Long-Term Monitoring of the Antibody Response to a SARS-CoV-2 Infection.

A group of 110 patients from the West Bohemian region who had been infected with COVID-19 was monitored for the purposes of this study. We focused on cases of mild or moderate COVID-19; statistically the most likely to occur. Day zero was defined as the day on which a positive PCR test was first established. The mean length of observation was 6.5 months, the maximum length 12 months. The first blood samples were taken from a smaller cohort during the 1-3 months following the first positive PCR test. We assumed that SARS-CoV-2 antibodies would be present during this period and therefore a limited number of samples were taken for the purpose of detecting antibodies. More samples were collected, starting 4 months after the first positive PCR test. A subsequent set of blood samples were drawn, mostly 6 months after the first ones. Our study confirmed the presence of total IgG SARS-CoV-2 antibodies up to 1 year after the onset of the disease. The peak of antibody production was observed in the third month after the first positive PCR test. A mathematical estimate of the median duration of antibody positivity was calculated to be 18 months from the onset of the COVID-19 infection.

Ten-year follow-up on efficacy, immunogenicity and safety of two doses of a combined measles-mumps-rubella-varicella vaccine or one dose of monovalent varicella vaccine: Results from five East European countries.

BACKGROUND: We assessed the 10-year efficacy, immunogenicity and safety of two doses of a combined measles-mumps-rubella-varicella vaccine (MMRV) or one dose of a monovalent varicella vaccine (V) in children from Czech Republic, Lithuania, Poland, Romania and Slovakia. METHODS: This was a phase IIIB follow-up of an observer-blind, randomized, controlled trial (NCT00226499). In phase A, healthy children aged 12-22 months from 10 European countries were randomized in a 3:3:1 ratio to receive two doses of MMRV (MMRV group), one dose of MMR followed by one dose of V (MMR + V group), or two doses of MMR (MMR; control group), 42 days apart. Vaccine efficacy (VE) against varicella (confirmed by viral DNA detection or epidemiological link and clinical assessment) was calculated with 95% confidence intervals using Cox proportional hazards regression model. Immunogenicity was assessed as seropositivity rates and geometric mean concentrations (GMCs). Solicited and unsolicited adverse events (AEs) and serious AEs (SAEs) were recorded. RESULTS: A total of 3705 children were vaccinated (1590, MMRV group; 1586, MMR + V group; 529, MMR group). There were 663 confirmed varicella cases (47, MMRV group; 349, MMR + V group; 267, MMR group). VE ranged between 95.4% (Lithuania) and 97.4% (Slovakia) in the MMRV group and between 59.3% (Lithuania) and 74% (Slovakia) in the MMR + V group. At year 10, seropositivity rates were 99.5%-100% in the MMRV group, 98%-100% in the MMR + V group and 50%-100% in the MMR control group, and the anti-VZV antibody GMCs were comparable between MMRV and MMR + V groups. The occurrence of solicited and unsolicited AEs was similar across groups and no SAE was considered as vaccination-related. No new safety concerns were identified. CONCLUSIONS: Our results indicated that two doses of varicella zoster virus-containing vaccine provided better protection than one dose against varicella and induced antibody responses that persisted 10 years post-vaccination.

Five Commercial Immunoassays for SARS-CoV-2 Antibody Determination and Their Comparison and Correlation with the Virus Neutralization Test.

There is an ongoing debate as to whether SARS-CoV-2 antibodies can be found in patients who have recovered from COVID-19 disease. Currently, there is no consensus on whether the antibodies, if present, are protective. Our regular measurements of SARS-CoV-2 antibodies, starting in July 2020, have provided us with the opportunity of becoming acquainted with the five different immunoassays. A total of 149 patients were enrolled in our study. We measured the samples using each immunoassay, then performing a virus neutralization test and comparing the results of SARS-CoV-2 antibodies with this test. We observed that the production of neutralizing antibodies is age-dependent. Elderly patients have a higher proportion of high neutralizing titers than young patients. Based on our results, and in combination with the literature findings, we can conclude that the serological SARS-CoV-2 antibody measurement is a helpful tool in the fight against COVID-19. The assays can provide information about the patient's previous contact with the virus. Anti-spike protein assays correlate well with the virus neutralization test and can be used in the screening of potential convalescent plasma donors.

