Situation actuelle en France de l'encéphalite à tique

Tick-borne encephalitis in eastern France

Each y a few cases of TBE infection are described in Alsace, France which lies at the occidental limit of the endemic zone of tick-borne encephalitis (TBE). Hence we carried out a retrospective epidemiological and clinical study of TBE infection in Alsace. Data were collected from serological results sent to the Institut de Virologie (Université Louis Pasteur) in Strasbourg. All samples positive for specific IgM against TBE were retained. The physician in charge of each patient was asked to provide clinical, epidemiological and biological data and with his agreement the medical file was referred to us. Since 1968, 64 cases of TBE infection, occurring between April and November, had been described. In 56% of cases, flu-like symptoms preceded neurological symptoms. Most patients had meningitis (54%) or meningoencephalitis (34%). There was no death due to TBE. Two areas were more highly endemic for the disease: the Guebwiller valley in low mountain country and the Neuhof forest, near Strasbourg in the plain of Alsace. In the last 2 y of the study, a third zone seemed to emerge, in the Munster valley. This epidemiological survey revealed the existence in Alsace of 2 endemic zones of TBE with a third zone possibly emerging in the last few y. The survey must be continued to follow the evolution of the disease.

[Tick-born encephalitis]

INTRODUCTION

Tick-borne encephalitis (TBE), a disease contracted through tick bites, is caused by a Flavivirus. Its geographical distribution comes from the geographical distribution of the reservoir of infection--i.e., mainly the tiny mammals living in the forests and bushes. The endemic area spreads from the Rhine to the Urals, from Scandinavia to Italy and Greece.

CURRENT KNOWLEDGE AND KEY POINTS

Symptoms usually evolve in three phases: at first a nonspecific phase with fever and myalgia, then an afebrile phase, and finally a phase with neurological manifestations, such as meningitis, meningoencephalitis and/or myelitis, and fever. Motor neurological sequelae are possible. The cases occurring in the East are characterized by their greater severity compared to those occurring in the West. The diagnosis, easily established given a history of a tick bite in an endemic area, is confirmed by the presence of specific IgM in the blood and/or cerebral spinal fluid.

FUTURE PROSPECT AND PROJECTS

There is no specific treatment. Prevention consists of individual prophylactic measures (self-examination and systematic extraction of ticks after exposure, use of repellents), and in immunization. The vaccine, prepared from inactivated viruses, should be used for target populations, that is, for people exposed to tick bites during their professional or leisure outdoor activities.

[Infections associated with pets]

INTRODUCTION

Domestic pets can transmit numerous infections, including bacterial, parasitic, fungal, and viral diseases. This paper reports the epidemiologic, clinical, therapeutic and prophylactic data of these zoonoses.

CURRENT KNOWLEDGE AND KEY POINTS

The routes of transmission are various. Bites and scratches are the most common health hazards and result in localized infections. Pasteurellosis, various aerobic and anaerobic infections, and cat-scratch disease are predominant. Bites are treated by cleaning the wound, rabies and tetanus prophylaxis, and the appropriate use of antibiotics. Other infections are transmitted through cutaneous, mucous, digestive or respiratory routes, by direct contact with the pets, excreta, or by arthropods. The most common are gastrointestinal (campylobacter, salmonella, yersinia, parasites, etc), dermatologic (dermatophytoses, scabies, cutaneous larva migraines, etc.), respiratory (psittacosis, etc.), and multisystemic (toxoplasmosis, toxocariasis, leishmaniosis). Certain people are at high risk for diverse diseases: small children (toxocariasis, helminthiasis), pregnant women (toxoplasmosis), and immunodeficient patients (cryptosporidiosis, salmonellosis, systemic pasteurellosis). These infectious diseases can be partly prevented by avoiding contact with diseased animals, and by washing the hands following exposure to pets or pet-derived excreta. Specific vaccines for humans and pets, as well as worming pets regularly, form an important part of the prevention. Veterinarians must discourage the keeping of wild or exotic animals as pets.

FUTURE PROSPECTS AND PROJECTS

National health survey institutions and new communication systems can improve our knowledge about the real epidemiology of pet-transmitted zoonoses.