Trends and risk factors of hepatitis A in Catalonia after the introduction of a hepatitis A+B vaccination programme.

At the end of 1998, universal hepatitis A+B vaccination of 12 year olds was introduced in Catalonia. The aim was to examine trends in hepatitis A during 2005-2015 and assess risk factors by age group. We carried out an observational epidemiological study of the incidence and risk factors of hepatitis A reported to the surveillance system. Information on exposure was recorded for each case for the 2-6 weeks before symptom onset. Spearman's coefficient was used to evaluate the trends of rates. The chi-square test was used to compare categorical. We studied 2621 hepatitis A cases; the age mean was 26.6 years (SD=18.2), and >50% of cases were in the 20-49 years age group. The incidence decreased from 3.28/100 000 in 2005 to 1.50/100 000 in 2015. The rate for women decreased over time (P = .008), but the reduction was not significant in men (P = .234). Men consistently had higher rates than women with the biggest difference being in the 20-34 years age group (rate 8.8 vs 2.8). The greatest risk factor was travel to an endemic country (42.1%) in the 0-19 years age group and male-to-male sexual contact (18.6%) in the 20-49 years age group. The case fatality rate in adults aged >49 years was 0.4%. In conclusion, the vaccination programme of preadolescents resulted in a reduction in hepatitis A cases. However, a significant amount of cases still appear in immigrants and men who have sex with men. Hepatitis A in adults is an emerging health problem that will require new strategies.

Improvement in the detection of enteric protozoa from clinical stool samples using the automated urine sediment analyzer sediMAX® 2 compared to sediMAX® 1.

Detection of intestinal parasites from fecal samples is routinely performed by direct wet mount examination. This method requires skilled personnel, and it is time consuming. The aim of this work is to demonstrate the usefulness of the newer automated urinary sediment analyser sediMAX 2 for a fast detection of intestinal protozoa in stool samples. A total of 700 consecutively preserved samples consisting of 70 positives and 630 negatives were analyzed. SediMAX 2 takes digital images of each sediment sample, and analysis was conducted using a dilution of stool specimens, allowing determination of typical morphology. Compared to manual microscopy, sediMAX 2 showed sensitivity and specificity of 100 % in the detection of intestinal parasites, as also recently demonstrated for sediMAX 1. However, all clinically important human protozoa were detected using only 15 images for each specimen, compared to 30 images required in sediMAX 1 analysis. Moreover, changing manually the focus, it is possible to carry out a discrimination between morphologically identical Entamoeba complex members, including the pathogenic E. histolytica and the non-pathogenic E. dispar, E. moshkovskii and E. Bangladeshi, from the non-pathogenic Entamoeba coli based on the number of nuclei present in the cells. This study presents sediMAX 2 as an automatic aid to traditional microscopy.

Reducing time to identification of aerobic bacteria and fastidious micro-organisms in positive blood cultures.

Rapid and early identification of micro-organisms in blood has a key role in the diagnosis of a febrile patient, in particular, in guiding the clinician to define the correct antibiotic therapy. This study presents a simple and very fast method with high performances for identifying bacteria by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) after only 4 h of incubation. We used early bacterial growth on PolyViteX chocolate agar plates inoculated with five drops of blood-broth medium deposited in the same point and spread with a sterile loop, followed by a direct transfer procedure on MALDI-TOF MS target slides without additional modification. Ninety-nine percentage of aerobic bacteria were correctly identified from 600 monomicrobial-positive blood cultures. This procedure allowed obtaining the correct identification of fastidious pathogens, such as Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae that need complex nutritional and environmental requirements in order to grow. Compared to the traditional pathogen identification from blood cultures that takes over 24 h, the reliability of results, rapid performance and suitability of this protocol allowed a more rapid administration of optimal antimicrobial treatment in the patients. SIGNIFICANCE AND IMPACT OF THE STUDY: Bloodstream infections are serious conditions with a high mortality and morbidity rate. Rapid identification of pathogens and appropriate antimicrobial therapy have a key role for successful patient outcome. In this work, we developed a rapid, simplified, accurate, and efficient method, reaching 99 % identification of aerobic bacteria from monomicrobial-positive blood cultures by using early growth on enriched medium, direct transfer to target plate without additional procedures, matrix-assisted laser desorption ionization-time of flight mass spectrometry and SARAMIS database. The application of this protocol allows to anticipate appropriate antibiotic therapy.

