The impact of COVID-19 pandemic on the incidence of acute gastroenteritis outbreaks in Catalonia (Spain)

We carried out a retrospective study of acute gastroenteritis (AGE) outbreaks reported between 1 January 2015 and 31 December 2021 in Catalonia (Spain) to compare the incidence from 2015 to 2019 with that observed from 2020 to 2021. We observed a higher incidence rate of outbreaks during the prepandemic period (16.89 outbreaks/1,000,000 person-years) than during the pandemic period (6.96 outbreaks/1,000,000 person-years) (rate ratio (RR) 0.41; 95% confidence interval (CI) 0.34 to 0.51). According to the aetiology of the outbreak, those of viral aetiology decreased from 7.82 to 3.38 outbreaks/1,000,000 person-years (RR 2.31; 95% CI 1.72 to 3.12), and those of bacterial aetiology decreased from 5.01 to 2.78 outbreaks/1,000,000 person-years (RR 1.80; 95% CI 1.29 to 2.52). There was a great reduction in AGE outbreaks in Catalonia. This reduction may have been due to the effect of the nonpharmaceutical measures applied to reduce the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but the collapse of the healthcare system and epidemiological surveillance services may also have had a strong influence.

Effectiveness and impact of the hepatitis B vaccination program in preadolescents in Catalonia 21 years after its introduction

Hepatitis B is a viral disease of global importance. In Catalonia in the 1980s, the seroepidemiological pattern of HBV infection was low-intermediate. In 1990, the Expert Committee on Vaccinations of the Department of Health of the Generalitat of Catalonia evaluated the systematic introduction of hepatitis B vaccination in preadolescents, maintaining the vaccination of risk groups. The objective of this study was to estimate the effectiveness and impact of the systematic hepatitis B vaccination programme in preadolescents in Catalonia 21 years after its introduction. A retrospective cohort study was conducted, comparing the disease incidence in vaccinated and unvaccinated cohorts. Cases of hepatitis B were defined as those reported by the General Subdirectorate of Surveillance and Response to Public Health Emergencies between 2000 and 2014. The incidence rate was 2.5 per 100,000 persons in 1991 and 1.2 per 100,000 persons in 2014, a reduction of 52%. During the study period, 388 cases of hepatitis B infection were notified, of which three were classified as vaccine failures. Vaccine effectiveness was 99.30% (95% CI: 97.83-99.78) and the population prevented fraction in the cohorts of preadolescents studied was 64.56% (95% CI: 60.45-68.66). The effectiveness and impact of the hepatitis B vaccination program in preadolescents in Catalonia is high, with the consequent benefits for the population.

Descriptive study of severe hospitalized cases of laboratory-confirmed influenza during five epidemic seasons (2010-2015)

OBJECTIVE

The Plan of Information on Acute Respiratory Infections in Catalonia (PIDIRAC) included the surveillance of severe hospitalized cases of laboratory-confirmed influenza (SHCLCI) in 2009. The objective of this study was to determine the clinical, epidemiological and virological features of SHCLCI recorded in 12 sentinel hospitals during five influenza seasons.

RESULTS

From a sample of SHCLCI recorded during the 5 influenza epidemics seasons from 2010-2011 to 2014-2015, Cases were confirmed by PCR and/or viral isolation in cell cultures from respiratory samples. A total of 1400 SHCLCI were recorded, 33% required ICU admission and 12% died. The median age of cases was 61 years (range 0-101 years); 70.5% were unvaccinated; 80.4% received antiviral treatment (in 79.6 and 24% of cases within 48 h after hospital admission and the onset of symptoms, respectively); influenza virus A [37.9% A (H1N1)pdm09, 29.3% A (H3N2)] was identified in 87.7% of cases. Surveillance of SHCLCI provides an estimate of the severity of seasonal influenza epidemics and the identification and characterization of at-risk groups in order to facilitate preventive measures such as vaccination and early antiviral treatment.

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.

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.

