The Mediterranean, its Sun, its Beaches, and... its Diseases!

Who doesn't dream of going on holiday to the sea with their dog? Travelling with your dog, showing them the sea, sand, and beaches, is a wonderful experience. Nevertheless, there are a few things to consider if you want to take your dog on a sunny holiday. There are entry regulations to observe and local diseases from which you must protect your four-legged friend. Here, we have compiled some precautions to take when travelling to the Mediterranean region with your dog.

Travel Preparations

Anyone who has ever had the opportunity to take their dog abroad knows that the dog's papers must be up to date so that they can leave the country and re-enter Switzerland. Therefore, we recommend that you contact your veterinarian to ensure that your dog is vaccinated against rabies and has a valid pet passport. Depending on the country you are travelling to, additional blood tests and examinations may be required. Therefore, especially if you are leaving the European Union, remember to inquire about entry requirements with the authorities of the destination country and your veterinarian well in advance.

For the journey itself, you should remember to bring sufficient fresh water (also factoring in any potential traffic jams), a travel water bowl, and a cooling mat so that your dog does not suffer from the heat. If you are flying, you should start accustoming your dog to their carrier or mobile kennel several weeks before departure so that they feel comfortable during the journey.

If your pet suffers from travel sickness, ask your veterinarian for anti-nausea tablets.

Finally, you must prepare your dog primarily for the stay at the destination.
For this, we recommend assembling a small first-aid kit containing liquid and cream disinfectants, compresses, bandages, an anti-diarrhoea preparation, a tick remover, a thermometer, nail clippers, latex gloves, socks (to protect a paw bandage), a clean towel, and scissors or a small clipper.

Last but not least, you should protect your dog from local diseases! This is because the Mediterranean region has disease vectors that do not occur here in Switzerland. It is an endemic area for dirofilariasis, better known as "heartworm disease," and leishmaniasis.

Heartworms, Causes of Dirofilariasis

Heartworms (Dirofilaria immitis) are transmitted by mosquitoes (Culex pipiens). When bitten by an infected mosquito, larvae are injected into the dog. These travel through the bloodstream and develop into adult worms, which primarily settle in the pulmonary arteries and the right side of the heart. These adult stages begin to produce larvae, known as microfilariae, after approx. 6 months, which migrate to the capillaries of the subcutaneous tissue. If the infected dog is then bitten by a mosquito, it ingests these microfilariae with its blood meal. In the mosquito, the microfilariae develop into larvae that can be transmitted to another dog during a subsequent blood meal.

The spread of the parasite depends on many environmental factors, including, of course, the presence of numerous mosquitoes. The regions with the highest risk are Southern Europe (Portugal, Spain including the Canary Islands, Southern France, Italy, the Balkan countries, Greece), the Czech Republic, Bulgaria, and Romania, as well as North Africa. Because global warming favourably affects mosquito reproduction, the risk areas are expanding.
The risk period for infection varies by region but normally extends from April to October.

Heartworms are the cause of what is known as "canine cardiovascular dirofilariasis". The disease also occurs very rarely in cats. The clinical course of dirofilariasis is usually chronic. Most affected dogs initially show no clinical signs of infection for years. Only gradually do symptoms such as chronic cough, respiratory distress, pulmonary haemorrhages, followed by weakness and sudden collapse, appear. If heart failure develops, the animal also shows loss of appetite, dehydration, oedema, and weight loss in addition to the chronic cough. Blood clots can form, which can block vital vessels and thus lead to the sudden death of the dog.

Diagnosis is made by detecting microfilariae in a blood smear. Various treatment protocols are available depending on the severity of the infestation.

For dogs taken on trips, prevention is therefore crucial. It is also effective and easy to implement. It is based on the oral administration of a deworming agent. This kills the larvae of D. immitis that have developed in the preceding 30 days, thus preventing the onset of the disease. For animals that have stayed in a risk area for less than a month, a single treatment immediately after returning to Switzerland is sufficient. For dogs staying in a risk area for several months, the deworming agent must be administered once a month and then again after returning to Switzerland. It is also advisable to test your four-legged friend after a certain period to ensure they have not been infected.

It is also advisable to combine this oral prophylaxis with externally applied prophylaxis.  This means that dogs should be protected from mosquito bites with an insecticidal Collar or spot-on preparation.

Leishmaniasis, a Widespread Disease

In Europe, leishmaniasis is caused by the single-celled parasite Leishmania infantum. In fact, there are many different pathogen variants worldwide responsible for leishmaniasis. The vectors of this parasite are sandflies (Phlebotoma), which are found throughout the Mediterranean region, as well as in Africa and the Middle East, wherever canine leishmaniasis is endemic. They can sometimes also be found in Northern France and, more rarely, in Southern Germany or Southern Switzerland. Today, two factors increase the risk of contracting leishmaniasis outside endemic areas: global warming and the (involuntary) long-distance transport of sandflies by planes, trains, and cars.

The risk season varies from year to year and from region to region. It normally begins in April and ends at the end of November.

The dog is the main host of L. infantum, but the microscopic parasite can also be transmitted to other mammals, occasionally even to humans.

Infection usually occurs through the bite of a sandfly carrying leishmania. Very rarely, puppies of an infected mother dog can become infected before birth via the uterus. The leishmania develop in the white blood cells, multiply, and spread throughout all organs of the affected dog. The time from infection until the first symptoms of the disease appear is usually several months or even years. However, many dogs remain asymptomatic carriers, meaning they show no signs of the disease despite being infected.  Some dogs can even naturally eliminate the pathogens themselves. There are also dog breeds (often local "breeds," also called "village dogs") that have developed resistance to the disease.

The clinical manifestation of the disease is therefore very individual. Not all factors leading to the disease are known. However, we do know that it is influenced by the dog's immune response and the presence of other co-morbidities.

Leishmaniasis is a disease with a wide spectrum of more or less specific symptoms. More specific signs of the disease include more or less severe skin changes and organ damage, leading to lethargy, loss of appetite, emaciation, anaemia, eye problems, and kidney failure.

Other symptoms are less common and rather atypical, making diagnosis difficult, such as nosebleeds, eye and joint damage, or epilepsy.

Diagnosis is made through blood tests. The extent of the disease is assessed based on further examinations. Various treatments and therapy protocols are available depending on the severity of the infection and symptoms. However, it is often a severe, lengthy, and expensive treatment. Furthermore, relapses are common.

A common active ingredient used to treat leishmaniasis, allopurinol, has the side effect of forming urinary stones. Dogs receiving this treatment must therefore be given a special low-purine food to reduce the risk of xanthine stone formation.

As this is a complicated disease, an effective prevention strategy is particularly important. Prophylaxis for travelling dogs is primarily achieved by applying insect repellents or insecticides to the dogs. These active ingredients are available in the form of Collars, sprays, and spot-ons. They have an excellent repellent and/or insecticidal effect. The aim is to avoid sandfly bites or interrupt the transmission of leishmania to prevent infection in dogs.  To date, no resistance to insecticidal active ingredients has been observed, so these prevention methods are very effective in reducing disease transmission.

In addition to these topical treatments, you should also take the following measures for optimal protection:

• Keep your dog indoors at night, especially at dawn and dusk when sandflies are particularly active
• Use insecticidal sprays or vaporisers indoors
• Install mosquito nets on doors and windows
• Use insecticide-impregnated mosquito nets in sleeping areas

All these measures will enable you to significantly reduce the risk of bites from sandflies and mosquitoes. This way, you can enjoy a wonderful holiday with your four-legged friend and savour the sea and sun without worries!