One or two doses of live varicella virus-containing vaccines: Efficacy, persistence of immune responses, and safety six years after administration in healthy children during their second year of life.

BACKGROUND: This phase III B follow-up of an initial multicenter study (NCT00226499) will evaluate the ten-year efficacy of two doses of the combined measles-mumps-rubella-varicella vaccine (MMRV) and one dose of the live attenuated varicella vaccine (V) versus a measles-mumps-rubella control group (MMR) for the prevention of clinical varicella disease. Here we present efficacy results for six years post-vaccination. METHODS: In phase A of the study, healthy children aged 12-22 months from ten European countries were randomized (3:3:1) and received either two doses of MMRV, or one dose of combined MMR and one dose of monovalent varicella vaccine (MMR+V), or two doses of the MMR vaccine (control), 42 days apart. Vaccine efficacy against all and against moderate or severe varicella (confirmed by detection of viral DNA or epidemiological link) was assessed from six weeks up to six years post-dose 2 for the MMRV and MMR+V groups, and was calculated with 95% confidence intervals (CI). The severity of varicella was calculated using the modified Vázquez scale (mild ≤ 7; moderately severe = 8-15; severe ≥ 16). Herpes zoster cases were also recorded. RESULTS: 5289 children (MMRV = 2279, mean age = 14.2, standard deviation [SD] = 2.5; MMR+V = 2266, mean age = 14.2, SD = 2.4; MMR = 744, mean age = 14.2, SD = 2.5 months) were included in the efficacy cohort. 815 varicella cases were confirmed. Efficacy of two doses of MMRV against all and against moderate or severe varicella was 95.0% (95% CI: 93.6-96.2) and 99.0% (95% CI: 97.7-99.6), respectively. Efficacy of one dose of varicella vaccine against all and against moderate or severe varicella was 67.0% (95% CI: 61.8-71.4) and 90.3% (95% CI: 86.9-92.8), respectively. There were four confirmed herpes zoster cases (MMR+V = 2, MMR = 2), all were mild and three tested positive for the wild-type virus. CONCLUSIONS: Two doses of the MMRV vaccine and one dose of the varicella vaccine remain efficacious through six years post-vaccination.

Cost Burden of Severe Community-Acquired Rotavirus Gastroenteritis Requiring Hospitalization in the Czech Republic, Slovakia, Poland, and Hungary: A Retrospective Patient Chart Review.

OBJECTIVES: To provide valuable local data on the economic burden of rotavirus gastroenteritis (RVGE) for decision making on introduction of rotavirus vaccination in Central European countries. METHODS: We conducted a retrospective patient hospital chart review during the winter RVGE peak in the Czech Republic (n = 109), Hungary (n = 109), Poland, (n = 112), and Slovakia (n = 115) to estimate resource use and associated costs from the payer's perspective in children younger than 5 years with severe RVGE requiring hospitalization. Microcosting analysis was used to estimate the average costs of treating RVGE inpatients including pre- and posthospitalization costs. RESULTS: The average cost of treatment was €476, €316, €741, and €594 in the Czech Republic, Hungary, Poland, and Slovakia, respectively. Extrapolating these costs to the total number of RVGE hospitalizations gives annual cost estimates of €2.1 million, €1.5 million, €13.2 million, and €1.5 million, respectively. The main component of expenditure in all the four countries is the hospital stay, but wide variation among countries was observed (total cost of treating RVGE in hospital was almost 2.5-fold higher in Poland than in Hungary). In countries with diagnosis related group (DRG) costs available, the best agreement between real resource-use-driven costs and the DRG cost was found in the Czech Republic and Hungary, with differences of only €22 and €33, respectively. In Poland, the microcosting indicated higher overall costs incurred in hospital than the DRG cost, with a difference exceeding €190. CONCLUSIONS: Hospitalization of children with RVGE represents a substantial economic burden for the national health systems in these countries.

Surveillance of pneumococcal diseases in Central and Eastern Europe.

