Bites by dogs are common in all parts of the world. They may cause mechanical damage, including soft tissue injury, avulsion of nerves and tendons, compound fractures, and, rarely, death. They may also be complicated by a range of bacterial infections including tetanus. Some infections are peculiar to animal bites (eg Pasteurella multocida and rabies).

Bites may also be inflicted by domestic cats and monkeys, and less commonly by horses, rodents, bats and even large carnivores.

Infection may occasionally be introduced through scratches and licks over broken skin.

12.1.1  Treatment

Animal bites should not be ignored. Travellers should be advised to:

•   clean the wound thoroughly as soon as possible with soap/detergent and water (preferably under a running tap)

•   apply an antiseptic such as iodine or 40-70 per cent alcohol (gin, whisky and vodka contain about 40 per cent)

•   seek medical attention, preferably within 24 hours

•   medical attention may include wound toilet, antimicrobial therapy, immunisation with tetanus toxoid and, if the bite occurred in a rabies endemic area, rabies post-exposure prophylaxis (whether or not pre-exposure prophylaxis was given).

12.2   Snake bites

Dangerous species of snakes are found in many tropical countries and local inhabitants are not infrequently bitten and even killed. Foreign travellers are rarely bitten.

12.2.1  Prevention

Snakes do not attack humans without provocation; they should never be disturbed, cornered, attacked or handled even if they are said to be harmless or appear to be dead. Walking barefoot in vegetation, swimming in murky estuaries or rivers matted with vegetation, and climbing trees or rocks covered with foliage are all risky. A light should be used at night.

12.2.2  Treatment

Travellers can be advised about first-aid measures:

•   avoid tampering with the wound in any way

•   immobilise the bitten limb with a splint or sling

•   remove rings from a bitten hand

•   transport the victim to a dispensary, health clinic or hospital as quickly as possible for immediate attention

Medical or hospital treatment will be assisted if a description of the snake is available. Antivenom treatment should only be administered by those experienced in its use.

12.3  Bites and stings by marine animals

Coelenterate (eg jellyfish, Portuguese man-o-war) stings can be inactivated with dilute acetic acid, eg vinegar, or sometimes baking soda. Adherent tentacles should be removed carefully (not with bare hands).

The excruciating pain of stinging fish (weevers, scorpionfish, stonefish, stingrays) may be relieved by immersing the limb in water at a temperature of about 45ºC.

Sea urchin (Echinoderm) spines that get imbedded in the foot should be removed surgically after softening the skin with salicylic acid.

12.4  Hymenoptera stings (bees, wasps, hornets, ants)

People with known allergies to insect stings should carry emergency treatment (self-injectable 0.1 per cent adrenaline) and know how to use it. Even in a non-sensitised person, hundreds of stings by bees or wasps can be fatal through direct toxicity.

12.5  Scorpion stings and spider bites

The sting of most species of scorpion is painful. Some species in Mexico, North Africa, the Middle East, Latin America and India can cause myocardial damage and pancreatitis. Immediate medical help should be sought.

Very few species of spider are able to inject venom through human skin. Of those that can, a few species in South America and Australia cause neurotoxicity requiring specific antivenom treatment.

Spiders and scorpions may lurk in shoes and clothing, which should be checked before putting them on.

12.6  Leeches

Leeches are found in damp tropical forests and undergrowth. Wearing long socks, long trousers and boots liberally treated with repellants such as diethyltolumide helps to prevent them attaching to skin.