Insect repellents and insecticides may cause Gulf War Syndrome when used together, according to researchers in the United States. They tested a combination of DEET (the leading mosquito repellent for travellers) and Permethrin (an ingredient in fly sprays). The report says a combination of the two drugs can lead to weight loss, diarrhoea and leg weakness. The Medical Advisory Service for Travellers Abroad says exposure should be reduced, for example by using a repellent based on extract of lemon eucalyptus. Call MASTA on 0891 224100, a premium-rate service, for a Health Brief.

Visit Latin America in London WC2 this summer. At the City Lit Institute (0171-403 0201), the Latin America Bureau is running day schools on topics such as the search for El Dorado (8 June) and "Cuba: Paradise Lost?" (22 June). Each costs pounds 17.50.