Proceedings of the WSEAS International Conference on ENVIRONMENT, MEDICINE and HEALTH SCIENCES
Risk Analysis of Infections Caused by Zoonoses of Alimentary Origin in the Selected Region of the Czech Republic
PAVLA KREJCOVA, JIRI DVORAK, FRANTISEK BOZEK Civil Protection Department University of Defence 65 Kounicova, 662 10 Brno CZECH REPUBLIC [email protected] http://www.vojenskaskola.cz
Abstract: - The paper is aimed at risk analysis of infections caused by zoonoses of alimentary origin. The bacterial, viral, and parasitic agents were investigated. Individual risks of particular zoonoses in the Czech Republic were compared with the same indicators in the South Moravian region. The implementations of effective countermeasures were designed for unacceptable risks to mitigate them.
Key-Words: - Alimentary disease, bacterial agents, individual risk, measure, parasitic agents, risk analysis, viral agents, zoonoses.
1 Introduction with their endemic occurrence, mainly due to tourism Zoonoses of alimentary origin represent a significant and jobs abroad. group of diseases. The casual agents may be bacteria, The group of alimentary toxoinfections represents moulds and their toxins, viruses, parasites and prions. a problem, which is difficult to solve. Anti-epidemic The diseases may develop through consuming measures taken by doctors, vets and food producers only contaminated food and water as well as through partially influence the tendency of their occurrence. insufficient hygiene during food processing. Food Salmonellosis has been a problematic zoonosis for many security is currently a much debated topic covering years and recently campylobacteriosis has been the phases of production, processing, storage, occurring more and more often. distribution and consumption. The aim of risk analysis is The group of alimentary poisoning from food occurs to determine the critical types of zoonoses, minimize the only occasionally with epidemics only in case of risk of contagion with the indicated critical alimentary collective catering. Botulism is the most significant diseases and increase the level of population health disease and its occurrence is often caused by consuming protection. The implementation of measures is carried home-made vegetable and meat tins. out in close co-operation with state administration bodies Salmonellosis is a frequent alimentary intoxication and requires public awareness. caused by the bacterium of Salmonella. These bacteria primarily occur in the alimentary tract of animals and people and through excrements contaminate environment and food. Poultry is a significant reservoir 2 Current State Analysis of etiologic agents. Risk lies in the consumption of Alimentary diseases are divided into food infections and insufficiently cooked meat and eggs [1, 3]. Rodents, wild poisonings depending on the character of birds and insects may also spread the disease. microorganisms causing disease and the mechanisms of Interhuman transfer is extremely rare. The infectious their effects. Alimentary intoxications are caused by 4 dose is 10 of bacteria. Epidemics outbreak less often in microorganisms, which are transported by food or water the catering facilities of closed type (school dining halls, into human alimentary tract where they reproduce and nursery schools dining halls) than in the catering cause a disease. Toxoinfections are diseases caused by facilities of open type (street stalls, confectioneries). endotoxins of bacteria, which affect intestinal mucous Infections spread mainly by sweets and finished food membrane [1, 2]. into which eggs are added at the end of heat treatment The group of alimentary infections with and not by meat products as it used to be [2]. predominantly faecal-oral way of transport is Bacterium from the Campylobacteriaceae family significantly affected by a “human factor“ during the causes campylobacteriosis. The risk of infection lies whole food chain. Acute diarrhoeic diseases of both mainly in low hygiene during handling poultry in bacterial and viral origins are epidemiologically households and public catering facilities. Infection is significant, because they are imported from the countries transferred alimentary or directly by contact with an
ISSN: 1790-5125 23 ISBN: 978-960-474-170-0 Proceedings of the WSEAS International Conference on ENVIRONMENT, MEDICINE and HEALTH SCIENCES
