Are penguins sick of humans? It's more likely that they are sick because of humans. According to Australian scientists, emperor penguins have been infected by a poultry virus, which they reckon has been introduced by contact with people. Tougher environmental restrictions are now being prepared to prevent the Antarctic birds from getting infections passed on by humans. "It's highly likely that someone may have thrown away chicken remains, birds have eaten them and the virus has been passed on to penguins," said Stuart Prior, head of the New Zealand delegation at the 21st Antarctic Treaty meeting in Christchurch last week. "However, the Antarctic environment protocol, soon to be ratified, should reduce the risk of further infections being transmitted." The poultry virus causes serious disease in penguin chicks, increasing their susceptibility to other infections and reducing growth rates.

Hold your breath - there's a star heading right for us. Hipparcos, the orbiting space telescope (see story above) has found that one undistinguished star, languishing under the catalogue name Gliese 710, is coming straight at us. Currently 63 light years away, in 800,000 years - a mere eyeblink on the astronomical time scale - the star will pass us just half a light year away. That's only one-tenth the distance of the current nearest star, Alpha Centauri. As well as shining as bright as Venus in our skies, the wayward star may shake loose many of the small icy worlds from the outer solar system, sending them towards the Sun as comets.

Thalidomide is back in the news. In the 1950s it was notorious for causing birth defects when used by pregnant women to combat morning sickness. But now, doctors have found it can alleviate painful mouth and throat sores in people infected with HIV, according to a study in Thursday's New England Journal of Medicine. A double-blind study found that the drug completely healed the sores in 55 per cent of the thalidomide recipients, compared to 7 per cent among those taking a placebo. But there were side- effects, including a rise in the "viral load", a sign of progressing infection.

Food-related Escherichia coli infections, causing serious and potentially life-threatening illness, are on the rise, the World Health Organisation notes. The recently recognised E. coli O157 pathogen, already responsible for a multitude of deaths over the past few years, is likely to continue infecting people unless proper measures are taken. Experts from 14 countries agreed at a World Health Organisation meeting that even though E. coli is often linked to contaminated meat, a wider range of food may be responsible. Fresh vegetables "are becoming increasingly important as a source of food- borne transmission", noted one, saying that production and control guidelines are needed for ready-to-eat raw agricultural products.

The use of organophosphate dips for sheep could put their farmers at risk of weakened bones, an unpublished study suggests. According to New Scientist magazine, Anthony Lyons (of the Queen's Medical Centre, Nottingham) and Stephen Hodges (Northern General Hospital, Sheffield) studied eight farmers, whose average age was 49, and found signs of osteoporosis in half of them. A larger, controlled study with 150 people is now under way. The National Osteoporosis Society is backing the study, saying the initial findings "should be investigated".