Leishmaniasis is caused by a protozoan (Leishmania sp.), which is spread between animals by sandflies.  Dogs can be bitten up to 100 times an hour during the sand fly season, which begins in May and ends in September.   The disease is present in Europe, the Middle East and many tropical countries.  Several cases are diagnosed in dogs each year in the UK where infection has been picked up abroad and the organism can cause disease in people.

Affected animals may lose weight, develop skin lesions and swollen lymph nodes, become lame and have recurring fever.

Babesisis (or Redwater) is a disease of cattle and other mammals, caused by the protozan parasites Babesia bovis, B. bigemina, B.divergens and others.  The organism develops into the red blood cells of affected animals.  Different species of the organism affect different animals.  The organism is tranmitted between animals by ticks but can also be spread by contaminated instruments or needles.

Babesiosis occurs worldwide and bovine redwater is constantly present in some areas of the UK.  In Europe, particularly in southern France, dogs are at risk of infection and there is a possibility that dogs  from the UK, on holiday with their owners in Europe, may return home with the infection.  Signs of disease may include a fever, loss of appetite, the passage of red / brown urine, anaemia and weakness.

Infection by a parasitic worm called Dirofilaria immitis may result in heartworm disease.  The adult worms live in the heart and blood vessels.  Dogs are most commonly affected, but the worms  can also infect cats and ferrets.  The intermediate stage of the worm, called the larva, is transmitted between animals by mosquitoes in hot countries including Spain and France.  Clinical signs vary but may include coughing, breathlessness and intolerance to exercise and can lead to death.

Ehrlichiosis is caused by a rickettsial parasite that can infect the blood cells of several species including dogs, horses and people.  It is transmitted by ticks.  The disease occurs in North Afica and in several European countries.  Clinical signs vary but include fever, loss of appetite, anaemia, stiffness and reluctance to move.  Prolonged bleeding may also be seen.