infected animal. Interhuman transfer as well as congenital transport from mother with an acute form epidemics’ of campylobacter are rare. The infectious of disease [1, 2, 4]. dose is about 103 of bacteria. Epidemiological Teniases are parasitic diseases caused by Taenia significance increases together with the annual increase solium a Taenia saginata. Adult specimen live as in the number of affected people [1]. parasites mainly on a small intestine and can cause Listeria monocytogenes is also a monitored bacteria serious diseases of people and animals. People are causing alimentary disease. This microbe causes sources of infection and animals are carriers that, after infections among people and animals. Rodents help eating eggs of Taenia, let them grow in their muscles. these bacteria to sustain. They spread alimentary the The risk of infection arises from consuming raw or most often. The occurrence of listerioses is not high, but undercooked meat containing cysticerci. Faecal-oral the risk lies in high mortality, which can be up to 60% transport is also possible in case of low level of personal among sensitive individuals. Erysipeloid, brucellosis and hygiene [1, 2, 4]. tularemy belong to this group of diseases as well. Tularemy has a potential to be used as biological warfare agent [2, 3] due to its high level of dangerousness and 3 Used Methods extremely low infectious dose. The outcomes of analyses carried out by accredited Escherichia coli or yersiniosis caused by Yersinia microbiological laboratories at regional hygienic centres enterocolitica are the most significant intestinal and the State Medical Institute have been used in the infections caused by microorganisms triggering acute paper. Causal agents have been identified through direct diarrhoeic diseases. The infections are mostly methods including cultivation, microscopic detection, transported by faecal-oral way, dirty hands and direct imunofluorescence, Enzyme Linked contaminated food. The risk again lies in insufficiently ImmunoSorbent Assay (ELISA), and Polymerase Chain cooked food, unwashed vegetables and contaminated Reaction (PCR). Indirect methods have been used for water. The infectious doses are rather high, it is 9 detecting formed antibodies. The ELISA method and 10 bacteria in case of Yersinia enterocolitica [2]. indirect imunofluorescence have been used for Hepatitis A from Picornaviridae family represents diseases of viral origin. Viral diseases transported by the detection of antibodies. Microscopic detection, food show several differences when compared with imunofluorescence, ELISA and PC have been used for bacterial alimentary diseases. The infection does not rapid diagnostics. affect alimentary tract, but it gets directly to liver where The occurrence of selected zoonoses in a region and it attacks parenchymatic cells and reproduces there. The in the Czech Republic has been found out through the virus neither reproduces in food nor changes food EPIDAT programme. The EPIDAT programme is used sensorial properties, which makes its identification more by a hygienic service for obligatory reporting, evidence difficult. The zoonotic transport is unlikely due to and analysing the occurrence of infectious diseases in specific properties of viruses. The risk lies in faecal-oral compliance with corresponding legal amendment [6, 7] transport. Transport is possible through the vectors such and international regulations binding for the WHO as insects and water. The resistance of virus is rather member countries. high as it is not destroyed by common pasteurizing Brainstorming has been used for determining the temperatures and it maintains its virulence in frozen food levels of impact of individual infections [8]. for at least 1,5 year. The alimentary risk assessment is more complicated when compared with bacteria due to long incubation time (30 days in average) as well as long 4 Outcomes and Discussion and difficult proof of causal agent [1, 2]. The individual risks of diseases caused by selected The frequency of diseases caused by parasites is not zoonoses of alimentary origin have been calculated on high, but the effects on human organism are serious. the basis of data acquired from the EPIDAT programme Toxoplasma gondii is a causal agent of toxoplasmosis [5] and the Czech Statistical Office [9]. The values of and the disease outbreaks mainly among