Changes in the epidemiology of hepatitis A outbreaks 13 years after the introduction of a mass vaccination program

A hepatitis A+B vaccine vaccination program of 12-year-olds was introduced in Catalonia in 1998. The aim of this study was to investigate the evolution of hepatitis A outbreaks in Catalonia and estimate the preventable fraction of cases associated with outbreaks as a measure of the impact of the vaccination program. Hepatitis A outbreaks reported to the Health Department between 1991 and 2012 were analyzed. The incidence rates of outbreaks, outbreak-associated cases and hospitalizations were calculated. The preventable fraction (PF) and 95% confidence intervals (CI) were estimated for the whole study period (pre-vaccination and post-vaccination) and the post-vaccination period.   One-hundred-eight (108) outbreaks (rate of 2.21 per 10(6) persons-year) were reported in the pre-vaccination period and 258 outbreaks (rate of 2.82 per 10(6) persons-year) in the post-vaccination period. The rate of cases associated with outbreaks was 1.52 per 10(5) persons-year in the pre-vaccination period and 1.28 per 10(5) persons-year in the post-vaccination period. Hospitalization rates were 0.08 and 0.75 per 10(6) persons-year, respectively. The number of person-to-person outbreaks whose index case was a school contact decreased in the post-vaccination period (aOR 2.72; 95%CI 1.35-5.48), but outbreaks whose index case was a man who has sex with men (MSM) or an immigrant increased. The PF of all outbreak-associated cases was 6.46% (95%CI 3.11-9.82) and the highest PF was in the 15-24 years age group (42.53%; 95%CI 29.30-55.75). In the 0-4 years age group, the PF was 18.35% (95%CI 9.59-27.11), suggesting a protective herd effect in unvaccinated subjects. Vaccination of immigrants traveling to endemic countries and MSM should be reinforced.

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.

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.

Epidemiology of pertussis in a country with high vaccination coverage

INTRODUCTION

Pertussis has been a preventable disease in Catalonia since 1965, but the annual number of cases remains high. The aim of this study was to analyze the epidemiology of pertussis in Catalonia and its implications for control purposes.

METHODS

An epidemiological study was carried out in Catalonia between 2004 and 2008. Pertussis cases reported to the Department of Health were collected and disease reports were filled out with the case information. Incidence rates, rate ratios (RR) and their 95% confidence intervals (CI) were calculated.

RESULTS

963 cases were reported: 555 (57.6%) were confirmed and 408 (42.4%) were suspected cases. The reported incidence rate was 2.01 × 10(-5) person years in 2004 and 4.34 in 2008. The biggest increase in cases between 2004 and 2008 was observed in the ≥35 years age group (RR: 6.98; 95%CI: 2.11-36.36). 303 (31.5%) patients were hospitalized, of whom 93.7% were aged <1 year. Clinical differences were observed in paroxysmal cough (83.8% in suspected and 76.4% in confirmed cases, p=0.005), posttussive vomiting (47.1% and 36.1%, respectively, p=0.001), apnoea (13.7% and 21.3%, respectively, p=0.003) and fever (20.1% and 12.4%, respectively, p=0.001).

CONCLUSION

Pertussis incidence rates increased during the study period, with the greatest increase occurring in the ≥35 years age group. A booster dose of vaccine in young people could reduce the circulation of B. pertussis in adolescents and adults and indirectly reduce the incidence in children.

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.

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.

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.

Mumps: a year of enhanced surveillance in Catalonia, Spain

Mumps is a vaccine-preventable disease candidate for elimination. Positive predictive value (PPV) of clinical case definition was assessed. During 2007, 410 suspected cases were reported in Catalonia: 348 fulfilled clinical case definition and 159 were laboratory confirmed. Incidence rate was 4.8 per 100,000 for cases that fulfilled the clinical definition, and 2.2 for laboratory confirmed cases. Global PPV was 44.5%; 38.5% in <15 years and 50% in > or =15 years (p=0.04). Most laboratory confirmed cases (72.3%) received at least one MMR dose. With sustained high MMR coverage, laboratory confirmation is necessary to control the disease and assess vaccine failure.

