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My wife is often bitten by spiders. Can anyone explain her allure for arachnids, and suggest how she might reduce it?

鈥� My sympathy to the correspondent鈥檚 wife, but any complaint of repeated spider bites is more or less certainly misdiagnosis. Spiders rarely bite, and only when people handle them roughly.

Unfortunately, people commonly reject suggestions that their symptoms, however genuine, have no connection with spiders. To compound the problem, medical staff with poor arachnid knowledge, or who lack the patience to argue, sometimes indulge the fiction, reinforcing the person鈥檚 readiness to attribute every localised idiopathic skin condition to spider bites.

The range of infections and injuries that people mistake for spider bites is startling: it includes trivial strep pustules, recurrent MRSA infections, mycobacterial abscesses, viral vesicles, chemical burns, allergic rashes and, of course, other kinds of bite 鈥� from mosquitoes, blackflies, bedbugs, fleas, lice, ticks or bloodsucking mites.

My neighbour recently complained of repeated bites from jumping spiders. Once he accurately described the bites, it was clear they were from our local .

People vary dramatically in their reactions to bites, and Ceratopogonidae are likely suspects for the bites incurred by your correspondent鈥檚 wife. As for the questioner鈥檚 apparent immunity, it might simply reflect a lack of reaction, if bites are in fact the cause.

Jon Richfield, Somerset West, South Africa

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