Pneumococcal infection is a major cause of morbidity and mortality worldwide. The burden of disease associated with S. pneumoniae is largely preventable through routine vaccination. Pneumococcal conjugate vaccines (e.g. PCV7, PCV13) provide protection from invasive pneumococcal disease as well as non-invasive infection (pneumonia, acute otitis media), and decrease vaccine-type nasopharyngeal colonisation, thus reducing transmission to unvaccinated individuals. PCVs have also been shown to reduce the incidence of antibiotic-resistant pneumococcal disease. Surveillance for pneumococcal disease is important to understand local epidemiology, serotype distribution and antibiotic resistance rates. Surveillance systems also help to inform policy development, including vaccine recommendations, and monitor the impact of pneumococcal vaccination. National pneumococcal surveillance systems exist in a number of countries in Central and Eastern Europe (such as Croatia, Czech Republic, Hungary, Poland, Romania and Slovakia), and some have introduced PCVs (Czech Republic, Hungary, Kazakhstan, Russia, Slovakia and Turkey). Those countries without established programs (such as Kazakhstan, Russia and Ukraine) may be able to learn from the experiences of those with national surveillance systems. The serotype distributions and impact of PCV13 on pediatric pneumococcal diseases are relatively similar in different parts of the world, suggesting that approaches to vaccination used elsewhere are also likely to be effective in Central and Eastern Europe. This article briefly reviews the epidemiology of pneumococcal disease, presents the latest surveillance data from Central and Eastern Europe, and discusses any similarities and differences in these data as well the potential implications for vaccination policies in the region.

Previous Vaccination and Age are More Important Predictors of Immune Response to Influenza Vaccine than Inflammation and Iron Status in Dialysis Patients.

BACKGROUND/AIMS: The immune response to influenza vaccine may be influenced by many factors, e.g. age, comorbidities or inflammation, and iron status. METHODS: We studied the vaccine-induced production of hemagglutination-inhibition antibodies (HI) in 133 hemodialysis patients (HD) and 40 controls. To identify variables associated with the immune response, uni- and multivariate regression analyses were performed with seroconversion in HI titers as a dependent variable, with demographics, comorbidities, previous vaccination, inflammation, and iron status as independent variables. RESULTS: Seroconversion rates were lower in HD than in controls [43% versus 73% (H1N1 strain; p < 0.05); 43% versus 53% (H3N2; P=NS); 36% versus 62% (B; p < 0.05)]. In both HD and control groups, the predictors of the inferior HI production were pre-vaccination seroprotection, vaccination in the previous season, and old age. We did not find associations between seroconversion rates and inflammation and iron status in the studied populations. This was also true for a subanalysis of patients without pre-vaccination seroprotection. CONCLUSION: The influenza vaccine-induced antibody production was lower in HD than in controls and was independent of inflammation and iron status in both groups. Besides dependence on dialysis, the variables associated with inferior seroconversion rates included pre-vaccination seroprotection, previous vaccination, and old age.

Safety and immunogenicity of an investigational vaccine containing two common pneumococcal proteins in toddlers: a phase II randomized clinical trial.

BACKGROUND: To provide broader protection against pneumococcal disease, new vaccines containing conserved Streptococcus pneumoniae proteins are being developed. This study assessed the safety, reactogenicity and immunogenicity of four formulations containing pneumococcal proteins pneumolysin toxoid (dPly) and histidine triad protein (PhtD) in toddlers. METHODS: In this phase II, multicenter, observer-blind study (www.clinicaltrials.gov: NCT00985751) conducted in the Czech Republic, toddlers (12-23 months) were randomized (1:1:1:1:1) to receive one of four investigational vaccine formulations (10 or 30µg each of dPly and PhtD, alone or in combination with polysaccharide conjugates from the pneumococcal non-typeable Haemophilus influenzae protein-D conjugate vaccine [PHiD-CV]), or the licensed PHiD-CV, in a 2-dose primary series plus booster at study months 0, 2 and 6. Solicited local and general symptoms were recorded within seven days post-vaccination, unsolicited symptoms within 31 days post-vaccination, and serious adverse events (SAEs) during the entire study period. Antibody concentrations against the vaccine components were measured pre-vaccination, one month post-dose 2, pre- and one month post-booster. RESULTS: 257 toddlers were enrolled and vaccinated. Percentages of solicited local and general symptoms following the different investigational formulations were generally within the same ranges as for PHiD-CV. After each dose, grade 3 fever (>40.0°C, rectal measurement) was reported for maximum one toddler in each group with no differences between investigational formulations and PHiD-CV during primary vaccination. 23 SAEs were reported for 17 toddlers, with distribution balanced between all groups except the group receiving 30 µg dPly/PhtD with PHiD-CV-conjugates (no SAEs reported). None of the SAEs were considered to be vaccine-related. For all pneumococcal protein-containing formulations, anti-PhtD and anti-Ply antibody geometric mean concentrations increased from pre-vaccination to post-dose 2 and from pre- to post-booster vaccination. CONCLUSION: All investigational vaccine formulations were well-tolerated and immunogenic when administered to toddlers as a 2-dose primary vaccination followed by a booster dose.

Rotavirus gastroenteritis in the Czech Republic before the start of vaccination.

BACKGROUND: The primary objective of our study was to investigate rotavirus gastroenteritis (RVGE) retrospectively in the Czech Republic (CzR) and try to estimate its significance in the most affected age groups in the prerotavirus vaccine era. METHODS: To analyze the epidemiological data on RVGE in the CzR, two databases were used retrospectively. The first database consisted of regular yearly reports from the laboratories diagnosing rotavirus infections from 1998 to 2006. The second database used was EPIDAT (the official notification system of the hygiene service). The data from 1998 to 2006 was analysed. RESULTS: From 1998 to 2006, the laboratories reported 1,430 to 4,815 cases of RVGE per year. By extrapolation--, in the CR in 2006, there were an estimated 4,076 rotavirus-related hospitalizations (696.7/100,000 in the age group < 5 years). The most commonly applied detection systems in 2006 were immunochromatography and latex agglutination. Of the RVGE cases recorded in the Epidat database between 1998-2006, 76.0-89.2% were for children aged less than five years. Seasonality was observed with the highest incidence rates between January and May with most cases usually occurring in March. Over nine years, there were six deaths linked directly to RVGE - three -deaths reported in children under two and three deaths reported in elderly people whose deaths were related to the epidemics in retirement homes. CONCLUSIONS: The estimated incidence rates of RVGE hospitalization in 2006 was higher in the CzR than that reported in other industrialized European countries. Our findings might verify the need for rotavirus vaccine implementation in the Czech Republic and reinforce the importance of rotavirus gastroenteritis surveillance.

Tick-borne encephalitis in children and adolescents in the Czech Republic between 1960 and 2007.

BACKGROUND: The Czech Republic ranks among the countries with the highest prevalence of tick-borne encephalitis worldwide. The region of West Bohemia has the second highest morbidity within the Czech Republic. METHODS: Between 1960 and 2007, laboratories confirmed 410 cases of tick-borne encephalitis in children and adolescents of West Bohemia. Available epidemiological data were analyzed. RESULTS: The highest incidence (per 100 000 population) was found in the group of 15-19 years for both genders (males: 6.2; females: 4.3). Data on the consumption of non-pasteurized milk were found in 5.4% of patients. The preschool age group showed its highest incidence in June and September, and the risk of infection for older children was in July and August. CONCLUSIONS: The current low coverage of vaccination leads to an insignificant improvement to the overall frequency of this disease.

Screening family and sexual contacts of HBsAg+ persons in the Pilsen region.

THE AIM OF THE STUDY: To detect HBsAg-positive persons and to offer their family and sexual contacts, after screening for viral hepatitis B (VHB) markers, free vaccination against the infection. MATERIAL AND METHODS: In collaboration with laboratories, all persons with confirmed HBsAg in the Pilsen Region (549,618 population) were prospectively detected. From these persons, the following data were collected: reason for examination, clinical diagnosis, and ethnicity/nationality. Their family and sexual contacts were screened for serologic markers (HBsAg, anti-HBc, anti-HBs) and vaccinated. RESULTS: Between 1997-2005, 1,053 HBsAg+ persons were routinely detected by the laboratories in the Pilsen Region. The average age of the infected persons was 41.7 years (range 0-90 years). At the time of the detection, 63.4% of the HBsAg positives were clinically "healthy" carriers. Within the monitored period there was a considerable increase in the HBsAg positivity rate among immigrants (particularly from Vietnam). Of 908 family and sexual contacts, 18% were positive for hepatitis B markers. The highest seropositivity rates (33.9% and 27.7%) were found in siblings and parents, respectively, of the HBsAg+ persons. So far 77.5% of the susceptible contacts have used the opportunity for free vaccination. CONCLUSION: The study has proven the importance of detecting HBsAg carriers and vaccinating their contacts. Special attention should be paid to immigrant families, particularly from Asia. Consistent vaccination of family and sexual contacts of HBsAg+ persons can contribute to a more rapid elimination of hepatitis B in the Czech Republic.

Growth factors and breast tumors, comparison of selected growth factors with traditional tumor markers.

BACKGROUND: The first aim of this project was to study new possibilities for distinguishing benign from malignant tumors using growth factors and to compare them with the traditional tumor markers Carcinoembryonic antigen (CEA) and Cancer antigen 15-3 (CA15-3) for breast tumors. The second aim was to make a comparison of CEA, CA 15-3, Insulin-like growth factor I (IGF1), Insulin-like growth factor-binding protein 3 (IGFBP3), Hepatocyte growth factor (HGF) and Epidermal growth factor (EGF) for individual stages of cancer. PATIENTS AND METHODS: Our group of patients consisted of 110 females, 89 with breast cancer and 21 with benign breast tumors (fibroadenomas). Serum levels of CEA and CA 15-3 were measured using a DxI instrument. Serum levels of IGF1 and IGFBP3 were measured using IRMA radioisotope assay kits. HGF and EGF were measured using an xMAP Luminex multiplex panel. Serum samples were collected prior to surgery and those of the two groups of patients were compared (malign vs. benign). Patients with diabetes mellitus were excluded from this project. RESULTS AND DISCUSSION: Comparing the individual parameters of serum levels between the two groups of patients (malignant vs. benign) only HGF was found to show a statistically significant difference. The mean of HGF in patients with malignant diseases prior to surgery was 3370 pg/ml compared to 1799 pg/ml in benign tumors with p=0.0016. We found significantly lower serum values of IGF1 at stage III in comparison to stages I and II: mean values: at stage I=181 ng/ml, at stage II=182 ng/ml and at stage III=70 ng/ml; stage III vs. stage II, p=0.0167. CONCLUSION: Tumor markers are currently used for therapy monitoring in cancer patients as one of the indicators of successful therapy. Our findings correspond to existing literature. IGF1 and its binding protein IGFBP3 cannot be used to distinguish between malignant and benign tumor. HGF is considered to be a marker of progression and of the aggressiveness of breast cancer; our data fully corresponds to this. Based on our data, this marker could potentially be used as an additional tool for the differentiation between benign and malignant tumor.

Vitamin D in colorectal, breast, prostate and lung cancer: a pilot study.

BACKGROUND: Many studies have demonstrated the relationship between vitamin D and cancer of many different sites, including of the breast, colorectum, prostate and lung. Most epidemiological studies have assessed the effects of dietary intake only, although endogenous production after sun exposure is the main source of vitamin D. The aim of our pilot study was to study serum levels of vitamin D in general population and in patients with different type of cancer. PATIENTS AND METHODS: The control group consisted of 214 healthy individuals. Pathological groups of patients included 170 patients with different cancer types (28 patients with prostate cancer, 43 patients with breast cancer, 49 patients with colorectal cancer and 50 patients with lung cancer). All of the patients were enrolled in the early clinical stage of cancer up to clinical stage III. Advanced stages were not included into the study. Vitamin D serum levels were measured using ECLIA Roche method. RESULTS: All the results for serum vitamin D from pathological groups were significantly lower compared to the levels of the control group. All the cancer types had a high incidence rate of very low serum levels of vitamin D. Lung cancer had the highest incidence rate of very low vitamin D serum levels. CONCLUSION: We found a high incidence of hypovitaminosis D in cancer patients compared to a healthy control group among a Czech population. This incidence rate is higher in comparison to data found in literature from the other parts of the world. Based on the data from this study, a large epidemiological study monitoring vitamin D serum levels in the healthy population and in cancer patients in the Czech Republic has been already proposed.

Primary care-based surveillance to estimate the burden of rotavirus gastroenteritis among children aged less than 5 years in six European countries.

This observational, prospective study was undertaken to estimate the burden of rotavirus (RV) gastroenteritis (GE) leading to general practitioner (GP)/family paediatrician (FP) visits among children aged <5 years in Czech Republic, Germany, Italy, Poland, Spain and the UK. Children aged <5 years presenting with acute GE provided stool samples for rapid RV testing. RV+ samples were confirmed and typed by RT-PCR. Demographic and clinical data were collected for all RVGE episodes. Transmission patterns among other household children aged <5 years were also assessed. From November 2005 to May 2007, excluding data from the UK, 497/3,813 (13.0%) children aged <5 years presenting with acute GE to GP/FP and tested were RV+ by PCR. Most RVGE cases (69.1%) occurred in children aged <2 years, occurred between December and May (93.1%) and were moderate or severe by Vesikari score (92.9%). RV strain distribution varied between countries: G9P[8] was the most common type in Poland (54/76) and Spain (172/196), G1P[8] was predominant in the Czech Republic (56/64) and Italy (46/107), and G4P[8] and G1P[8] both prevailed in Germany (17/54 and 13/54, respectively). A total of 24/122 (19.7%) children aged <5 years resident in the same household as a PCR+ study participant also developed RVGE. Conclusion. This multinational epidemiological study in Europe shows that RV is easily transmitted among household children, with RVGE burden highest among children aged <2 years accessing primary healthcare for acute GE.

High ferritin, but not hepcidin, is associated with a poor immune response to an influenza vaccine in hemodialysis patients.

BACKGROUND: The immune response to vaccination in hemodialysis (HD) patients can be influenced by disorders of iron metabolism, iron overload or chronic inflammatory state. Elevated levels of hepcidin are considered a new marker of iron metabolism impairment and anemia of inflammation in HD patients. METHODS: We studied the effects of hepcidin, other markers of iron status and intravenous iron (Fe(iv)) on the response to an influenza vaccine (Influvac(R) subunit 2008/2009) in 40 HD patients. The immune response of HD patients was compared with that of 46 controls without renal disease according to serum antihemagglutinin antibody titer (anti-HA). RESULTS: A total of 31 HD patients (responders) attained seroconversion (at least a 4-fold increase in anti-HA) to at least 1 of 3 vaccine strains; 9 patients (nonresponders) did not respond to any strain. Responders did not differ from nonresponders in hepcidin [99 microg/l (36-200) vs. 97 microg/l (23-216), p = 0.97]. Responders had lower ferritin (571 +/- 291 vs. 821 +/- 309 microg/l, p = 0.031) and were administered higher doses of Fe(iv) within the last 12 weeks prior to vaccination [625 mg (312-625) vs. 312 mg (0-625), p = 0.029]. The seroconversion to A(H1N1), A(H3N2) and B strains was noted in 20, 52 and 40% of HD and in 11, 39 and 48% of controls, respectively (HD vs. controls, p = nonsignificant). The rates of seroprotection (anti-HA > or =40) to vaccine strains in HD (27, 85 and 95%) and controls (24, 96 and 98%) were also comparable. CONCLUSION: Antibody production following influenza vaccination in HD patients may be suppressed by very high ferritin levels. Hepcidin does not correlate with immune response and high levels of hepcidin may reflect its retention in HD patients. Fe(iv) administration was not associated with a poorer immune response. The immunogenicity of the A(H1N1) strain was inadequate in HD patients and controls alike.

Spatio-temporal variation of tick-borne encephalitis (TBE) incidence in the Czech Republic: is the current explanation of the disease's rise satisfactory?

A marked increase in tick-borne encephalitis (TBE) incidence has been observed in Europe during the last 2 decades. Hypothetical causes include global climatic fluctuations, human-induced environmental changes, and socio-economic changes. These factors are thought to be disproportionately relevant in different geographical areas. To date, epidemiological studies of this phenomenon were based primarily on aggregated data, and little is known about TBE dynamics on the detailed geographical scale. This study is aimed at the subregional variations of incidence of TBE in the Czech Republic. The methodology of spatial statistics was applied. Over 13,000 cases of TBE, registered 1971-2007, were pinpointed on a GIS map and analysed for density variations in both time and space. Selected areas were studied in detail, using time series analysis. These analyses revealed that the incidence of TBE was highly variable both across the country and over the study period. Although the aggregate total of reported cases were generally increasing, local trends were divergent. A detailed study of one endemic area (that one with the highest case density level) showed that heterogeneities are detectable, even on a very fine geographical scale. There was no evident spatial coherence of the TBE trends; and some adjacent areas showed quite differing trends. However, countrywide coherence was demonstrated for quasi-octennial fluctuations in the TBE series, associable with the North Atlantic oscillation. The possible influences of both various climatic and population covariates upon TBE occurrence are discussed. However, the geographical heterogeneity of the disease trends, at such a fine spatial scale, cannot be explained satisfactorily by fluctuations in climatic or socio-economic conditions.

Epidemiology of Helicobacter pylori infection in asymptomatic children: a prospective population-based study from the Czech Republic. Application of a monoclonal-based antigen-in-stool enzyme immunoassay.

BACKGROUND: Acquisition of Helicobacter pylori occurs mainly in childhood and is significantly influenced by geographical variations. The aim of this study is to evaluate the prevalence of H. pylori infection in a population-based sample of asymptomatic children in the Czech Republic. Furthermore, this study aims to identify potential risk factors associated with this infection. MATERIALS AND METHODS: A prospective, cross-sectional, population-based study was undertaken in 1545 asymptomatic Czech children (aged 0-15 years; male 49.3%). Active H. pylori infection was diagnosed by monoclonal antibody-based antigen-in-stool enzyme immunoassay. Socio-demographic details of each subject were analyzed using a self-administered standardized questionnaire. Multiple regression analysis was performed. RESULTS: Overall, 7.1% of asymptomatic children were diagnosed with H. pylori infection. Of the infected children, 5.8% lived in the general population. A positive association was found with increasing age, although not with gender. Independent risk factors associated with H. pylori infection in our pediatric population were: the number of children in a household (odds ratio [OR] 4.26; confidence interval [CI] 1.91-9.80); lack of formal education of fathers (OR 0.23; CI 0.18-0.64) and institutionalized children (OR 6.33; CI 2.25-26.50). CONCLUSIONS: This study of a large cohort of children demonstrated that, independent of gender, H. pylori infection in the Czech Republic is among the lowest reported in Europe. Socioeconomically disadvantaged children, unfortunately, are still at risk of harboring this potentially preventable infection in this low-prevalence region.

The prevalence of tick-borne encephalitis in the region of West Bohemia (Czech Republic) between 1960-2005.

Between 1960-2005, 1,621 cases of tick-borne encephalitis were confirmed by laboratory testing in the region of West Bohemia (now the regions of Pilsen and Karlovy Vary) which represents a rate of infection of 4.1 per 100,000 inhabitants per year. The highest infection rate was established in men aged 20-24 and women aged 45-54. Over the monitored years, there was a significant shift of the maximum infection rate into an older age group. Currently, it is the 45-64 age group which carries the highest rate of infection. Of the identified disease cases, 12 were lethal, which represents 0.7% of the total. Over the years, the risks of transmission in particular areas of the region have changed. The highest infection rate is currently in the district of Klatovy (21.7 per 100,000 inhabitants per year). Of the total number, only two cases were contracted outside the Czech Republic (Slovakia and Austria). In 4.8% cases, the patient's anamnesis showed data on the consumption of non-pasteurized milk. 3.0% of infections probably originated as a result of professional exposure. Over the years, the season of infection has extended. Presently, the transmission can occur anytime between March and November. According to official data, only 6.7% of the population in the Pilsen district has been vaccinated so far. The low percentage of vaccinated cases may, however, in no way influence the unfavorable epidemiological situation regarding tick-borne encephalitis.