Large outbreak of measles in a community with high vaccination coverage: implications for the vaccination schedule

BACKGROUND

Attempts to eliminate measles from a country or region may be disrupted by an imported case that affects indigenous persons. The objective of this study was to analyze epidemiological and clinical characteristics of a measles outbreak in Catalonia, Spain, in 2006.

METHODS

Data on cases of measles reported to the Department of Health, Generalitat of Catalonia, during the period 28 August 2006 through 8 July 2007 were collected. Suspected cases were confirmed by determination of measles-specific immunoglobulin M antibodies and/or detection of virus genome. Incidences were calculated using the estimated population of Catalonia for 2006, and 95% confidence intervals were determined assuming a Poisson distribution. The association between proportions was determined using the chi(2) test and Fisher's exact test. The level of statistical significance was set at alpha = .05.

RESULTS

A total of 381 cases were confirmed, for an incidence of 6.6 cases per 100,000 persons. A total of 89.5% of cases occurred in nonvaccinated persons, mainly those aged < or =15 months (incidence, 278.2 cases per 100,000 persons; mean age of patients, 12 months). Indigenous subjects accounted for 89.8% of cases, and laboratory confirmation of results was obtained for 87.1%. Measles genotype D4 was identified in all sequenced samples.

CONCLUSIONS

The age distribution of cases of measles among children aged <15 months suggests that the first dose of vaccine should be routinely administered at the age of 12 months.

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.

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.

Measles outbreak in the Barcelona Region of Catalonia, Spain, October 2006 to February 2007

From 1 October 2006 to 31 January 2007, 213 confirmed cases of measles occurred in the Barcelona Region, resulting from the importation of one case.

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.

[Reporting of newly diagnosed HIV infections in Catalonia, Barcelona, Spain. Implementation and results]

OBJECTIVES

To describe newly diagnosed HIV infections from the HIV Reporting System in Catalonia (2001-2003), and to compare the characteristics of the epidemic based on the use of the HIV Reporting System and the Catalonian AIDS Registry versus those based on the Catalonian AIDS Registry alone.

METHODS

Data were collected from newly diagnosed HIV infections and AIDS cases between 2001 and 2003 in Catalonia.

RESULTS

Among the newly diagnosed HIV infections (1,765) the most frequent route of HIV infection was heterosexual transmission (46.8%), followed by men who had sex with men (26.7%), and injecting drug use (19.9%). Out of the 1,210 AIDS cases, the most common route of HIV transmission was injecting drug used (42.2%), followed by (heterosexual transmission 34.5%) and MSM (18.0%). Comparison of routes of HIV transmission in the two reporting systems (HIV/AIDS versus AIDS) revealed statistically significant differences.

CONCLUSIONS

The HIV/AIDS Reporting System based on reporting of newly diagnosed HIV infections is feasible, since it has been useful in achieving the objectives of epidemiological HIV infection surveillance. It also provides more accurate information than does the AIDS Registry, which can be used to describe recent patterns of HIV transmission. The completeness of the new reporting system may be enhanced by including the diagnosis of HIV infection among the diseases of mandatory notification.

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.

[Colonization by group B hemolytic streptococcus in pregnancy. Note of prevention and therapy of the materno-neonatal infection. Casuistics]

