Guests: Jo Brand, Ben Goldacre, Andy Hamilton
Aired: 4th November 2011, BBC Two
Zoonosis is illness caused by an animal; sleeping with, kissing, and being licked by your pet can make you ill.
Since 1974, multiple cases of plague have been linked to people in the south-western USA sleeping with flea-infested cats. In a 2008 outbreak, a study also found that people infected with bubonic plague were more likely to share a bed with a dog than uninfected people. Dogs are the more worrisome carriers as they show fewer symptoms than cats.
Surveys conducted in the USA, the United Kingdom, France and the Netherlands, suggest that between 14% and 45% of dogs sleep on or in an owner's bed, while 45-62% of cats sleep on or in the bed. Women were more likely than men to report sleeping regularly with dogs. The illnesses may be transmitted by the pets licking hands, faces, or wounds, and the people most at risk are young children and those with compromised immune systems. As well as the plague, you might
catch illnesses including MRSA and Pasteurellosis, or parasites such as hookworms or roundworms.
Researchers recommend that people avoid sharing their bed with a pet, or regularly kissing the animal. Any area licked by a pet — especially if it is an open wound or on a vulnerable person — should be washed immediately with soap and water, and pets should be kept free of fleas, dewormed and taken to regular veterinary visits.
The temperature of the water you wash your hands with has very little effect on the number of bacteria removed. To have an effect the water would have to be so hot that it would scald you.
In 1938, Dr P.B. Price published his summary of 80 studies that he had carried out over a nine-year period. He studied hand washing at temperatures ranging from 24°C up to 56°C. He found that the temperature made no real difference and that the most significant factor in removing germs was how vigorously the subjects scrubbed their hands. These findings were confirmed in a 2002 study by Dr Barry Michaels, in which volunteers' hands were deliberately soiled with ground beef contaminated with E. coli bacteria. They were then washed with soap and water at five different temperatures ranging from a chilly 4.4°C, to an uncomfortable 48.9°C. The temperatures made no real difference in the numbers of bacteria left on the skin, whether they were permanent resident bacteria, or transient immigrant bacteria. Just as Price found, it was the vigour of scrubbing that made
the difference. The temperature needed to kill bacteria on your hands would be over 80°C.
According to a study by the Maryland Health Council 90% of healthcare staff wash their hands when being watched, compared to 40% when they weren't.
In the 19th century, Ignaz Semmelweiss demonstrated that mortality due to puerperal fever could be reduced from 18% to 2% if doctors washed their hands, but he was tragically ignored.
Never tell people you are ill; never own it to yourself. Illness is one of those things which a man should resist on principle.
Quit worrying about your health. It'll go away.