Preventive measures, risk behaviour and the most common health problems in Czech travellers: a prospective questionnaire study in post-travel clinic outpatients.

OBJECTIVE:  The aim of this study was to evaluate attitudes towards the available preventive measures, risk behaviour and health problems in Czech travellers to tropical and subtropical regions. MATERIALS AND METHODS:  The prospective study included patients of all ages with a history of recent travel to risky countries who presented to the post-travel clinic of the Hospital Na Bulovce in Prague within two months after return, from February 2009 to June 2018. The data were collec-ted through a questionnaire survey and from electronic medical records. RESULTS:  Nine hundred and thirty-four patients (473 M and 461 F, age median of 32 years, IQR 27-39) participated in the study. The most frequent destinations were South-East Asia (332; 35.5%), South Asia (176, 18.8%), and Sub-Saharan Africa (172; 18.4%). The most common reasons for tra-vel were tourism (772; 82.7%) and business (111; 11.9%). An underlying chronic disease was reported by 317 patients (33.9%). Pre-travel health consultation was sought by 415 travellers (44.4%); however, only 312 (33.4%) of the respondents were properly vaccinated. Preventive malaria chemoprophylaxis was indicated in a total of 151 travellers (16.2%) but was only received by 44/151 patients (29.1%). Risky eating or drinking behaviour was admitted by 832 (89.1%) respondents and low standard accommodation by 525 (56.2 %) travellers. The most commonly reported clinical syndromes were acute and chronic diarrhoea (266; 28.5%), febrile illness (240; 25.7%) and skin lesions (166; 17.8%). A total of 199 patients presented with tropical infection (21.3%) and 63 with a vaccine-preventable infection or malaria (6.7%).  Conclusions: The study shows that the adherence of Czech travellers to preventive measures is relatively low, and along with risky behaviours, has a significant impact on travel-related morbidity. However, vaccine-preventable infections only accounted for a small fraction of travel-related illness, which is in accordance with other epidemiological studies and points out the need for a more comprehensive interdisciplinary approach to pre-travel health consultations.

Listeriosis - an analysis of human cases in the Czech Republic in 2008-2018.

AIM: The aim of our work was to summarize the most important knowledge about listeriosis in humans and to analyse available epidemiological data on this disease in the Czech Republic in 2008-2018. METHODS: We conducted a literature search and descriptive epidemiological analysis of all human Listeria cases reported to the national surveillance system of infectious diseases (EpiDat until 2017, ISIN for 2018) in the Czech Republic in 2008-2018. For data management and analysis, MS Excel 2010 was used. The incidence maps were created using the ECDC Map Maker tool (EMMa). RESULTS: In total, 380 cases of human listeriosis (mean annual incidence of 0.33/100 000 inhabitants) were reported in the Czech Republic in 2008-2018. The highest age specific incidence was detected in 0-year-olds (1.85/100 000) and then in persons over 60 years (mean incidence of 0.95/100 000). Altogether 222 cases were detected in men (mean incidence of 0.39/100 000) and 158 in women (mean incidence of 0.27/100 000). Geographically, the highest mean annual incidence was reported in the Moravian-Silesian Region (0.6/100 000) and Pilsen Region (0.57/100 000). As many as 96.3% of the reported cases required hospital admission. Of 81 deaths related to listeriosis, 50 were directly caused by listeriosis. The highest monthly incidence was observed in June through October and then in January.  The incidence of listeriosis in the CZ shows an oscillating trend over the last 11 years. Neither epidemics nor imported cases were reported to the national surveillance system during the study period. CONCLUSIONS: Listeriosis cases have been on the rise in the European Union (EU) over the last years, while in the CZ, an oscillating and slightly increasing trend has been observed. Generally, cases are reported mostly in the population aged over 64 years (and especially after the age of 84). As there is no vaccine available yet against this disease, the only option is the prevention, i.e., health education of consumers in general and of the risk groups in particular, and compliance with food safety and hygiene standards in food production and handling.

[Human alveolar echinococcosis and an overview of the occurrence of Echinococcus multilocularis in animals in the Czech Republic]. / Humánní alveolární echinokokóza a prehled výskytu tasemnic Echinococcus multilocularis u zvírat v Ceské republice.