Effectiveness of acellular pertussis vaccination during childhood (<7 years of age) for preventing pertussis in household contacts 1-9 years old in Catalonia and Navarra (Spain).

Pertussis vaccination with 4-5 doses of acellular vaccines is recommended in Spain to all children at 2 months to 6 years of age. The effectiveness of the acellular pertussis vaccination was assessed in this study by comparing the incidence of secondary pertussis in vaccinated (4-5 doses) and unvaccinated or partially vaccinated (0-3 doses) household contacts 1-9 years old of confirmed cases of pertussis in Spain in 2012-13. Eighty-five percent of contacts had been vaccinated with 4-5 doses of acellular pertussis vaccines. During the 2-year study period, 64 cases of secondary pertussis were detected among 405 household contacts 1-9 years old: 47 among vaccinated and 17 among unvaccinated or partially vaccinated contacts. The effectiveness for preventing secondary pertussis, calculated as 1 minus the relative risk (RR) of secondary pertussis in vaccinated vs. unvaccinated/partially vaccinated contacts, was 50 % [95 % confidence interval (CI): 19-69 %, p < 0.01] when household contacts were vaccinated using DTaP, Tdap, hexavalent or heptavalent vaccines, and it was 51.3 % (95 % CI: 21-70 %, p < 0.01) when they were vaccinated using DTaP or TdaP vaccines. The effectiveness adjusted for age, sex, pertussis chemotherapy and type of household contact was 58.6 % (95 % CI: 17-79 %, p < 0.05) when contacts were vaccinated using available acellular vaccines, and it was 59.6 % (95 % CI: 18-80 %, p < 0.01) when they were vaccinated using DTaP vaccines. Acellular pertussis vaccination during childhood was effective for preventing secondary pertussis in household contacts 1-9 years old of pertussis cases in Catalonia and Navarra, Spain.

Detection of intestinal parasites by use of the cuvette-based automated microscopy analyser sediMAX(®).

Microscopy is the reference method for intestinal parasite identification. The cuvette-based automated microscopy analyser, sediMAX 1, provides 15 digital images of each sediment sample. In this study, we have evaluated this fully automated instrument for detection of enteric parasites, helminths and protozoa. A total of 700 consecutively preserved samples consisting of 60 positive samples (50 protozoa, ten helminths) and 640 negative samples were analysed. Operators were blinded to each others' results. Samples were randomized and were tested both by manual microscopy and sediMAX 1 for parasite recognition. The sediMAX 1 analysis was conducted using a dilution of faecal samples, allowing determination of morphology. The data obtained using sediMAX 1 showed a specificity of 100% and a sensitivity of 100%. Some species of helminths, such as Enterobius vermicularis, Strongyloides stercolaris, the Ancylostoma duodenale/Necator americanus complex, and schistosomes were not considered in this work, because they are rare in stool specimens, are not easily detectable with microscopy analysis, and require specific recovery techniques. This study demonstrated for the first time that sediMAX 1 can be an aid in enteric parasite identification.

High incidence of norovirus GII.4 outbreaks in hospitals and nursing homes in Catalonia (Spain), 2010-2011.

A descriptive study was performed between 1 January 2010 and 31 December 2011 to estimate the incidence of norovirus outbreaks in hospitals and nursing homes in Catalonia (Spain). Epidemiological surveys were done for each outbreak. Norovirus was confirmed using RT-PCR. The incidence of outbreaks/106 person-years by centre, and the attack rate, were calculated. Statistically significant differences were calculated using odds ratio (ORs) and 95% confidence intervals (CIs). Person-to-person transmission was responsible for 81·5% (22/27) of outbreaks. The incidence in the population was 156·7 outbreaks/106 person-years. The incidence by centre was 1·3% per year and was greater in hospitals (2·6%) than in nursing homes (0·9%) (OR 3·2, 95% CI 1·5-6·9). The global attack rate in residents and staff was 34·7% (816/2348). The mortality rate was 0·25% (2/816). Genogroup GII.4 caused 66·7% of outbreaks. Norovirus GII.4 outbreaks cause significant morbidity affecting both patients and staff.

Cases of acute gastroenteritis due to calicivirus in outbreaks: clinical differences by age and aetiological agent.

The Caliciviridae family includes norovirus and sapovirus, which both cause acute gastroenteritis (AGE). Currently, norovirus is the most common cause of AGE in all age groups in many countries. We analysed clinical differences in reported cases of acute gastroenteritis caused by caliciviruses (AGC) by age group and agent involved. We conducted a descriptive study of AGE outbreaks reported to the Public Health Agency of Catalonia (Spain) in 2010 and 2011. The odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to estimate the association between clinical symptoms and age. Clinical differences between the <15 years and ≥15 years age groups were statistically significant: children more frequently presented with vomiting (OR, 3.25; 95% CI, 2.56-4.13), abdominal pain (OR, 3.27; 95% CI, 2.60-4.12), fever (OR, 1.51; 95% CI, 1.17-1.96) and nausea (OR, 1.49; 95% CI, 1.19-1.85). Comparing clinical manifestations of sapovirus and norovirus infection in children aged <15 years, cases caused by norovirus more frequently presented with vomiting and fever (p <0.001), and cases caused by sapovirus more frequently presented with diarrhoea (p 0.013). Determination of the clinical differences associated with cases in outbreaks according to the age of the majority of cases and the symptoms most frequently detected may aid decision making and guide aetiological investigations and the adoption of prevention and control measures.

Norovirus: a growing cause of gastroenteritis in catalonia (Spain)?

Infectious acute gastroenteritis (AGE) is a major health problem worldwide. Salmonella is a leading cause of AGE outbreaks, but viruses may be responsible for up to 80% of cases. We compared the frequency and characteristics of AGE out breaks in Catalonia due to norovirus and Salmonella and the changes in these outbreaks from 2000 through 2010. In 2006 through 2010, we also investigated the distribution by season, setting, and implicated food, the incidence rates of cases associated, and the hospitalization rates. Differences in proportions were estimated by Pearson's chi-square test, and the odds ratio (OR) and 95% confidence interval (CI) were calculated. In 2000 through 2010, the number of AGE outbreaks caused by Salmonella decreased and those caused by norovirus significantly increased. From 2006 onward, norovirus was the most common etiology in AGE outbreaks, but in foodborne outbreaks, Salmonella was the more common cause until 2010. The incidence rate per 10(5) inhabitants was greater for norovirus (20.81 versus 3.97, P < 0.001), and the hospitalization rate was lower for norovirus (0.84 versus 4.69, P < 0.001). Salmonella infections occurred more frequently in the warmer months, and norovirus infections were more common in the colder months, both in terms of total outbreaks (OR = 4.50; 95% CI, 2.85 to 7.11; P < 0.001) and foodborne outbreaks (OR = 4.38; 95% CI, 2.42 to 7.95; P < 0.001). Norovirus infections were less common in private homes (OR = 0.08; 95% CI, 0.04 to 0.14; P < 0.001) and more common in nursing homes (P < 0.001) and hospitals or long-term care facilities (OR = 14.09; 95% CI, 3.35 to 59.33; P < 0.001). Foods most frequently implicated in norovirus infection outbreaks were seafood (22% ; OR = 7.89; 95% CI, 2.59 to 24.3; P < 0.001), and those most common in Salmonella infection outbreaks were mayonnaise and similar items (30.2%; OR = 0.05; 95% CI, 0.01 to 0.22; P < 0.001). Foodborne outbreaks in which the vehicle was not identified were more frequent in cases of norovirus infection (OR = 4.59; 95% CI, 2.54 to 8.30; P < 0.001). Our results indicate that norovirus rather than Salmonella is the most common cause of AGE outbreaks in Catalonia. Foodborne AGE outbreaks were more commonly caused by norovirus than by Salmonella only in 2010, the last year of the study.

Cost-effectiveness of rifampin for 4 months and isoniazid for 9 months in the treatment of tuberculosis infection.