people with individual risks for the assessed zoonoses from 2003 to decreased immunity. The causal agent belongs to 2008 are shown in Table 1. coccidia, the life cycle of which requires several hosts. The individual risks of infections caused by diseases Felines are the final hosts and infectious oocysts grow in of bacterial, parasitic and viral origins have been studied. their intestines and are excreted into environment. The infections of bacterial origin have been chosen for People and other warm-blooded animals may become their pathogenity, speed of spreading and high frequency carriers. The risk of infection arises from consuming of occurrence. The parasitic infections have been chosen raw or undercooked meat containing tissue cysts, because of their difficult life cycle and unclear detection. rarely also from contact with an infected animal or
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Table 1 Individual risk of taking a disease caused by selected zoonoses of alimentary origin in the Czech Republic
-1 -1 Individual risk RI [person .year ] Type of disease 2003 2004 2005 2006 2007 2008 campylobacteriosis 1.96x10-3 2.50x10-3 2.96x10-3 2.21x10-3 2.35x10-3 1.93x10-3 salmonellosis 2.64x10-3 3.01x10-3 3.22x10-3 2.45x10-3 1.76x10-3 1.05x10-3 listeriosis 1.18x10-6 1.57x10-6 1.47x10-6 7.60x10-6 4.94x10-6 3.54x10-6 erysipeloid 8.82x10-7 9.80x10-7 7.82x10-7 7.80x10-7 4.84x10-7 3.83x10-7 tularemia 5.88x10-6 5.00x10-6 8.11x10-6 8.47x10-6 5.23x10-6 1.08x10-5 brucellosis 0.00 0.00 0.00 0.00 0.00 9.57x10-8 other intestinal infections 2.31x10-4 2.77x10-4 2.64x10-4 2.41x10-4 2.74x10-4 3.16x10-4 hepatitis A 1.12x10-5 6.86x10-6 3.15x10-5 1.29x10-5 1.24x10-5 1.58x10-4 toxoplasmosis 4.46x10-5 3.12x10-5 3.39x10-5 3.19x10-5 2.24x10-5 2.37x10-5 teniasis 9.80x10-7 8.82x10-7 2.93x10-7 6.82x10-7 9.69x10-7 1.91x10-7
Hepatitis A has been monitored due to its epidemic It results from the comparison of data in Table 1 and occurrence and dangerousness. The monitored bacterial Table 2 that the current individual risk of infections diseases include campylobacteriosis, salmonellosis, caused by zoonoses in the South Moravia region is listeriosis, erysipeloid, tularemia, brucellosis, and other comparable with the risk situation on the territory of all bacterial intestinal infections including yersiniosis and country. The situation in the region is more favourable in infections caused by Escherichia coli. The parasitic most cases (listeriosis, erysipeloid, tularemia, other diseases include toxoplasmosis and teniasis, viral bacterial intestinal infections, hepatitis A, toxoplasmosis diseases include hepatitis A. and teniasis), however it is exceptionally rather worse in Similar risk analysis resulting from the zoonoses of case of salmonellosis and campylobacteriosis). alimentary origin has been carried out for the inhabitants The highest levels of individual risks have been of South Moravia region. Tha data from the regional recorded for salmonelloses, campylobacterioses and hygienic centre and the Czech Statistical Office [9] have other bacterial intestinal infections. Yersinia been used for the analysis. The values of individual enterocolitica and Escherichia coli have been separately risks for the assessed diseases are shown in Table 2.
Table 2 Individual risk of taking a disease caused by selected zoonoses of alimentary origin in the South Moravia region -1 -1 Individual risk RI [person .year ] Type of disease 2003 2004 2005 2006 2007 2008 campylobacteriosis 3.06x10-3 3.66x10-3 4.52x10-3 3.08x10-3 3.03x10-3 2.52x10-3 salmonellosis 3.32x10-3 3.69x10-3 3.88x10-3 3.19x10-3 1.95x10-3 1.11x10-3 listeriosis 0.00 0.00 0.00 5.31x10-6 3.52x10-6 1.74x10-6 erysipeloid 0.00 0.00 0.00 0.00 0.00 0.00 tularemia 7.09x10-6 6.20x10-6 1.59x10-5 1.06x10-5 6.17x10-6 8.70x10-6 botulism 0.00 0.00 3.54x10-6 0.00 0.00 0.00 brucellosis 0.00 0.00 0.00 0.00 0.00 8.70x10-7 other intestinal infections 1.86x10-4 3.03x10-4 3.13x10-4 2.23x10-4 2.83x10-4 2.71x10-4 yersiniosis 5.49x10-5 4.78x10-5 6.19x10-5 4.16x10-5 4.58x10-5 4.00x10-5 Escherichia coli 1.20x10-4 2.05x10-4 1.88x10-4 1.26x10-4 1.66x10-4 1.44x10-4 hepatitis A 1.06x10-5 8.85x10-6 3.54x10-6 7.96x10-6 8.81x10-6 4.70x10-5 toxoplasmosis 2.57x10-5 1.68x10-5 2.39x10-5 3.01x10-5 1.94x10-5 1.91x10-5 teniasis 0.00 0.00 0.00 0.00 0.00 0.00
ISSN: 1790-5125 25 ISBN: 978-960-474-170-0 Proceedings of the WSEAS International Conference on ENVIRONMENT, MEDICINE and HEALTH SCIENCES
monitored in the South Moravia region. The levels salmonelloses and other intestinal infections is often of their risks exceed the referential level different by more than one level when compared with -4 -1 -1 RI = 10 [person .year ] published in the U.S. EPA other diseases and that there is approximately the same database [11] both in the region and the whole country impact of the above mentioned critical infections. and are therefore unacceptable. However, it is necessary As far as the risk development of diseases caused by to realize that in relation to other intestinal infections the the assessed alimentary diseases is concerned it may be sum of risks does not significantly exceed the referential stated that during the monitoring period it either value. As it seems from the regional monitoring the fluctuates in a relatively narrow interval (listeriosis, highest number of infections is caused by Yersinias. It is tularemia, other intestinal infections, toxoplasmosis, clear that a maximum attention has to be paid to the teniasis) or after an initial increase it decreases to the prevention of transfer of salmonella and values analogical or lower than at the beginning of campylobacteria, similarly as in the armed forces [12]. monitoring (salmonellosis, campylobacteriosis), as it is Mortality has been monitored and possible impacts of shown in Figures 1 to 3. diseases assessed in order to increase the informative An exception is the increased incidence of hepatitis A value of individual risks. It has been found out that most in case of which the risk of infection in 2008 increased deaths have been recorded among the citizens over more than 5 times in the region and by even more than 70 years old and rarely among children up to three years one level in the Czech Republic. We assume that reason and citizens from 50 to 70 years old. Deaths have not is the reduced immunity of population due to a long term been recorded in other age categories during the minimal incidence of the disease resulting in the monitoring period. The impacts of disease C have been increased sensitivity of the generation, which has not determined with the use of brainstorming and assessed in been affected by the disease so far. At the same time the interval C 1; 10 C N, where N is a symbol tourism was on the increase, especially in Prague, where for the set of all natural numbers. The final individual the situation was the most critical. -1 -1 risk RIC [person .year ] has been calculated according to The implementation of the following the equation (1): counterepidemic measures may be recommended in RIC = RI . C (1) relation to the unacceptable individual risk of infections The corresponding data with the final risk RIC for caused by campylobacteriosis and salmonellosis: 2007 (data on mortality in 2008 were not known at the a) sensorial check upon the purchase of food; time of data processing) are shown in Table 3. It is clear b) adequate heat treatment of food (minimum of from the table that the conclusions derived from 10 minutes at 72 C); the individual risk RI of individual diseases are c) to consume food immediately after preparation; analogical even after including the weight of impact and d) to store food in temperatures over 60C, or below thus derived from the final risk RIC. The reason is that 10 C; the probability of occurrence of campylobacterioses,
Table 3 Individual risks of diseases caused by selected zoonoses of alimentary origin in the Czech Republic (CZ) and the South Moravia (SM) Region in 2007 while considering the impact of diseases
-1 -1 -1 -1 Level of Mortality [person] RI [person .year ] RIC [person .year ] Type of disease impact CZ SM Region CZ SM Region CZ SM Region campylobacterioses 4 X X 2.35x10-3 3.03x10-3 9.40x10-3 1.21x10-2 salmonellosis 4 1 10 1.76x10-3 1.95x10-3 7.04x10-3 7.80x10-3 listeriosis 8 0 3 4.94x10-6 3.52x10-6 3.95x10-5 2.82x10-5 erysipeloid 4 0 2 4.84x10-7 0.00 1.94x10-6 0.00 tularemia 7 0 1 5.23x10-6 6.17x10-6 3.66x10-5 4.32x10-5 brucellosis 8 0 0 0.00 0.00 0.00 0.00 other intestinal infections 5 3 16 2.74x10-4 2.83x10-4 1.37x10-3 1.42x10-3 hepatitis A 6 1 1 1.24x10-5 8.81x10-6 7.44x10-5 5.29x10-5 toxoplasmosis 5 0 0 2.24x10-5 1.94x10-5 1.12x10-4 9.70x10-5 teniasis 3 X X 9.69x10-7 0.00 2.91x10-6 0.00 X - data not available
