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Francisella tularensis is a facultative intracellular pathogenic bacterium, which causes disease named tularemia. For the entrance to the host cells Francisella uses host's cell mechanisms by which it is incorporated into cell phagosome. Subsequently, it escapes from phagosome to cytosole where bacterial growth takes place. Some of bacteria are cleared from cytosol by autophagy, from another ones dsDNA is released. This DNA is recognized by cytosolic receptors, which form inflammasome complex. Inflammasome sets off pathway leading to the death of infected cell. Since the penetration to the cell Francisella modulates cell signallization in its own benefit to ensure enough time and nutrients for its growth. Francisella do not act only in the infected cells, where it reduces recognition of itself and clearance from cytosol, but it also induces secretion of factors, which moderate activation of adaptive immunity of the host. Key words: Francisella, tularemia, fagosome, inflammasome, autophagy, adaptive immunity

Tick-borne diseases are caused by a group of pathogenic microorganisms which are transmitted between animal and human population by vector which is most frequently tick. Evaluation of danger and perils of these diseases is important due to prevention and monitoring of current situation development. The most common tick-borne diseases in the Czech Republic are borreliosis, tick-borne encephalitis and ehrlichiosis. Rarely can we encounter bartonellosis, babesiosis, rickettsiosis and tularemia. All these diseases can have serious consequences and in critical cases they can result in death of the infected person. One of the basic and the most important of preventive measures which lower the risk of the infection by any tick-borne disease is prevention of tick encounter and eventually vaccination. Due to continual global warming we can expect that in near future ticks will spread even to locations which have been so far not suitable for their development. We can expect that we will even more frequently encounter tick-borne diseases - including diseases which were formerly not found in our territory or were very rare. As a part of health education it will be needed more to get known basic information of tick-borne diseases and their prevention. Different educational centres are an ideal place for...

Francisella tularensis belongs to the most important biological agents potentially applicable in biological warfare and bioterrorism. High virulence, easy and rapid spread among individual vectors, stability of the cells in aerosol and good penetration into the lungs make F. tularensis one of the most important biological warfare agents in both human and veterinary medicine. The text provides comprehensive data about tularaemia and outlines the fate of the pathogen in the host. Special attention is paid to immunological aspects of the disease, therapy, and diagnostic methods.

In the recent years, floods have been an increasingly common natural phenomenon in the territory of the Czech Republic. I have chosen the bachelor thesis about the topic ?Infection diseases in connection with floods, protection of inhabitants and IRS forces when realizing clean-up operations in disaster areas? because I have been employed with the village of Loučovice in the position of the secretary. Due to its position on the flow of the Vltava River and below the water dam LIPNO 1, the village of Loučovice is threatened with both natural and special floods; therefore, timely awareness of citizens in case of possible threat is a basic prerequisite for the realization of effective measures for the protection of lives, health and property but also for possible elimination of effects of the flood. The paper summarizes possible causes of natural and special floods, which, in addition to considerable property damages, bring health risks too. As for the findings from the areas damaged by floods, I have identified the mostly occurring infection diseases after the flood goes off. In addition to the affected inhabitants, members of the intervention forces of the Integrated Rescue System and volunteers, who participate in rescue and clean-up operations, are also exposed to the infection diseases. Furthermore, I specify the evaluation of the statistical data identified in the system EPIDAT, which is used for monitoring of the epidemiological situation in the Czech Republic. The purpose of my paper is to gather collective information for the Flood Commission at the village of Loučovice. It concerns an overview of IRS forces and roles of the territorial self-governing units and their activity at the time of an extraordinary event. The result is an up-dated list of telephone contacts, so-called crisis card, recommendations for protection of property against the impact of the flood wave, possibilities of protection of water sources and the way of emergency supplies of drinking water, which are related to the threat of contagion with infection disease.

Francisella tularensis, from the family Francisellaceae, is the aetiological agent of a zoonosis called tularaemia, spread throughout the northern hemisphere. The infectious dose is extremely low (10 CFU/ml) and the infection causes severe diseases or even death if untreated. The transmission to humans is always related to animals, either by a direct contact or by a contact with the environment contaminated by them. Clinical symptoms of the disease can vary depending on the point of entry of the infection. Tularaemia may also occur without any local symptoms or can be manifested by a combination of the symptoms of various typical clinical forms. F. tularensis is a fastidious bacterium and it is rarely diagnosed by blood culture.