Human alveolar echinococcosis (AE) is caused by larval stages of the tapeworm Echinococcus multilocularis. In the Czech Republic, screening tests to detect the specific infectious agent have been performed since 1998. The first AE cases were diagnosed in 2007, and until 2014, a total of 21 diseases were recorded. In accordance with radiological, histological, and/or PCR data, serological examinations of 699 individuals helped to reveal 15 additional AE cases in the period of 2015-2016. From the cumulative data for 1998-2016, it appears that of 2,695 patients examined, 36 (18 men and 18 women) were diagnosed with AE. Their age at diagnosis ranged from 20 to 82 years and was lower for women (mean 43.7, median 39.5) than for men (50.9 and 57.5, respectively), but the difference was not statistically significant. In the period of 2007-2016, the mean annual incidence rate was 0.034 cases/100 000 population. Our study indicates an ongoing increase in AE cases. The disease can be autochthonous in nature, as evidenced not only by some case history data but also by the detection of the larval stages in wild boar (Sus scrofa). AE risk to humans in the Czech Republic is discussed in the context of the known data on the presence of various parasite developmental stages in animals.

[Imported tropical infections]. / Importované tropické infekce.

The rising number of our tourists, who spend their holiday in tropical countries together with the rising immigration from the countries with low hygienic standard, increases the risk of import of some tropical infections. The most common are diarrhoeal diseases; to the more serious belong febrile infections (malaria, typhoid fever, ricketsioses), that without early treatment can be fatal. The diagnosis is based on the precise history, physical, laboratory and special microbiological examination. Among the laboratory methods of the first choice belong the thin smear, the thick blood film, blood count and differential counting, haemocultivation, and detection of inflammatory markers. Finding of the high eosinophilia suggests helmintosis (schistosomosis, filariosis, cystecerkosis, hydatiodosis). Though the tourists become better informed on the health risks during the stay in tropical countries, it is still possible to encounter persons living for high risk countries without proper vaccination and antimalarian prophylaxis.

[Hydatic cysts--echinococcosis]. / Echinokoková nákaza--echinococcosis.

The case diagnosis and treatment of hydatic cyst in the right and left lobe of the liver in a 28 year old pregnant woman is described in the article.

Pyruvate : NADP+ oxidoreductase from the mitochondrion of Euglena gracilis and from the apicomplexan Cryptosporidium parvum: a biochemical relic linking pyruvate metabolism in mitochondriate and amitochondriate protists.

Most eukaryotes perform the oxidative decarboxylation of pyruvate in mitochondria using pyruvate dehydrogenase (PDH). Eukaryotes that lack mitochondria also lack PDH, using instead the O(2)-sensitive enzyme pyruvate : ferredoxin oxidoreductase (PFO), which is localized either in the cytosol or in hydrogenosomes. The facultatively anaerobic mitochondria of the photosynthetic protist Euglena gracilis constitute a hitherto unique exception in that these mitochondria oxidize pyruvate with the O(2)-sensitive enzyme pyruvate : NADP oxidoreductase (PNO). Cloning and analysis of Euglena PNO revealed that the cDNA encodes a mitochondrial transit peptide followed by an N-terminal PFO domain that is fused to a C-terminal NADPH-cytochrome P450 reductase (CPR) domain. Two independent 5.8-kb full-size cDNAs for Euglena mitochondrial PNO were isolated; the gene was expressed in cultures supplied with 2% CO(2) in air and with 2% CO(2) in N(2). The apicomplexan Cryptosporidium parvum was also shown to encode and express the same PFO-CPR fusion, except that, unlike E. gracilis, no mitochondrial transit peptide for C. parvum PNO was found. Recombination-derived remnants of PNO are conserved in the genomes of Saccharomyces cerevisiae and Schizosaccharomyces pombe as proteins involved in sulfite reduction. Notably, Trypanosoma brucei was found to encode homologs of both PFO and all four PDH subunits. Gene organization and phylogeny revealed that eukaryotic nuclear genes for mitochondrial, hydrogenosomal, and cytosolic PFO trace to a single eubacterial acquisition. These findings suggest a common ancestry of PFO in amitochondriate protists with Euglena mitochondrial PNO and Cryptosporidium PNO. They are also consistent with the view that eukaryotic PFO domains are biochemical relics inherited from a facultatively anaerobic, eubacterial ancestor of mitochondria and hydrogenosomes.

The Azotobacter chroococcum hydrogenase gene cluster: sequences and genetic analysis of four accessory genes, hupA, hupB, hupY and hupC.