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e) to reheat cooked food thoroughly before RI consumption; 0,00035 f) to avoid the contact of raw and cooked food; 0,0003 g) to maintain sufficient personal hygiene during the 0,00025 preparation of food; 0,0002 h) to maintain the hygiene of working environment 0,00015 and tools during the preparation of food; 0,0001 i) to protect food against insects, rodents and other 0,00005 animals; 0 2003 2004 2005 2006 2007 2008 j) to use drinking water; The above mentioned preventive measures are of key intestinal infections, South Moravia Region intestinal infections, Czech Republic importance especially in summer season, which has all favourable conditions for the reproduction of causal agents of intestinal infections. Fig. 3 The development of individual risk RI of infection caused by intestinal infections in the region and the Czech Republic RI 0,005 0,004 5 Conclusion The individual risk R of infections caused by selected 0,003 I bacterial, viral and parasitic zoonoses of alimentary 0,002 origin has been assessed in the South Moravia region 0,001 and then compared with the country average. 0 Unacceptable risk has been recorded in case of 2003 2004 2005 2006 2007 2008 salmonellosis, campylobacteriosis and other bacterial intestinal infections, where the risk values exceed the campylobacteriosis, Czech Republic referential value R = 10-4 [peson-1.year-1] published by campylobacteriosis, South Moravia Region I the U.S. EPA. It is worth mentioning that the detection of infections, which is carried out by epidemiological- Fig. 1 The development of individual risk hygienic service, remains on a qualitatively very high of infection caused by campylobacteriosis in the region level in the Czech Republic. and the Czech Republic The risk situation in the region corresponds with exceptions with the situation in the whole Czech Republic. The situation in the region is less favourable in
RI case of critical infections, but on the contrary it is more favourable in case of low frequency diseases. Similar 0,0045 0,004 outcomes have been obtained also after incorporating the 0,0035 impacts of individual infections. 0,003 The development of risk situation did not change 0,0025 a lot from 2003 to 2008 and it slightly improves both in 0,002 0,0015 the Czech Republic and the region. Significantly 0,001 increased risk of infection caused by hepatitis A was 0,0005 monitored in 2008 together with the increasing 0 2003 2004 2005 2006 2007 2008 campylobacteriosis salmonellosis infections risk ratio. The outcomes have shown that attention has to be paid salmonellosis, South Moravia Region salmonellosis, Czech Republic mainly to the area of preventing the transport of campylobacteria, partially salmonella and lately mainly Fig. 2 The development of individual risk RI of infection hepatitis A. Specific measures have been proposed to caused by salmonellosis in the region and the Czech deal with the above mentioned infections. Republic
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[2] Collective of authors at SZÚ Alimentary diseases (infections and food poisoning). SZÚ Brno : 2005. 38 p. [3] STAŇKOVÁ, M., MAREŠOVÁ, V., VANIŠTA, J. Review manual of infectious diseases. Triton. 1st edit. Prague, 2008. 207 p. ISBN 978-80-7387- 056-0. [4] KLABAN, V. Illustrated microbiological dictionary. Galen. 1st edit. Prague, 2005. 654 p. ISBN 80-7262-341-9. [5] State Health Institute. Infections in the Czech Republic - EPIDAT. [on line]. [2009-03-13]. URL: http://www.szu.cz/data/infekce-v-cr. [6] Ministry of Health (MoH) of the Czech Republic. Act No 258/2000 Coll. On the protection of public health, as amended by the Act. Prague : MoH CZE, 2000. [7] Ministry of Health (MoH) of the Czech Republic. Decree No. 440/2000 Coll. which amends the conditions for the prevention of origin and spread of infectious diseases. Prague : MoH CZE, 2000. [8] BERÁNEK, Z. et al. Cleaner production. Prague : CCCP, 1996, p. 36. [9] Czech Statistical Institute. Population. Publication on population. [on line]. [2009-03-13]. URL: http://www.czso.cz/csu/edicniplan.nsf/select_obyv atelstvo. [10] VAVERKOVÁ, R. Personnel department. Brno : Regional hygienic centre, 2009. [11] U.S. EPA. Integrated Risk Information System (IRIS). Database of Toxicological Parameters for Human Health. [on line]. [2009-03-14]. URL:
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