Travel medicine: protection against ticks, mosquitoes and jellyfish

Infectious tropical diseases could spread to Switzerland as a result of climate change, as the warmer temperatures create an attractive habitat for disease carriers. Jan Fehr is Professor of Internal Medicine and Infectious Diseases at the University of Zurich and also works at the University’s Travel Clinic. Here, he explains the impact of climate change on tropical diseases in Switzerland and neighbouring countries. He also has a few tips on how to protect yourself against infection.

Ticks

Meningitis and tick-borne encephalitis (TBE) have increased significantly in recent years. Today, Switzerland is one of the countries in Europe most affected by the viral disease TBE. Ticks can also transmit bacterial diseases, such as Lyme disease. Both illnesses usually start with flu-like symptoms. In the early stages, Lyme disease can also lead to changes in the skin, which resemble a target. While Lyme disease can be treated with antibiotics, there is no cure for TBE. Treatment only relieves the symptoms.

There are several reasons for the increase in cases:

• Rising average temperatures: winters are milder, so ticks are active all year round. In addition, their habitat is expanding because the temperature is also rising in the mountains.

• More outdoor leisure activities: this puts people at risk of being bitten by ticks.

• Rapid reproduction: there are currently no measures in place to curb the spread of ticks.

Mosquitoes

The origins of tropical diseases in Europe can be traced back to the Age of Discovery, when commercial travellers from faraway countries often brought with them more than just goods. Malaria is a good example of this. This disease, transmitted by a specific mosquito species, was introduced by infected mosquitoes along trade routes. In antiquity, malaria was particularly common in the swamps of southern Europe. The control measures in the 19th and 20th centuries proved successful and the number of cases fell sharply in the middle of the 20th century. Several countries in southern Europe have been declared malaria-free. However, consistently higher average temperatures create a more favourable environment for mosquitos, and they are therefore able to re-establish themselves at our latitudes.

Jellyfish

The Balearic Islands, the Canary Islands, the Gulf of Mexico, the coasts of Japan and Australia are all popular holiday destinations, and the number of jellyfish has risen sharply around the world in recent years. Rising sea temperatures create favourable conditions for the reproduction and growth of jellyfish, for example in the Mediterranean. In Australia, populations of cnidarians are spreading further south, including species of box jellyfish. They are amongst the most poisonous animals in the world. The situation is similar in the Gulf of Mexico.

Jellyfish stings can cause a variety of symptoms, ranging from mild skin irritation to severe allergic reactions. For sensitive people, the poison of certain species can even be life-threatening and can lead to serious medical emergencies or even death without medical treatment. Immediate medical attention is therefore essential for survival in these situations.

Travel medicine centres

You can get medical advice on travel vaccinations, what to do and other measures to protect against illnesses at the following centres, among others: