Researchers from Brazil have just reported that skin flakes in the hair of children with dandruff provide a comfortable refuge for house-dust mites, which trigger allergic responses that can cause asthma. Charles Naspitz and his colleagues from the paediatrics department of Federal University of Sao Paulo have collected through a hand-held vacuum cleaner material from the children's scalp just before they took a shower. They discovered two common species of dust mites Matophagoides pteronyssinus and Bloma tropicalis in the scalp of both asthmatic and non-asthmatic children. But the presence of antibodies to these mites in asthmatic children convinced the researchers to conclude that these agents trigger asthmatic attacks ( New Scientist , Vol 153, No 2069).