Francisella tularensis belongs to the family Francisellaceae. It is the aetiological agent of a zoonosis called tularaemia, spread throughout the northern hemisphere. Currently, several subspecies of F. tularensis may be distinguished with various pathogenicity and geographical distribution. In human medicine, only sporadic infections or local epidemics are reported. Given the fact that F. tularensis is highly pathogenic for humans and is easily spread by aerosol, water or food, it may be exploited as a biological weapon. It belongs to fastidious strains requiring specially prepared culture media.

The topic of my thesis called "Health risks to the area affected by flooding and measures to overcome them in the territory of the Czech Republic" I have been engaged in over the recent years affected and still affects all of us. I think this topic is actual as the Czech Republic was hit by floods several times in the past. It is still necessary to develop new measures to minimize the consequences on the lives and health of the population after the flood. In the theoretical part of my thesis, I described the most common infectious diseases associated with the consequences of floods and I was trying to point out the measures which are needed for the rescue and liquidation activities in this natural disaster. The described measures are important to minimize the infectious diseases which threaten the population. To find the practical results, I prepared the questionnaire that I gave to the random people who were involved in the floods in 2002, 2006 and 2009 in the South Bohemia and Pilsen regions. Then, I compared the results of the infectious diseases with the statistical data of the reported infectious diseases in the Czech Republic. The study tested the hypothesis whether the population at the time of the floods was duly and properly protected and informed about the health risks immediately after the flood. This hypothesis can be closed as confirmed as I was convinced that the measures were sufficient to protect the population against the health risks. I dare to say that there are no health risks during the floods, because the only one practical and theoretical knowledge talk about preparing for the evacuation due to a possible flooding.

Francisella tularensis is an intracellular bacterial pathogen and is the causative agent of tularemia. Human become infected when manipulating with infected animals (usually rodents) or via arthropod vectors. In spite of the high virulence of the microbe still very little is known about its overall interaction with host cells and virulence factors identified to date show properties different from other bacterial species.

Tularemia was first described 90 years ago by McCoy as a disease of animals. At the beginning of twenties it was recognised by E. Francis as a disease transmittable from animals to man. Tularemia is caused by a gram-negative microbe Francisella tularensis. Epidemiological and clinical manifestations of the disease are highly diverse. The characteristic sign is the primary complex consisting from an initial ulceration and a regional lymphadenitis. In the Czech republic tularemia was first identified in 1936 in the south of Moravia and for the next years it occurred sporadically or in epidemic form also in the western Moravia, in north-west and east of Bohemia. It affected persons manipulating with the diseased animals, namely with hares, workers in animal farms and those working in cold sections of sugar mills. After a longer pause, during the last six years, the incidence of tularemia has increased again. That is why we decided to renew the understanding of the disease.

Southern Moravia is one of the areas where there are long-term natural foci of tularaemia. In 1994 in the Breclav district an exacerbation of the disease was recorded in hares. During autumn hunts a positive reaction was recorded in 5.75% of examined hares. An elevated seropositivity persisted also in subsequent years and at the same time a higher human morbidity in the mentioned region. The objective of the investigation was to assess the causes and circumstances which led to the exacerbation of old known but in recent years quiescent foci in the mentioned region. To this end 350 small terrestrial mammals were examined. In one case it proved possible to detect the causal agent in Microtus arvalis. By examination of arthropods it proved possible to isolate 33 strains, i.e. 32 strains from ticks Dermacentor reticulatus and one strain from Ixodes ricinus. The results of the examination revealed that tularaemia as a classical infection with a natural focus may persist in areas where there are prerequisites for survival of the causal agent in the environment. One of the important factors of the environment are susceptible individuals (hares, small terrestrial mammals) as well as blood sucking arthropods as vectors of the disease.

The first epidemic of ulceroglandular forms of tularemia acquired in coincidence with the manipulation with tularaemic hares took place in 1936 in the surroundings of Breclav and Valtice. The largest epidemic took place in the 1960's when hundreds of agricultural workers in the initial phases of the production of sugar within sugar refineries were afflicted by pulmonary forms of this disease. In the subsequent period which was interrupted only by smaller local epidemics, the number of new cases were gradually decreasing to the minimum at the beginning of 1990's. However, since 1994, the number of cases has began to increase again, namely those afflicted by ulceroglandular and oroglandular forms. OBJECTIVES [corrected]: In consequence of the long absence of this disease in clinical practice, the diagnostic awareness has decreased, and therefore the author has decided to indicate and review the current basic data on epidemiology and clinical manifestations of tularaemia.The author has analysed the documentation of 577 of adults afflicted by tularemia and medically treated at the clinic of the Faculty Hospital in Brno in the period form 1959 to 1999. The study reviews the onset of the disease and the pathway of transmission of infection and its clinical manifestation.Following the long-termed sporadic occurrence of tularaemia after major epidemics of pulmonary forms of this disease in 1960's, interrupted only by smaller local epidemics, the incidence has began to increase again in 1994. The number of pulmonary forms has decreased whereas the occurrence of ulcerulceroglandular and oroglandular forms has increased. Hares have become the source of infection again.The fact that tularemia has repeatedly become a threat in Southern Moravia should be taken into account in the assessment of diagnosis in cases with unclear lymphadenitis and febrile states which defy the penicillin treatment especially in winter. (Tab. 3, Fig. 3, Ref. 23.)

As a continuation of Libich's monograph (Tularemie. Prague, Avicenum 1981) the author presents findings assembled in experiments pertaining to postinfectious immunity on a model of intracellular infection with the microorganism Francisella tularensis.

The authors described two cases of the ulceroglandular form of tularaemia where the infection was transmitted to man after a sting by a tick in the Brno area. The incubation period was two weeks and 11 days resp., the course of the disease, in particular in the female patient was relatively severe and complicated, obviously due to the late establishment of the diagnosis and thus delayed aetiological treatment. The authors recommend to consider a tularaemic aetiology in case of a febrile disease which develops within two weeks after a tick sting, in particular if the site of the prick becomes inflamed and regional lymphadenitis develops.

The authors examined, using the tularin test of Soviet make a total of 1380 employees of 14 work places of the national enterprise Zelenina in Brno. These work places are concerned with the purchasing, storage, distribution and sale of fruit and vegetables, grown among others also in South Moravian areas contaminated with tularaemia. They detected a total of 71 positive reactions concentrated mainly among long-term workers of the main storage places and transport departments of eight plants, i.e. Boskovice, Prostĕjov, Brno-town, Breclav, Trebíc, Brno-rural area, Slavkov and Znojmo, where the total tularaemia immunity rate varied between 4.88 and 12.30%. The distribution of positive cases signalizes with a high probability the occupational character of thus retrospectively detected cases, similarly as in the sugar plants and in the enterprise Fruta where products from the above area are processed. The source of infection are most probably rodents and the medium of transmission is probably fruit and in particular vegetables from the South Moravian area with tularaemia. The author recommends to introduce provisions to protect workers with risk occupations and possibly also consumers buying these products in retail shops.

Three cases of granulomatous purulent colliquative lymphadenitis showed histologioal similarity with caseous tuberculous lymphadenitis as well as with some other granulomatous lymphadenites. It was only a positive serological test that suggested the diagnosis of tularemia.

The examination comprised 656 cases of brucellosis, 208 cases of pseudotuberculosis, 31 cases of yersiniosis, 13 cases of tularemia and 120 cases of pasteurellosis. In brucellosis, changes in liver, spleen and sexual organs prevailed. The macroscopy of the changes was typical. A histiocytic granuloma of tuberculoid type was found by histological examination. Owing to caryolysis, the central necrosis of granulomata contained a conspicuously small amount of nuclear detritus, and big cells of Langhans type were found in the histiocytic layer. A layer of round-cell elements constantly occurred on the periphery of the necrosis and peripheral fibrotization was observed in older granulomata. Pyogenic component was almost absent. Pseudotuberculosis and yersiniosis were characterized by septic tumour of the spleen and alterations in liver, lungs, kidneys, and the terminal section of ileum. In pseudotuberculosis necrotic changes occurred in bone marrow and in processus vermiformis. The changes were histologically limited by the formation of granulomata and necrosis with characteristic karyorrhexis and with tht occurrence of masses of bacteria in the necroses. Neutrophiles were constantly found to be present in the changes, whereas peripheral fibrotization was not typical. In tularemia, besides spleen tumour, alterations in lungs prevailed, having a vitreously smoky appearance, bacon-like on cross section. From the histological point of view, a histiocytic granuloma of tuberculoid type was involved. Its only differences from brucellosis were the larger content of nuclear detritus owing to karyorrhexis and the occurrence of erythrocytes in the lung alterations where marked peribronchial and perivascular infiltrates were present. The typical location of spleen alterations was the periphery of Malpighian corpuscles. Staphylococcosis was differentiated by a purulent nature of the changes and pasteurellosis by a constant finding of pneumonias and tracheitis.