As several international studies show, the knowledge of the wide clinical spectrum of perinatal group B streptococcal infection, particularly of the early and of the late-onset neonatal diseases in GBS carrier mothers, is basically important for medical diagnosis. Risk factors analysis further determines both the diagnosis and the maternal intrapartum chemoprophylaxis. The considerable rate of neonatal disease without risk factors and its possible serious and fatal consequences bring to tendentially non selective prevention approaches that must consider the local background. At Merate Hospital, in a 3 years time, vaginal and rectal specimens for GBS cultures were obtained from 1766 pregnant women either at the 32nd or at the 36th week of gestation and regularly at the labor. 376 women (21.29 percent) resulted GBS carriers; the maternal-fetal contamination rate was 15.42 percent (58/376) i.e. 32.6 per 1000 live births (58/1769). Intrapartum chemoprophylaxis was carried out with i.v. erytromycin, i.v. or i.m. cephalosporins, i.v. ampicillin and per os amoxicillin (which gave the most interesting results). In infants born to mothers who received an antibiotic therapy at labor as compared with those who received no treatment, GBS neonatal colonization was present in 31 of 286 (10.8 percent) versus 27 of 90 (30 percent; P < 0.001); heavy colonization was observed in 10 of 286 (3.4 percent) versus 15 of 90 (16.6 percent; P < 0.001) and early-onset neonatal disease (both symptomatic and asymptomatic) occurred in none of 286 versus 4 of 90 (4.44 percent; P = 0.0031). Perinatal risk factors (no-screened mothers, labor at 36th week of gestation, prolonged membrane rupture) were present only in 1 of 4 GBS infected infants (25 percent). Intrapartum therapy both in carriers and in no-screened women significantly reduced GBS neonatal colonization, particularly the heavy one and, consequently, the early-onset neonatal group B streptococcal disease.

Skeletal muscle protein synthesis and degradation in patients with chronic renal failure

Muscle protein turnover and amino acid (AA) exchange across the forearm were studied in nine postabsorptive patients with chronic renal failure (CRF) under unrestricted calorie-protein diets and eight controls by using the arterio-venous difference technique associated with the 3H-phenylalanine kinetics. In patients with CRF: (1) the rate of appearance (Ra) of phenylalanine (Phe) from the forearm, reflecting proteolysis, was 27% increased in comparison with controls (P < 0.01). Also the rate of disposal (Rd) of Phe, reflecting protein synthesis, was increased in patients (P < 0.01). As a consequence of these counterbalanced alterations, net balance of Phe across the forearm, that is, net proteolysis, was not changed. (2) The release of total AA from the forearm was not different from controls. Valine and ketoisocaproate release was reduced (P < 0.05). Serine uptake was not detectable. (3) Net proteolysis and the Rd/Ra ratio were inversely and directly, respectively, related to arterial [HCO3-] (P < 0.02 and P < 0.03, respectively). (4) Moreover, net proteolysis and Phe Rd/Ra ratio were directly and inversely, respectively, correlated with plasma cortisol (P < 0.01 and < 0.005, respectively). Plasma cortisol was in the normal range and inversely related to arterial [HCO3-] (P < 0.02). (5) While in controls phenylalanine appearance from the forearm was inversely related to insulin levels, no correlation was found in patients. In conclusion, in patient with CRF, forearm Phe kinetics indicate the existence of an increased muscle protein turnover. Changes in protein synthesis and degradation are well balanced and net proteolysis is not augmented.(ABSTRACT TRUNCATED AT 250 WORDS)

[Celiac disease and the evolution of its diagnosis. Comparison and experience at a hospital pediatric department (1975-1993). (Second part)]

In a period of over 18 years the prominent medical bibliographic marks with regard to definition, diagnosis and examinations of coeliac disease (CD) have been compared and as far as possible reproduced. The results confirm the remarks derivating from wider statistics. From the beginning of 1975 to the first six months of 1993 in Merate Hospital Pediatric Division, 323 patients were submitted to a first jejunal peroral biopsy in 133 cases (41.2%) CD was diagnosed. Since 34 children (25.6%) concluded the ESPGAN diagnostic iter with 3 consecutive biopsies, the reasons why the other patients didn't finish or respect the programs are here examined. Since 1987 a specific anti-gliadin (IgA and IgG) antibodies titrimetry has been available either in the investigation of suspect symptomatology or like control mark during the assessment or after a sure CD diagnosis. Since october 1992 antiendomysium antibodies (EMA or AEA IgA) have been determined only in selected patients. From the examination of 24 subjects now checked with AGA IgA/IgG and EMA and with a first positive biopsy, it is possible to point out that only one jejunal biopsy (or at the most a second one as a control during the gluten challenge) with the guarantee of haematologic patterns doesn't raise doubts about a CD diagnosis. Analogous considerations mainly refer to the atypical CD "late onset" when a constant lack of AGA and EMA during gluten free diet (GFD) or their changes in a non compliance or in gluten challenge, can exclude a following hystological confirmation. By this experience it follows that a specific antigliadin and antiendomysium antibodies investigation is indispensable to the shortening of diagnostic times, to the reduction of an often unwelcome invasive diagnostic method and to the discovery of the "CD iceberg".