The purpose of this study was to evaluate the cost-effectiveness of the strategy of controlling the contacts of tuberculosis patients with latent tuberculosis infection by means of treatment with rifampin for 4 months or isoniazid for 9 months. The cost was the sum of the cost of treating latent tuberculosis infection in all contacts plus the cost of treating tuberculosis in whom the disease was not avoided. The effectiveness was expressed as cases avoided. The efficacy adopted was 90 % for rifampin for 4 months and 93 % for isoniazid for 9 months. We carried out a sensitivity analysis for efficacies of rifampin for 4 months of 80 %, 75 %, 69 % and 65 %. Of the 1,002 patients studied, 139 were treated with rifampin for 4 months and 863 were treated with isoniazid for 9 months. The cost-effectiveness was 436,842.83/50 cases avoided with rifampin for 4 months and 692,164.42/40 cases avoided with isoniazid for 9 months. Rifampin for 4 months was dominant. In the sensitivity analysis, rifampin for 4 months was dominant for efficacies of 75 % or greater. The cost-effectiveness analysis favoured the use of rifampin for 4 months when its efficacy was 75 % or greater.

Is isoniazid for 6 months more cost-effective than isoniazid for 9 months?

SETTING: The optimal treatment for latent tuberculosis infection consists of isoniazid (H, INH) for 9-12 months. Although INH for 6 months (6H) is more cost-effective than the 12-month regimen, the cost-effectiveness of the 6H regimen and that of INH for 9 months (9H) have not been compared. OBJECTIVE: To compare the cost-effectiveness of treatment with 6H and 9H. METHODS: Cost-effectiveness was evaluated using the ratio of the cost of preventing one tuberculosis case using 6H vs. 9H. The cost was estimated as the product of the number of patients to be treated to prevent one case using 6H or 9H × the cost of 6H or 9H. RESULTS: A total of 1039 patients were studied. The number of patients that needed to be treated to prevent one case was 33 (95%CI 21-83) using 6H and 26 (95%CI 18-50) using 9H. The cost of 6H and 9H was respectively €444.34 and €578.26, and the cost ratio of preventing one case with 6H/9H was 0.98 (95%CI 0.6-1.5). CONCLUSIONS: The cost-effectiveness of treatment with 6H and 9H is similar.

Utility of clinical-epidemiological profiles in outbreaks of foodborne disease, Catalonia, 2002 through 2006.

The objective of this study was to evaluate the use of clinical-epidemiological profiles for classifying non-laboratory-confirmed outbreaks of foodborne disease (FBD) in Catalonia between 2002 and 2006 and for elucidating associations among factors contributing to these outbreaks. A total of 275 nonfamily outbreaks were studied, of which 190 (69.1%) were laboratory confirmed and 85 (30.9%) were not. In 176 (92.6%) of laboratory-confirmed outbreaks and 69 (81.2%) of non-laboratory-confirmed outbreaks, information was obtained on contributing factors (P = 0.009). In 72% of non-laboratory-confirmed outbreaks, the etiology was assigned by using clinical-epidemiological profiles; thus, 93% of outbreaks eventually were associated with an etiology. In laboratory-confirmed outbreaks, poor personal hygiene was positively associated with norovirus (odds ratio [OR], 2.69; 95% confidence interval [CI], 1.47 to 4.89; P = 0.0007) and negatively associated with Salmonella and Campylobacter (OR, 0.54; 95% CI, 0.33 to 0.89; P = 0.01), and an unsafe source was positively associated with Salmonella and Campylobacter (OR, 4.07; 95% CI, 1.72 to 10.09; P = 0.001) and negatively associated with norovirus (OR, 0.14; 95% CI, 0.04 to 0.58; P = 0.001). No differences were found among contributing factors associated with outbreaks with a laboratory-confirmed etiology and those associated with outbreaks with an etiology assigned according to the clinical-epidemiological profiles. Clinical-epidemiological profiles are useful for determining what prevention and control strategies are appropriate to the agents involved in each community and for designing outbreak investigations.

Epidemiological and clinical features of norovirus gastroenteritis in outbreaks: a population-based study.

Noroviruses are the most frequent cause of acute gastroenteritis in the community. In Catalonia, it is not clear how this type of viral gastroenteritis is evolving, and the objective of this prospective population-based study was to describe the incidence and epidemiological and clinical features of outbreaks of acute gastroenteritis due to norovirus in Catalonia between October 2004 and October 2005. Incidence rates were calculated using the estimated population of Catalonia in 2005. For each outbreak, the mode of transmission, the number of persons affected, demographic variables, clinical presentation, the date and time of onset of symptoms and the duration of symptoms, physician visits and hospitalizations were collected. Sixty viral outbreaks affecting 1791 people were identified, with no distinct seasonality. The mean number of outbreaks per month was 4.6. The global incidence was 24.6 per 100 000 person-years. The incidence was higher in women (25.7 per 100 000 person-years) and in the 5-11 years (52.4 per 100 000 person-years) and > or =65 years (42.4 per 100 000 person-years) age groups. The prevalence of vomiting, abdominal pain and general malaise was higher in children and adolescents, whereas the prevalence of diarrhoea and myalgia was higher in adults. These results suggest that norovirus infection has an important public health impact in Catalonia and that prevention strategies should be designed and implemented.

Differential features of foodborne gastroenteritis outbreaks of known and unknown etiology.

Foodborne diseases (FBD) are a major cause of disease and death, but their etiologies are not always known. Factors associated with determination of the etiologic agent of FBD outbreaks reported to the Department of Health in Catalonia (Spain) during 2002 to 2005 were studied. For each outbreak, the year, number of persons affected, hospitalization, and availability of samples from patients, food handlers, and foods were collected. The delay between the date of onset of symptoms of the second case and the report to the surveillance unit was calculated. The relationship between explanatory variables and determination of the cause of each outbreak was studied by logistic regression. The causal agent was identified in 242 (73.3%) of 330 outbreaks. Factors associated with determining the etiologic agent of the outbreak in the univariate analysis were availability of samples from cases (odd ratio [OR] of 6.0, 95% confidence interval [CI] of 3.2 to 11.1), hospitalization (OR of 5.1, 95% CI of 2.6 to 11.1), availability of samples from food handlers (OR of 2.7, 95% CI of 1.6 to 4.5), size > or = 10 cases (OR of 2.2, 95% CI of 1.3 to 3.2), availability of samples from food (OR of 1.8, 95% CI of 1.1 to 3.0), and the last year (2005) of the study period (OR of 1.9, 95% CI of 1.0 to 3.6). In the multivariate analysis, hospitalization (adjusted OR of 5.1, 95% CI of 2.4 to 11.2), size > or = 10 cases (adjusted OR of 2.1, 95% CI of 1.2 to 3.7), and the year 2005 (OR of 2.1, 95% CI of 1.1 to 4.0) remained associated. Collection and processing of clinical samples from cases and appropriate laboratory diagnoses of all possible etiologies of FBD, including viruses, are very important. Efforts by physicians and public health services to coordinate and improve their activity in these areas may help provide more accurate knowledge concerning the etiologies of FBD outbreaks and lead to more effective preventive procedures.

Foodborne outbreak of gastroenteritis due to Norovirus and Vibrio parahaemolyticus.

Vibrio parahaemolyticus and Norovirus have been recognized as the cause of sporadic cases or outbreaks of diarrhoeal illness in association with the ingestion of raw or improperly cooked seafood. This report describes a foodborne outbreak of gastroenteritis caused by both Norovirus and Vibrio parahaemolyticus following the consumption of raw seafood in a restaurant in Terrassa (Catalonia, Spain) in September 2005. Measures are needed to reduce contamination of raw seafood. Consumers can reduce the risk of foodborne illness by avoiding consumption of raw or undercooked food.

Community outbreak of Legionnaires disease in Vic-Gurb, Spain in October and November 2005.

