Antonino Bella

Estimates of Pandemic Influenza Vaccine Effectiveness in Europe, 2009–2010: Results of Influenza Monitoring Vaccine Effectiveness in Europe (I-MOVE) Multicentre Case-Control Study

Results from a European multicentre case-control study reported by Marta Valenciano and colleagues suggest good protection by the pandemic monovalent H1N1 vaccine against pH1N1 and no effect of the 2009–2010 seasonal influenza vaccine on H1N1.

Cross-reactive antibody responses to the 2009 A/H1N1v influenza virus in the Italian population in the pre-pandemic period

To assess in Italy the pre-pandemic susceptibility of the general population to the 2009 A/H1N1v influenza virus, 587 serum samples collected in 2004 were analyzed using haemagglutination-inhibition (HI), single-radial-haemolysis (SRH) and microneutralisation (MN) assays. Serum samples were stratified by age group, gender, and geographic area. Overall, using HI assay, the proportion of subjects showing antibodies cross-reacting with 2009 A/H1N1v virus at seroprotection level (>or=1:40) was estimated to be 6.7%, 12.4%, and 22.4% in individuals born between 2004 and 1949, 1948 and 1939, 1938 and 1909, respectively. With a HI antibody titre of >or=1:10, in the same birth cohort, the seroprotection levels were 13.5%, 19.2%, and 58.2%, respectively. The results suggest that the Italian population was not fully naïf to the current pandemic virus and that the possible previous exposure and immune response increases with age.

2-Week Triple Therapy for Helicobacter pylori Infection is Better Than 1-Week in Clinical Practice: a Large Prospective Single-Center Randomized Study

Background:  Proton pump inhibitor (PPI)‐based triple therapies are considered the standard regimens for Helicobacter pylori eradication, but the optimal duration of these regimens is still controversial. The aim of this study was to compare the efficacy of 1‐week versus 2‐week triple therapies in H. pylori‐positive patients.

The seroepidemiology of varicella in Italy.

We conducted a seroepidemiological study to evaluate the potential impact of mass varicella vaccination on the transmission of varicella-zoster virus (VZV) in Italy, where vaccination is not mandatory. We tested 3179 serum samples, collected from September 1996 to October 1997, for specific anti-VZV antibodies using a commercially available ELISA. The results confirmed that varicella typically involves children (82.1% seroprevalence among 10- to 14-year-olds) and that the mean age of acquiring the infection seems to be increasing. The results also revealed that southern Italy, compared to the rest of the country, has a greater circulation of VZV and an earlier age of acquisition. The potential impact of mass vaccination among 12- to 18-month-old children on the epidemiological trend of the infection must be carefully considered, in that failure to reach high levels of coverage could lead to an increase in the mean age of acquisition, which is already occurring in Italy.

Stepwise training in rectal and colonic endoscopic submucosal dissection with differentiated learning curves.

BACKGROUND Endoscopic submucosal dissection (ESD) has revolutionized the resection of GI superficial neoplasms, but adoption in Western countries is significantly delayed. OBJECTIVE To evaluate a stepwise colorectal endoscopic submucosal dissection (ESD) learning and operative training protocol. DESIGN Prospective study in the Western setting. SETTING This study took place in a nonacademic hospital with one endoscopist expert in therapeutic endoscopy but novice in ESD. PATIENTS Indications for ESD were superficial neoplasms 20 mm and larger without ulcerations or fibrosis. INTERVENTION Training consisted of 5 unsupervised ESDs on isolated stomach, an observation period at an ESD expert Japanese center, 1 supervised ESD on isolated stomach, and retraining on 1 rectal ESD under supervision. The operative training on patients was performed without supervision moving from the rectum to the colon according to the competence achieved. MAIN OUTCOME MEASUREMENTS Competence was defined as an 80% en bloc resection rate plus a statistically significant reduction in operating time per square centimeter. Learning curves were calculated based on consecutive blocks of 5 procedures. RESULTS From February 2009 to February 2012, 30 rectal and 30 colonic ESDs were performed. The rectal ESD learning curve showed that the en bloc resection rate was 80% after 5 procedures (P = not significant); the operating time per square centimeter significantly decreased after 20 procedures (P = .0079); perforation occurred in 1 patient. The colonic ESD learning curve showed that the en bloc resection rate was 80% after 20 procedures (P = not significant); the operating time per square centimeter significantly decreased after 20 procedures (P = .031); perforations occurred in 2 patients. LIMITATIONS Single-center design. CONCLUSIONS A minimal intensive training seems sufficient for endoscopists expert in therapeutic procedures to take up ESD in a not overly arduous incremental method with separate and sequential learning curves for the rectum and colon.

