A telltale skin rash
US science website Nautilus, that on most surfaces the virus isn’t strong enough to make you ill. In her view, there is no need to worry much about the infectious potential of, say, touching a doorknob or a switch or a supermarket trolley. The fear about transmission from fomites – metal, plastic and other contaminated surfaces – is probably misplaced. “The surface issue has essentially gone away,” she says. Some of the basis for her claim rests on recent research done by the US microbiologist Prof Emanuel Goldman, who, having analysed several influential laboratory studies showing how the virus can linger on surfaces for hours and even days, found that the lab tests “bore little resemblance to real-life scenarios”. In those scenarios, risk of transmission from inanimate surfaces is very small: it only becomes a problem in instances where an infected person coughs or sneezes on the surface, and then someone else touches it within an hour or two. His findings were given further support by Italian research conducted by Mario Mondelli, professor of infectious diseases at the University of Pavia. He and his team attempted to grow the virus from samples taken from surfaces in a coronavirus hospital in Pavia, but were unsuccessful. However, regular handwashing is still seen as a sensible precaution.
Fever, a continuous cough and loss of the sense of taste or smell are three undisputed symptoms of Covid-19. Research led by Dr Mario Falchi at King’s College London indicates that a skin rash is too. The researchers, using the Covid Symptom Study app (which has been downloaded by more than four million people), found that 8.8% of their sample of 2,021 UK residents testing positive for Covid-19 had characteristic rashes or skin discolouration. He is urging the NHS to add “rash” to the three existing indicators.
When we gaze with affection on our pets, we like to think the feeling is reciprocated, but new research suggests dogs are actually not much good at recognising human faces. A team at Eötvös Loránd University, in Budapest, conducted MRI brain scans on 30 men and women and 20 dogs (all pets) as they were shown videos of dog and human faces. When the humans were shown the faces, the visual cortex in their brains burst into life; but the dogs’ brains displayed no more excitement on being shown the faces than when shown the back of people’s heads. “We found no dog brain regions which seemed to be tuned to care about faces,” researcher Attila Andics explained in The Journal of Neuroscience. For recognition purposes, the canine brain relies far more on the sense of smell (look how dogs sniff each other’s bottoms) and sound – though Andics thinks dogs do learn to care about their owners’ faces over time.
Cats, by contrast, do seem to respond to a human smile – not the usual kind however, but a so-called Duchenne smile (which involves the skin around the eyes crumpling into crow’s feet), accompanied by slow blinking of the eyes. After trials on a wide range of different cats, a team from the universities of Sussex and Portsmouth found that when given the Duchenne smile/slow blink treatment, the cats were much more likely to blink back at their owners or approach the outstretched hand of a stranger. “As someone who has both studied animal behaviour and is a cat owner, it’s great to show that cats and humans can communicate,” research supervisor, Prof Karen McComb, noted in Scientific Reports.