TROPICAL MEDICINE

Tropical Climate

In the tropical regions two types of climate can be expected; these are:

• Dry desert climate with very high day temperatures and very cold nights;
• Hot, humid climate with high temperatures and humidity around 90% during the day and at night.

The hot and humid conditions can be extremely tiring and tend to reduce working intensity.

If one perspires a lot, the intake of liquid and salt should be increased. It is important to protect oneself from ultraviolet radiation of the sun. This radiation can cause sunburn or snow blindness.

To protect oneself against ultraviolet radiation, it is best to limit sunbathing to short periods and to use sun block, lotions and reliable sunglasses. Intake of alcohol should be restricted as it may add to dehydration. Taking rest during midday is recommended.

Hygiene

Particular care should be taken regarding hygiene in tropical regions.
• Drinking Water: Supply of pure drinking water is the exception in tropical and subtropical areas. Water from the tap must be regarded as infected, even when it is merely used for brushing the teeth. As a guiding principle, do not drink any water that is not purified by boiling or by chemical disinfecting (chlorinating). The common infections acquired through contaminated water are typhoid fever, paratyphoid fever, and dysentery.

• Milk: Unboiled milk can be a source of infection.
• Recommended drinks: Boiled drinks and beverages in bottles. Make sure the bottles are opened in your presence.
• Ice: Ice is very often contaminated. Do not use ice in your drink.
• Fruit: Avoid eating raw fruit without peel. Only eat fruit that can be peeled. Safe types of fruit include oranges, bananas, mangoes, pineapples… etc., and always wash fruit before peeling. Wash grapes before eating.
• Salads and Raw Vegetables: Eating salads or raw vegetables increases the risk of worm infestation or of contracting amoebic dysentery if not thoroughly cleaned.
• Meats: Eat only fresh meat that has been freshly cooked. Avoid raw or cold meats.
• Fish: Eat only freshly cooked fish. Avoid shellfish (especially oysters).
• Bathing: Use only purified pools or open sea. Fungal diseases are common in hot humid climates. When bathing, it is advisable to plug your ears with cotton wool to prevent fungal infection of ear canal. Also wear shoes at poolside to avoid fungal infection of feet.

Tropical Diseases

Tropical diseases are not confined entirely to the tropics but can occur almost anywhere.

However their incidence and frequency are influenced by local factors. Tropical diseases are mainly transmitted through insect stings or bites, through healthy skin by other parasites, through food and drink, from the ground or person to person.

The following insects most commonly transmit diseases in tropical climates:

• Mosquitoes: transmit Malaria, Yellow Fever, Dengue Fever and Sandfly Fever;
• Tsetse Fly (Central Africa): transmit Sleeping Sickness;
• Lice: transmit Typhus, Relapsing Fever, Spotted Fever;
• Rat Fleas: transmit Plague.

Protective measures against insects

Sleeping quarters should be free of insects. Use mosquito nets over beds. Nets should be taut and should not come in contact with body. Protect the skin by using an insect repellent.

Diseases than are contracted through the skin:

• Bilharzia: Aquatic snails act as intermediaries. The larvae of worms pass from such snails into the water and on contact with the skin into the human body.
• Weil's Disease: The germs of this disease are excreted in rat's urine. They can penetrate the skin of bathers.
• Fungus Diseases: The fungus is present in tropical and sub-tropical inland waters, in shallow rivers and lakes, hardly ever in seawater.

Protective measures to avoid contagion through the skin:

Avoid inland water. Bathe only in pools with purified water or in the sea. Use cotton wool earplugs. Wear slippers when walking around the pool.