Worms may enter your body through skin (especially the soles of your feet), or food. An itchy anus is a common symptom, and you may even see them in your stools. They are easy to treat: if you suspect you have them, get some worming tablets such as Mebendazole (Vermox) from any pharmacy.

 

Biting insects and similar animals other than mosquitoes may also aggravate you. The obvious suspects are bed bugs - look for signs of squashed ones around cheap hotel beds. An infested mattress can be left in the hot sun all day to get rid of them, but they often live in the frame or even in walls or floors. Head and body lice can also be a nuisance, but medicated soap and shampoo (preferably brought with you from home) usually see them off. Avoid scratching bites, which can lead to infection. Bites from ticks and lice can spread typhus, characterized by fever, muscle aches, headaches, and, later, red eyes and a measles-like rash. If you think you have it, seek treatment (tetracycline is usually prescribed).

Snakes are unlikely to bite unless accidentally disturbed, and most are harmless in any case. To see one at all, you need to search stealthily - walk heavily and they usually oblige by disappearing. If you do get bitten, remember what the snake looked like (kill it if you can), try not to move the affected part, and seek medical help: anti-venoms are available in most hospitals. A few spiders have poisonous bites too. Remove leeches , which may attach themselves to you in jungle areas, with salt or a lit cigarette: never just pull them off.