The Azotobacter chroococcum chromosome contains a region spanning about 14 kb associated with hydrogen-uptake (Hup) activity. The small and large subunits of the hydrogenase are encoded by the structural genes hupS and hupL. Two other genes, hupD and hupE, are located 8.9 kb downstream from hupL and are required for the formation of a catalytically active hydrogenase. In this study, we determined the nucleotide sequence of a 3.8-kb region immediately upstream from hupD. This revealed four additional closely linked ORFs which we designated hupA, hupB, hupY and hupC; these genes potentially encode polypeptides with predicted masses of 12.6, 33.3, 80.4 and 9.0 kDa, respectively. This cluster of genes was shown to be essential for hydrogenase activity by insertion mutagenesis using antibiotic-resistance gene cassettes and a Tn5 derivative carrying a promoterless lacZ gene. A 10.5-kb fragment of DNA beginning 3.4 kb downstream from hupL, and including the sequenced region, was able to complement hupA and hupY mutants, supporting earlier evidence for a promoter downstream from hupSL. The deduced amino acid sequences of hupA, hupB and hupC are homologous to the Escherichia coli hypA, hypB and hypC gene products, respectively. Of particular interest is the fact that there is no homologue of the hupY gene product in the E. coli hyp operon. Mutations in hupY or hupB had little effect on beta-galactosidase activity in a strain also carrying a hupL::lacZ fusion, showing that hupY and hupB are not major factors in regulating the transcription of the hydrogenase structural genes.

Characterization of two genes (hupD and hupE) required for hydrogenase activity in Azotobacter chroococcum.

In Azotobacter chroococcum the hydrogenase structural genes (hupSL) cover about 2.8 kb of a 15-kb region associated with hydrogen-uptake (Hup) activity. Two other genes in this region, hupD and hupE, were located 8.9 kb downstream of hupL and were shown to be essential for hydrogenase activity by insertion mutagenesis. A fragment of DNA beginning 3.4 kb downstream of hupL was able to complement the hupE mutant, supporting earlier evidence for a promoter downstream of hupSL. Hybridization experiments showed that hupD and hupE share some similarity with a region of Alcaligenes eutrophus DNA which is apparently involved in the formation of catalytically active hydrogenase. The hupD gene encodes a 379-amino acid, 41.4-kDa polypeptide while hupE codes for a 341-amino acid, 36.1-kDa product. The predicted amino acid sequences of the hupD and hupE genes are homologous to the Escherichia coli hypD and hypE gene products, respectively. A polar mutation in hupD had no effect on beta-galactosidase activity in a strain also carrying a hupL-lacZ fusion, indicating that hupD and hupE are probably not involved in regulating hydrogenase structural gene expression.

Sensitivity of some marine bacteria, a moderate halophile, and Escherichia coli to uncouplers at alkaline pH.

The inhibitory effects of uncouplers on amino acid transport into three marine bacteria, Vibrio alginolyticus 118, Vibrio parahaemolyticus 113, and Alteromonas haloplanktis 214, into a moderate halophile, Vibrio costicola NRC 37001, and into Escherichia coli K-12 were found to vary depending upon the uncoupler tested, its concentration, and the pH. Higher concentrations of all of the uncouplers were required to inhibit transport at pH 8.5 than at pH 7.0. The protonophore carbonyl cyanide m-chlorophenylhydrazone showed the greatest reduction in inhibitory capacity as the pH was increased, carbonyl cyanide p-trifluoromethoxyphenylhydrazone showed less reduction, and 3,3',4',5-tetrachlorosalicylanilide was almost as effective as an inhibitor of amino acid transport at pH 8.5 as at pH 7.0 for all of the organisms except A. haloplanktis 214. Differences between the protonophores in their relative activities at pHs 7.0 and 8.5 were attributed to differences in their pK values. 3,3',4',5-Tetrachlorosalicylanilide, carbonyl cyanide m-chlorophenylhydrazone, 2-heptyl-4-hydroxyquinoline-N-oxide, and NaCN all inhibited Na+ extrusion from Na+-loaded cells of V. alginolyticus 118 at pH 8.5. The results support the conclusion that Na+ extrusion from this organism at pH 8.5 occurs as a result of Na+/H+ antiport activity. Data are presented indicating the presence in V. alginolyticus 118 of an NADH oxidase which is stimulated by Na+ at pH 8.5.