Don’t let too much sun and biting insets ruin your vacation. Information and tips from the travel clinic at the Institute of Tropical Medicine.
Sunbathing can be good and will boost your vitamin D production. However, it is wise to sunbathe in moderation, in order to combat the accelerated ageing and skin cancer caused by sunburn.
UV radiation increases in intensity the closer you get to the equator. “In the tropics, it is best to use a sun care product with a protection factor of at least SPF30”, according to Professor Fons Van Gompel, head physician at the travel clinic at the Institute of Tropical Medicine. “You should definitely opt for an extra high protection factor if you need to use insect repellents that contain DEET simultaneously. DEET can reduce the efficacy of sun care products. Apply sun care products every two hours and after every swim. Be careful, as refreshing water does not reduce the risk of sunstroke. Spend plenty of time in the shade. This also helps to combat a lesser known problem: in warm and humid regions, it is easier for your sweat glands to become clogged and this can result in prickly heat rash, which causes an intense itching skin rash. These are fine, red spots that occur primarily on the shoulders and can occur all over the body in children. Cold showers, menthol talcum powder and cooling lotions that soothe the itching can offer relief.”
When thinking of animal pests to the skin, travellers often think of spiders, snakes and scorpions. However, there are very few incidents involving these animals. “On the other hand, people often underestimate the potential danger of more cuddly animals such as stray dogs and cats and tamed wild animals”, notes Van Gompel. “In many countries, animals can carry the rabies virus that is lethal to humans. It is not always easy to recognise animals that are sick. They may look rabid, but could also be weak or paralysed. If you are bitten, wash the wound with soap and water for 15 minutes. The virus is highly sensitive to detergents. Rinse the wound thoroughly and then disinfect. Consult a doctor immediately to determine whether you need to be given antibodies and the rabies vaccine. Travellers to developing countries who are planning a long cycle trip or go jogging often would be better off obtaining a preventative vaccination. This will offer them partial protection against the virus.”
However, unsightly small culprits are much more likely to cause discomfort due to bites during a vacation. Warm and humid regions have an enormous variety of insects. Their bites and stings can irritate the skin severely. If it itches… do not scratch, as this could lead to the wounds becoming infected. “Wound infections are often underestimated”, says Van Gompel. “Avoid scratching by calming the itch with a powerful cortisone cream. Often only one application of such a cream will do the trick. Avoid the facial area as much as possible and only apply in the evenings, due to the risk of photo-allergic reactions.”
The more time you spend in an area, the more likely it is that your skin will respond less severely to insect attacks. However, it remains important to protect yourself against bites. This is because some insects can cause diseases in certain areas.
The most well-known example of the feared mosquitoes is probably the Anopheles mosquito, which is infected with the malaria parasite in many (sub) tropical regions. This mosquito strikes almost exclusively between sundown and sunrise. “Several people from Belgium still die of malaria every year, because they did not take their anti-malaria medication or did not take it properly, or because they were misled by the first common symptoms and sought medical assistance only when it was too late. Therefore, the advice is: have your blood tested if you experience a fever whilst abroad or within 3 months of returning home. Even if you took your medication properly, as it does not offer 100 % protection! This is why general anti-mosquito measures (see reference box) remain essential during your trip.”
Another infamous type of mosquito is the Aedes species, which stings primarily during the day and – in South America and Africa – can transmit a virus that causes yellow fever. There is no cure for this infection with flu-like symptoms and it can even be fatal, though there is a very effective vaccine. If you are travelling to high-risk areas, then you must be able to present the “yellow booklet” as proof of vaccination. “People who cannot be vaccinated, for example due to decreased immunity, must implement very strict anti-mosquito measures during the day”, urges Van Gompel.
The Aedes mosquitoes also transmit dengue fever and chikungunya. These very similar viral infectious diseases are usually associated with fever and severe muscle aches (dengue) or joint inflammation (chikungunya). There is no cure, only symptomatic relief. As there is no vaccine yet, the only prevention strategy is to take anti-mosquito measures. “Dengue is expanding rapidly in many tropical areas”, says Van Gompel. “The chikungunya virus is currently causing epidemics in India and South (East) Asia. It also occurs sporadically in large parts of Africa and was also observed in the Caribbean in 2014, from where it will spread across Latin America over the coming years.”