Distribution of serotypes and pulsotypes of Listeria monocytogenes from human, food and environmental isolates (Italy 2002-2005).

This work was undertaken to study the serotypes and pulsotypes of 674 Listeria monocytogenes isolates from human (57), food (558) and environmental (59) sources, collected from different Italian geographical areas during 2002-2005, to determine whether certain subtypes were associated with certain foods and more often involved in cases of listeriosis, and to determine possible geographical or temporal associations. Eleven different L. monocytogenes serotypes were found in the food, environmental and human isolates. Most isolates belonged to only four serotypes (1/2a, 1/2b, 1/2c, 4b). The isolates were divided into 133 distinct AscI pulsotypes grouped into 26 pulsogroups. Pulsogroups ranged from a minimum of 2 up to 212 isolates, and contained 1-19 different pulsotypes. When associations between subtypes and isolates from specific foods selected as being most frequently involved in cases of listeriosis were tested some of these associations were highly significant but not exclusive, indicating that there was no close correlation between specific subtypes and specific food products. Despite the limitations of this study (few human isolates versus many food isolates prevalently collected from one food category), we believe that a large-scale database of L. monocytogenes subtypes and a timely epidemiological investigation can facilitate risk assessment and outbreak detection and control.

Epidemiology of measles, mumps and rubella in Italy

A serosurvey for measles, mumps and rubella was conducted in Italy; incidence based on statutory notifications over the last three decades was also calculated. In Italy the diseases followed an endemic-epidemic pattern, with an incidence peak every 2-4 years, and had a limited reduction of incidence attributable to childhood immunization. Lower notification rates were observed in the Southern regions. This is possibly related to greater under notification in the South and is confirmed by our seroprevalence data. Incidence of measles and rubella and proportion of cases among young adults increased significantly in the three decades considered, but not for mumps. Serological data confirmed that these infections are still very frequent in Italy, without significant geographic variation in the country. In the age groups 2-4 and 5-9 years the percentage of individuals still susceptible to each virus was higher than 30%. The proportion of susceptible subjects older than 15 years was similar for the three infections (6.1, 11.7 and 8.8% for measles, mumps and rubella, respectively). The low vaccine coverage for rubella and measles in Italy has so far only partially affected the occurrence of the diseases. No impact of mumps vaccination is visible. The average number of deaths, for each disease, has decreased during the three study periods. Today the priority in Italy is to halt the progressive increase of the mean age of acquisition of the three infections, to eliminate differences in coverage among regions and to conform to European standards. This will be achieved through a combination of increasing MMR vaccine coverage before 2 years of age, implementing vaccination campaigns for low seroprevalence age groups, and/or introducing a second dose of MMR, depending on the level of current MMR coverage.

Protective effect of the AT137RQ and ARQK176 PrP allele against classical scrapie in Sarda breed sheep.

The susceptibility of sheep to scrapie is under the control of the host’s prion protein (PrP) gene and is also influenced by the strain of the agent. PrP polymorphisms at codons 136 (A/V), 154 (R/H) and 171 (Q/R/H) are the main determinants of susceptibility/resistance of sheep to classical scrapie. They are combined in four main variants of the wild-type ARQ allele: VRQ, AHQ, ARH and ARR. Breeding programmes have been undertaken on this basis in the European Union and the USA to increase the frequency of the resistant ARR allele in sheep populations. Herein, we report the results of a multi-flock study showing the protective effect of polymorphisms other than those at codons 136, 154 and 171 in Sarda breed sheep. All ARQ/ARQ affected sheep (n = 154) and 378 negative ARQ/ARQ controls from four scrapie outbreaks were submitted to sequencing of the PrP gene. The distribution of variations other than those at the standard three codons, between scrapie cases and negative controls, was statistically different in all flocks. In particular, the AT137RQ and ARQK176 alleles showed a clear protective effect. This is the first study demonstrating a protective influence of alleles other than ARR under field conditions. If further investigations in other sheep breeds and with other scrapie sources confirm these findings, the availability of various protective alleles in breeding programmes of sheep for scrapie resistance could be useful in breeds with a low frequency of the ARR allele and would allow maintaining a wider variability of the PrP gene.

