handles and kitchen worktops may be the latest trend in interior design, but they can have a health benefit, too. The metal deactivates bacteria and viruses by killing their genetic material and suffocating them.
‘Copper surfaces can disrupt the cycle of germs replicating and lower the risk of outbreaks,’ says Professor Bill Keevil, director of the environmental healthcare unit at Southampton University.
‘We have found that the metal destroys the genetic material of the norovirus.’
WHAT YOU REALLY NEED IS A BIG HUG!
You don’t always need to rush off to the chemist for a remedy, happiness and hugs can also fight off the cold virus, says Dr Cohen.
In one trial, researchers squirted the cold virus up the nose of 334 healthy volunteers over two weeks and asked how happy they felt.
Feeling more positive was linked to a greater ability to fight off a cold.
In a further study published this month in the journal Psychological Science, Dr Cohen found that people who reported having regular hugs over the past two weeks were less likely to catch a cold. He said hugs, and feeling supported by others, reduces stress, which in turn protects immunity.
Daily Mail