One final example of mosquito problems? “Culex mosquitoes, which bite at night, can transmit Japanese encephalitis in Asia. As a tourist you will not be at high risk, unless you stay with rural locals, as pigs serves as a “reservoir” for the virus and rice paddies form ideal breeding grounds for mosquitoes. In that case, it would be best to vaccinate in advance.”
Football fans who wish to explore rural areas of Brazil or other Latin American countries after the World Cup should be wary of large blood-sucking insects of the genus Triatoma. Van Gompel explains that “the faeces that they release during their painless – usually nocturnal – bite can easily enter the bite wound and can contain a parasite”. “This may result in Chagas disease, which can damage the heart and other organs. Therefore, avoid sleeping in the open air or in primitive dwellings. If you opt for a cheap hotel, sleep under a mosquito net, preferably with another sheet spread over this to keep the bugs’ faeces out. Spray hiding places – such as behind frames, in drawers and under the matrass – with an insecticide. And apply an insect repellent to exposed skin.”
The African tsetse fly is not a fly that you can simply shoo away and insect repellents also have very little effect on these bothersome, large stinging flies. The fly can be infected with a parasite that causes the infamous sleeping sickness in humans. “However, the risk is very limited in tourist areas”, says Van Gompel. “Except in certain game reserves, such as the Serengeti and Tarangire parks in Tanzania. These are best explored in vehicles with the windows closed.”
Other African flies cause problems by dropping their eggs in washing that has been hung out to dry. “Destroy them by ironing the washing at a high temperature”, advises Van Gompel. “These fly larvae can penetrate your skin and develop there. The injury looks like a boil, but causes more itching than pain and has two central black dots, the breathing holes for the culprit.”
The injury caused by a chigoe flea is also sometimes confused with a boil, but it has one central black dot. “A fertilised chigoe flea can burrow into the upper layer of skin on the feet or under the toenails. She will remain there to grow, which causes the host itching and pain. You can remove these fleas by carefully removing the top layer of the skin with a needle. Remember to disinfect the wound afterwards!”
In addition to the chigoe flea, other parasites from dogs or cats can also nestle in your skin. For example, mud that has been contaminated with faeces is a possible source of infection for Old World hookworm larvae. If they enter the skin of an accidental human host they will usually die. However, they can travel through your skin for months, at a maximum speed of a few millimetres per day and cause a very itchy, twisting, line-shaped skin rash. Preferential sites include the feet, hands and buttocks. You can limit the risk of this typical tropical skin parasitosis by not walking around barefoot and always sitting on a beach towel.”
Insects can threaten the skin during vacations closer to home too. For example, for the Spanish fly you do not need to travel further than Southern Europe. The name is misleading, as it is in fact a blister beetle that is attracted to lights at night. There are many varieties in (sub) tropical regions. If you squash one of these bugs on your skin it will result in the release of irritating substances that cause red, swollen, burning injuries and blisters. “Disinfect the injury and treat it with a burn ointment”, advises Van Gompel.
Ticks can also be found close to home, particularly in rural and forested areas. Don’t be fooled into feeling safe whilst wearing concealing clothing and insect repellents. Always inspect your body after a nature walk. You can reduce the risk of ticks transmitting pathogens significantly by removing them from your skin quickly. “Except if the tick carries the Frühsommer Meningo-Enzephalitis virus, which occurs primarily in Central and Eastern Europe”, notes Van Gompel. “The FSME virus can be transmitted by the tick immediately after the bite. This is why the Austrian government warns tourists about this disease specifically. A warning is justified, but there is no reason to panic. The risk of an infected bite is very low and the infection is usually very mild, usually resulting in nothing more than flu-like symptoms. In very rare cases it can result in inflammation of the brain and meninges, but even then the disease usually passes without permanent damage. If you are trekking or camping in a high-risk area, you might consider having yourself vaccinated against this tick encephalitis.”
By An Swerts – Article Bodytalk 18/06/2014