Erythropoietin treatment and amino acid metabolism in hemodialysis patients

A previous report suggests that treatment with recombinant human erythropoietin (rH-EPO) significantly improves many abnormalities in circulating amino acids (AA) in hemodialysis patients. We evaluated the effects of a 12-month treatment with rH-EPO (150-250 U/kg/week) on blood AA levels in 10 patients with chronic renal failure under regular dialytic treatment. During treatment, hemoglobin levels increased from 7.0 +/- 0.3 to 10.1 +/- 0.3 g/dl at 3 months remaining steady thereafter. Before the treatment, patients showed reduced levels of essential AA (EAA), mainly valine, leucine and threonine (p < 0.05-0.01); among non-EAA (NEAA), aspartate and serine were reduced, whereas glycine, alanine, proline, citrulline and cyst(e)ine were increased (p < 0.05-0.001). Val/Gly, Ser/Gly and Tyr/Phe ratios were low (p < 0.05-0.01). Total EAA and total NEAA (619 +/- 21 and 1,382 +/- 75 mumol/l, respectively, before the study) were unchanged (639 +/- 22 and 1,410 +/- 89 mumol/l, respectively) at 12 months. Abnormalities in AA levels observed before the treatment persisted throughout the study. Only serine increased at the end of the study (p < 0.05). In conclusion, contrary to what has been reported, treatment with rH-EPO is not associated with an amelioration of AA metabolism in hemodialysis patients.

[Celiac disease and its diagnostic evolution. Comparisons and experiences in a hospital pediatric department (1975-1992). I]

The coeliac disease (CD) or gluten-sensitive enteropathy (GSE) is a permanent intolerance to wheat gliadin and to correlated proteins inducing malabsorption and typical damages of the jejunal mucosa (total or subtotal villous atrophy = SVA) in genetically-predisposed individuals ("DQW2"). A large amount of research has been devoted to CD pathogenesis: the most recent studies, thanks to sophisticated and experimental methods, support the pathogenetic immunological theory and the one of direct cytotoxicity. The correct diagnostic procedure for CD, established in 1970 by the European Society for Pediatric Gastroenterology and Nutrition (ESPGAN), suggested three small bowel mucosal biopsies. In the last years, because of the difficulties of such a practice, the necessity of non-invasive diagnostic approaches has developed; such approaches have been verified in absorption tests (one-hour blood xylose, intestinal permeability methods) and in immunogenetic tests (antibodies antigliadin, anti-reticulin, anti-endomysium, anti 90 KD glycoprotein, anti-human jejunum, HLA I/II antigens). The specific MHC antigens establish CD's incidence in several population and in particular situations, as in first-degree relatives and in diseases associated with CD (dermatitis herpetiformis (DH), insulin dependent diabetes mellitus (IDDM) and other auto-immune syndromes). The specific serum antibodies singly used as first level screening if estimated in combination with absorption tests, reach the highest levels of specificity and sensibility in CD diagnosis. It's anyway fundamental the comparison with at least a typical CD histological feature, caused by a challenge with a sufficient gluten to be carried in dubious cases and in non high auxological risk age (ESPGAN 1989). Adolescence is a period of frequent non compliance with a gluten-free diet and of particular psychological and physical problems: the apparent "gluten insensitivity", typical of teen-agers and adults, recalls the definitions of silent CD and latent CD (iceberg like). In the first case the jejunal mucosa is abnormal and the symptomatology isn't evident. In latent CD, genetically restricted, the mucosa is normal but there are minimal markers of inappropriate immunity to gliadin (at intestinal humoral immunity level) and a possible worsening of histological lesions to the third stage under environmental stimuli. This represents a two-stage model CD. That's why CD is still under-evaluated despite recent statistics reporting an increasing incidence (late and atypical forms). Prevalence rates between 1:300 and 1:4,000 and more are quoted in literature. The necessity of a strict gluten-free diet is confirmed by the evident frequency of lymphoma and by the increased risk of malignancy in untreated CD.(ABSTRACT TRUNCATED AT 400 WORDS)