Molecular characterization of intestinal protozoa in two poor communities in the State of São Paulo, Brazil.

BackgroundSeveral species of protozoa cause acute or chronic gastroenteritis in humans, worldwide. The burden of disease is particularly high among children living in developing areas of the world, where transmission is favored by lower hygienic standards and scarce availability of safe water. However, asymptomatic infection and polyparasitism are also commonly observed in poor settings. Here, we investigated the prevalence of intestinal protozoa in two small fishing villages, Porto Said (PS) and Santa Maria da Serra (SM), situated along the river Tietê in the State of São Paolo, Brazil. The villages lack basic public infrastructure and services, such as roads, public water supply, electricity and public health services.MethodsMultiple fecal samples were collected from 88 individuals in PS and from 38 individuals in SM, who were asymptomatic at the time of sampling and had no recent history of diarrheal disease. To gain insights into potential transmission routes, 49 dog fecal samples (38 from PS and 11 from SM) and 28 river water samples were also collected. All samples were tested by microscopy and PCR was used to genotype Giardia duodenalis, Blastocystis sp., Dientamoeba fragilis and Cryptosporidium spp.ResultsBy molecular methods, the most common human parasite was Blastocystis sp. (prevalence, 45% in PS and 71% in SM), followed by D. fragilis (13.6% in PS, and 18.4% in SM) and G. duodenalis (18.2% in PS and 7.9% in SM); Cryptosporidium spp. were not detected. Sequence analysis revealed large genetic variation among Blastocystis samples, with subtypes (STs) 1 and 3 being predominant, and with the notable absence of ST4. Among G. duodenalis samples, assemblages A and B were detected in humans, whereas assemblages A, C and D were found in dogs. Finally, all D. fragilis samples from humans were genotype 1. A single dog was found infected with Cryptosporidium canis. River water samples were negative for the investigated parasites.ConclusionsThis study showed a high carriage of intestinal parasites in asymptomatic individuals from two poor Brazilian villages, and highlighted a large genetic variability of Blastocystis spp. and G. duodenalis.

Clinical, social and relational determinants of paediatric ambulatory drug prescriptions due to respiratory tract infections in Italy

ObjectivesCollecting information on patterns of drug prescriptions and on factors influencing prescribing decisions is fundamental for supporting the rational use of drugs. This study was aimed at investigating patterns of drug prescription in paediatric outpatients and at evaluating determinants of prescriptions for respiratory tract infections (RTIs).MethodsWe conducted a national cross-sectional survey involving primary care paediatricians and parents. Diagnoses and prescriptions made at each consultation were described. Poisson regression models were used to analyse determinants of drug and antibiotic prescriptions for visits due to RTIs.ResultsA total of 4,302 physician and parent questionnaires were analysed. These corresponded to 2,151 visits, 792 of which were due to RTIs. Drugs were prescribed in 83.4% of RTI visits, while antibiotics were prescribed in 40.4%. According to paediatricians’ perceptions, 84.2% of parents of children with a RTI expected to receive a drug prescription. Paediatricians’ perception of parental expectations was the strongest determinant for prescription of drugs and specifically of antibiotics [adjusted relative risk (RR): 1.7 and 3.6, respectively; P < 0.001]. However, in 77.1% of RTI visits, paediatricians judged themselves as not being influenced at all by parents’ expectations in their decision to prescribe.ConclusionsThis study underscores that relational factors, in particular perceived parental expectations, are one of the leading factors of drug prescriptions in paediatric ambulatory care settings, reinforcing the opinion that communication between physicians and parents can affect prescription patterns.