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There are several other diseases besides BSE which belong to the group of transmissible spongiform encephalopathies (TSE). Although most mammals can be experimentally infected with the agent of these diseases, generally only single representatives of the orders Artiodactyla (cloven-hoofed animals), Carnivora (carnivores) and Primates (humans and monkeys) are naturally infected in the field. An overview of the current state of knowledge on TSE in several species like exotic ruminants, deer, mink and cats is presented. Etiological, clinical, anatomic-pathological and epidemiological aspects are described.

Civil air traffic moves in an altitude that is dangerous for human beings without technical aids. Low temperature and humidity, reduced air pressure combined with oxygen pressure, seasonal depending high concentration of ozone and cosmic radiation may also be risk factors. Further risks on long haul flights may be jet lag, risk of economy class syndrome and contact with permethrin, because of disinsection before take-off out of tropical regions. The aim of an airline is to offer good cabin air quality, comfort and security for all passengers, may they be healthy, old, disabled or sick. Medical incidences on board arise and passengers expect modern equipment such as doctor's kit and defibrillators.

An estimated 20,000 to 30,000 cases of imported malaria are annually diagnosed in industrialised countries. Some 700 of them concern Swiss travellers and foreign guests. Exposure prophylaxis and chemoprophylaxis for high risk destinations lower the risk of malarial disease. The latter is defined as regular intake of antimalarial drugs in subtherapeutic dosage in order to suppress the development of clinical disease. Drugs are usually taken from one week before travel until four weeks after return from an endemic area. Mefloquine, doxycycline, chloroquine plus proguanil, and presumably soon also atovaquone plus proguanil are available in Switzerland for chemoprophylaxis.

Toxoplasma gondii and Neospora caninum are phenotypically and phylogenetically closely related cyst-forming coccidia, both of which may cause abortion in livestock animals. T. gondii exhibits also zoonotic potential by causing diaplacental infections in the human fetus and harmful infections in immunosuppressed individuals. Humans get infected either by consuming inappropriately prepared cyst-containing meat or by ingesting oocysts originating from cat feces. Therefore, in order to assess infection risk we need to have knowledge on the prevalence of the parasite in consumable meat and thus slaughtered animals. So far, no data indicate any zoonotic potential for N. caninum. Due to its high economic impact in the bovine production in Switzerland, we included this parasite in the present study as well. The prevalence of both parasite species were investigated by PCR in muscle and brain samples of slaughtered bovines, sheep, pigs and horses. Comparatively, a serum sample from each animal was simultaneously tested serologically by a Toxoplasma-P30-ELISA and a Neospora-SA-ELISA. The prevalences determined by the T. gondii-PCR were the followings: adult cows 3%, young bulls 2%, young cows prior to gravidity 6%, calves 1%, sheep 6%, horses and pigs each 0%. For N. caninum, the PCR-prevalence was 2% for adult cows and 0% for all other animal groups. Conversely, the seroprevalences were much higher for both parasite species and all animal groups, with the exception of the fattening pigs. However, as T. gondii was principally detectable in bovine (cows and calves) as well as in sheep meat, the consumption of this meat harbours a potential infection risk for humans. In contrast, the lack of any parasite detectability in fattening pig and horse meat allows to consider this infection source as neglectable when compared to bovine and ovine meat.

Cyst-forming coccidia may cause significant losses in livestock, primarily due to abortion, loss of young animals and neuromuscular diseases. Rather recently, Neospora caninum has been recognized as one of the major protozoal abortion-inducing parasites in cattle. The present study addressed the performance of different diagnostic tools (in vitro-cultivation; histology; immunohistochemistry; serology; PCR) suitable for the direct or indirect detection of N. caninum. By PCR, Neospora-DNA was detected in 24 brains (29%) from 83 bovine abortion, many of these brains were simultaneously characterized by histopathological findings typical for a protozoal, cerebral parasitosis. The diagnostic methods were furthermore assessed using samples of different tissues and body fluids from three experimentally Neospora-infected pregnant cows and their foetuses. The diaplacental passage of N. caninum to the foetus was successful in two of the three cases. In these two cases, PCR was positive for different foetal organs and, additionally, for the abomasal and amniotic fluid. The successfully infected cows developed anti-Neospora serum antibodies between 10 and 17 days post infection, foetuses remained serologically negative in all cases. The results obtained in the present study demonstrated the usefulness of PCR, complemented by serology, for the specific diagnosis of bovine neosporosis. Such tests may prove suitable to perform epidemiological investigations. Taken together, our data indicated that prenatal neosporosis may be an important cause of infectious bovine abortion in Switzerland.

The Swiss Working Group for Health Advice to Travellers regularly publishes its recommendations for malaria prophylaxis and vaccination as supplement to the 'Bulletin' of the Federal Office of Public Health. In this review the strategy with respect to information, to clever behavior abroad, to chemoprophylaxis and immunization prophylaxis is analyzed. A critical evaluation of emergency self-therapy describes remaining questions in particular.

Swissair's 3000-odd cockpit and cabin personnel spend an aggregate total of one year in the tropics for every ten years of flight service with the airline. Since 1975, company policy has been to issue all crews with a 'treatment dose' of anti-malaria medication to be taken if malaria contraction is suspected. Up until 1985, this treatment dose medication was recommended to crews for cases in which malaria was suspected even though chemoprophylactic medication had been taken. Since 1985, crews have been advised to rely solely on the treatment dose (i.e. not take any chemoprophylactic medication) if they are exposed to only low or moderate malaria risk. Experience so far has been encouraging: There has been no increase in incidences of malaria; the approach has been widely accepted among crews; the treatment dose (1%) has been judiciously used; the amount of chemoprophylactic tablets issued has declined; the number of repellents issued has increased; and the fear of side-effects from anti-malaria medication has decreased. The risk of contracting malaria-about one case per 200 to 300 years of service-is accepted. The question of whether and to what extent these experiences, which have been recorded among a small and selected group of the population, can be applied to other frequent flyers merits further investigation.

A modified intrauterine aspiration technic for detection of endometrial adenocarcinoma and its precursors has been described. This method which is simple, inexpensive and requires neither anaesthesia nor analgesia, allows cyto-histologic diagnoses of endometrial lesions. A correct cytologic or cyto-histologic diagnosis was made in 93.9% of the 277 cases examined. Of the premalignant and malignant endometrial lesions, the diagnostic accuracy was 100%.