Reversed-phase high-performance liquid chromatographic analysis of branched-chain keto acid hydrazone derivatives: optimization of techniques and application to branched-chain keto acid balance studies across the forearm

A sensitive method of quantifying branched-chain keto acids in plasma and whole blood samples is described. It is based on the separation by ion-pair reversed-phase liquid chromatography of 2,4-dinitrophenylhydrazine derivatives with ultraviolet detection. The sample clean-up steps that are usually required for reversed-phase high-performance liquid chromatography are eliminated. A reduction in ketoisocaproate isomer formation is obtained by incubation of derivatives in ice. The method is reproducible (coefficient of variation 2%, n = 5, at the 200-pmol level) and the ultraviolet response is linearly related to branched-chain keto acid concentration. Recoveries are high (greater than 95%). Other keto acids do not co-elute with branched-chain keto acids. Because of its sensitivity and precision, this method can be proposed for whole blood branched-chain keto acid balance studies across organs.

[A community outbreak of Legionnaires' disease in Barcelona: epidemiologic and environmental study]

The investigation of the outbreak of legionellosis which developed in Barcelona in February 1988 included: 1) a case-control study, with the patients with Legionella pneumophila pneumonia (n = 56) and those with pneumonia by other organisms (n = 109) in the Hospital Clínic i Provincial (HCP); 2) a review of refrigeration towers and the water supply system; 3) a meteorological study, and 4) a survey of the construction works being carried out in the HCP area. The cases lived in the urban district 2 more often than the controls (odds ratio = 3.73, 95% confidence intervals 1.8-7.6), and were not associated with hospitals of hotels. L. pneumophila was not recovered from the environmental samples. The temperatures were unusually high, with a low air humidity. In the area near the HCP demolition materials were frequently removed. A causative focus was not detected; it cannot be ruled out, however, that the source of the outbreak was the removal of demolition materials in the affected area on the days preceding the epidemic outbreak.

[Polycenter evaluation of the break-point system]

Several research center have been set up to evaluate the system that deals with sensitivity to microbes under Sensititre break-point. The study has been broken down as follows: the break-point system was compared with the agar diffusion according to Bauer et al., using 1180 strains of fast-growing Gram-negative bacteria; a limited number of strains (176) have been used to compare the Sensititre break-point and the Sensititre MIC; results have been obtained testing 448 strains processed by break-point with correct inoculum and with simplified inoculum, from a colony; an investigation has been carried out on the time and cost of the break-point functioning. Having taken the Bauer system and others are compared them with the break-point, it was seen that their total agreement was 90.3% with 2% of major disagreement. The total major disagreement between Sensititre MIC and Sensititre break-point was 2.7%. The total major disagreement of the latter was largely the result of cephalotin (21%) on the Escherichia coli strains. An initial research centre has been formed to try to trow light upon the origins of such disagreements and we are now pleased to report back their initial findings. The preparation and reading of a test with the Bauer system and others takes about 18 minutes and costs 5600 Lit; a break-point test takes 10 minutes and costs 4500 Lit.

[N.B.T. - PABA screening test for exocrine pancreatic function in healthy children. Preliminary investigation in 60 normal children]

The theoretical bases of PABA test as a diagnostic screening test of exocrine pancreatic insufficiency, its mode of execution and the findings obtained in 60 healthy subjects ranging in age from 2 to 14 years are reported. Those conditions related to extra-pancreatic disorders or to other factors that may interfere with the test and reduce its reliability are also discussed.