This paper reports the investigation of a community-acquired outbreak of Legionnaires' disease in the municipalities of Vic and Gurb (Central Region of Catalonia, Spain). There were 55 cases reported in October and November 2005. An epidemiological and environmental investigation was undertaken. Thirty-five case patients (64%) lived in Vic or Gurb, while 36% had visited or worked in Vic or Gurb during the 10 days before onset of symptoms, but no commonly frequented building could be identified. Water probes for culture were obtained from 30 cooling towers. In five cooling towers of two industrial settings in Gurb (plants A and B), Legionella pneumophila (Lp) serogroup 1 was present. Two Lp-1 strains were recovered from cooling towers in plants A and B. The Lp-1 strain from plant A showed a PGFE profile identical with those obtained from three patients. The exposure to Legionella pneumophila apparently occurred in a large area, since 43 of the 55 cases lived, visited or worked within a distance of 1,800 m from plant A, and six cases in a distance between 2,500 and 3,400 m. The inspections of cooling towers in plant A revealed inadequate disinfectant doses of biocide, non-existent maintenance records on weekends and wrong sample points for routine microbial check-ups. Weather conditions in October 2005 template temperature and high humidity (wind conditions are unappreciable) could have been favourable factors in this outbreak together with the flat terrain of Gurb and Vic area, explaining the extensive horizontal airborne dissemination of contaminated aerosols. The outbreak could have been prevented by proper and correct maintenance of the cooling tower at plant A.

Peripheral tissue release of interleukin-6 in patients with chronic kidney diseases: effects of end-stage renal disease and microinflammatory state.

To examine if uremia influences muscle interleukin-6 (IL-6) metabolism we studied the exchange of IL-6 across the forearm in 16 patients with chronic kidney disease (CKD) (stages 3 and 4), in 15 hemodialysis (HD)-treated end-stage renal disease (ESRD) patients (n=15), and in six healthy controls. In addition, we performed an analysis of both IL-6 protein and IL-6 mRNA expression in muscle of CKD (stage 4) patients showing evidence of inflammation and in controls. A release of IL-6 from the forearm was observed in patients with elevated IL-6 plasma levels. Arterial IL-6 was directly related to released IL-6 (r=0.69; P<0.004) in HD patients. Both IL-6 protein and IL-6 mRNA expression were increased in muscle of inflamed CKD patients vs controls (P<0.05). Although muscle net protein balance was similar in all patients, it was significantly more negative in HD patients with high than in those with low IL-6 plasma levels (P<0.05). In addition, net protein balance was related to the forearm release of IL-6 in HD patients only (r=0.47; P<0.038). These data demonstrate that IL-6 expression is upregulated in muscle, and that muscle tissue, by releasing this cytokine, may contribute to the inflammatory response in HD patients. The release of IL-6 from peripheral tissues is associated with an increase in muscle protein loss in HD patients, suggesting that muscle release of IL-6 is linked to protein catabolism in these patients. The release of IL-6 from peripheral tissues may act as a signal for the inflammatory response and contribute to functional dysregulation in uremia.

Waterborne epidemic outbreak of Shigella sonnei gastroenteritis in Santa Maria de Palautordera, Catalonia, Spain.

In August 2002 an outbreak of Shigella sonnei infection occurred in a Spanish town of 6343 inhabitants. In total, 756 people developed acute gastroenteritis and 181 cases were shigella-confirmed. The peak incidence was during 5-6 August 2002. The estimated primary attack rate was 9.97%; the attack rate for secondary cases was 38%. The <15 years ago group was most affected (16.49%). The town and its surroundings were served by two water systems, A and B. The cases had consumed water provided by system A (attack rate 164 cases/1000 population). Microbiological analysis of water from system A did not show the presence of coliform bacteria or shigella. This shigellosis outbreak was the largest reported in Spain. The impact of the epidemic was probably greater than the incidence detected.

An outbreak of food poisoning due to a genogroup I norovirus.

Norovirus infection is associated with approximately 90% of epidemic non-bacterial acute gastroenteritis. The objective of this study is to describe an outbreak of norovirus genogroup I gastroenteritis which affected workers in a hospital and was attributed to food prepared by an infected food handler. Forty cases were detected, of whom 80% were interviewed. The index case was the cook employed in the hospital cafeteria. The following symptoms were observed: abdominal pain in 90.6%, vomiting in 71.9%, diarrhoea in 71.9%, general indisposition in 62.5%, headaches in 53.1% and fever in 32.4% of cases. The initial symptoms were abdominal pain in 37% and vomiting in 28%. Of the 14 samples analysed by RT-PCR, 12 (86%) were positive for a genogroup I norovirus. After sequencing the strain was identified as genotype Desert Shield. Many of the foodstuffs consumed were made by hand, favouring transmission from the index case to the cafeteria users.