Characteristics Of Outbreak Research Articles

Worm propagation model in mobile network

SummaryWith the popularity of mobile smart devices and functional diversification, the infection ways of mobile smartphones worm also become diverse. In mobile networks, mobile devices are suffering from the threat of worms all the time. Once the worm outbreaks, it will bring huge losses to mobile phone users and mobile network operators. Researches on mobile worm propagation model allow us to control and detect potential worm threat, according to the characteristics of worm's outbreak. In the paper, we put forward a worm propagation model based on the mobile network environment. After analyzing the model, we then give the simulation for controlling factors affecting worm propagation. This model allows us to have a certain understanding for the spread on the size and speed of the mobile worm and provide effective methods to control the spread of the mobile worm. Copyright © 2015 John Wiley & Sons, Ltd.

Characteristics of a large mumps outbreak: Clinical severity, complications and association with vaccination status of mumps outbreak cases

In recent years, large mumps outbreaks, involving mainly adolescents and young adults, have re-emerged in several countries. We investigated a large mumps outbreak, evaluated the association between mumps clinical severity (complications, hospitalization) and vaccination status (number of previous measles, mumps and rubella - MMR vaccine doses), and assessed vaccine effectiveness. The first mumps cases emerged in an ultra-orthodox boys' school in Jerusalem and were epidemiologically linked to the mumps outbreak in New York. Overall, 3130 mumps cases were notified in the Jerusalem district during September 2009-August 2011 (median age 13y, 64% males). Most cases were reported from community clinics. Patients with systemic symptoms and/or complications (419, 13.4%) were either hospitalized (n = 79) or treated in an emergency medical center (n = 340). The main complications included orchitis (3.8% males> age 12y) and meningoencephalitis (0.5%). The mumps virus genotype was G5. The distribution of previous MMR vaccine doses (n = 0,1,2) was: 24.8%, 28.3% and 46.9%, respectively. The number of previous vaccine doses was inversely associated with clinical severity. Adjusted values for MMR vaccine effectiveness against complications were estimated as 52.1% (95% CI −4 −78%) for one vaccine dose and 62.7% (95% CI 25.7–81.3%) for 2 doses. The outbreak was characterized by predominance of male students; the majority of whom had been previously vaccinated. The reported complication rate was relatively low. Vaccination status was associated with age and disease severity. The combination of limited mumps vaccine effectiveness and the specific school setting (dense learning and living conditions) probably contributed to the disease spread.

Epidemiological, Clinical and Entomological Characteristics of Yellow Fever Outbreak in Darfur 2012.

The study aims at analyzing the epidemiological, clinical and entomological characteristics of Darfur yellow fever epidemic. It is a descriptive, cross-sectional study. According to operational case definition, suspected yellow fever cases are included in case spread sheet with variables like age, sex, locality, occupation, status of vaccination, onset of symptoms, presenting symptoms, date of blood sampling and confirmation of diagnosis either by laboratory results or epidemiological link. Data about important entomological indices were collected by surveys conducted in 17 localities of 3 Darfur states (Central, West and south Darfur). All Darfur states (especially Central Darfur) have been affected by Yellow Fever outbreak. There is a need to review the non-specific case definition of Yellow Fever which seems to overwhelm the system during outbreaks with cases of other endemic diseases. The significant risk factors of this outbreak included male sex, adult age, outdoor occupation and traditional mining. The fatality rate was significantly associated with vaccination status. The highest fatality rate was recorded by children less than 2 years old (42.9%). Generally, increase in certain entomological indices was followed by increase in number of reported cases 7 days later. Central Darfur state was significantly higher in most studied entomological indices.

Descriptive epidemiology of school outbreaks of seasonal influenza B during 2012/2013 in the Thames Valley, United Kingdom

• The extent and characteristics of influenza outbreaks in three primary schools have been described.

Achromobacter bacteraemia outbreak in a paediatric onco-haematology department related to strain with high surviving ability in contaminated disinfectant atomizers

Achromobacter spp. are Gram-negative bacilli from aqueous environments, occasionally involved in bacteraemia in immunocompromised hosts and in outbreaks. We describe the characteristics of an achromobacter bacteraemia outbreak in a paediatric onco-haematology department. Throughout a one-year period, 16 blood cultures from seven patients were positive for Achromobacter sp. All patients were immunocompromised, febrile, and central venous catheter (CVC) holders. A microbiological study was performed in patients' rooms, completed with an analysis of the disinfectant atomizers (didecyl diammonium chloride 0.25%, Surfanios, DMA). In total, 41 clinical and environmental strains were analysed by enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction (PCR), repetitive PCR, and random amplified polymorphic DNA (RAPD)-PCR, and pulsed-field gel electrophoresis (PFGE). The bactericidal activity of DMA was studied on two Achromobacter sp. representative strains and one Pseudomonas aeruginosa reference strain, comparing biofilm and planktonic growth models. The seven patients, including two severe cases, were successfully treated by systemic antimicrobial therapy and/or catheter removal. The 25 environmental isolates were recovered with the following chronology: hospital filtered tap water, disinfectant atomizers, and patients' rooms. All environmental, patient, and atomizer strains had identical PCR and PFGE patterns. The disinfectant susceptibility assay revealed that the strain isolated from the atomizers had high survival abilities in biofilm conditions and remained resistant to DMA after short contact periods. The use of disinfectant atomizers associated with the survival of Achromobacter in the atomizer pipes may explain the contamination and colonization of the CVC. Control measures (non-atomizer containers and use of sterile water) allowed the eradication of the source and the outbreak control.

Quantifying the determinants of outbreak detection performance through simulation and machine learning

ObjectiveTo develop a probabilistic model for discovering and quantifying determinants of outbreak detection and to use the model to predict detection performance for new outbreaks. Materials and methodsWe used an existing software platform to simulate waterborne disease outbreaks of varying duration and magnitude. The simulated data were overlaid on real data from visits to emergency department in Montreal for gastroenteritis. We analyzed the combined data using biosurveillance algorithms, varying their parameters over a wide range. We then applied structure and parameter learning algorithms to the resulting data set to build a Bayesian network model for predicting detection performance as a function of outbreak characteristics and surveillance system parameters. We evaluated the predictions of this model through 5-fold cross-validation. ResultsThe model predicted performance metrics of commonly used outbreak detection methods with an accuracy greater than 0.80. The model also quantified the influence of different outbreak characteristics and parameters of biosurveillance algorithms on detection performance in practically relevant surveillance scenarios. In addition to identifying characteristics expected a priori to have a strong influence on detection performance, such as the alerting threshold and the peak size of the outbreak, the model suggested an important role for other algorithm features, such as adjustment for weekly patterns. ConclusionWe developed a model that accurately predicts how characteristics of disease outbreaks and detection methods will influence on detection. This model can be used to compare the performance of detection methods under different surveillance scenarios, to gain insight into which characteristics of outbreaks and biosurveillance algorithms drive detection performance, and to guide the configuration of surveillance systems.

Characteristics of pertussis outbreaks in Catalonia, Spain, 1997 to 2010

In Catalonia, pertussis outbreaks must be reported to the Department of Health. This study analyzed pertussis outbreaks between 1997 and 2010 in general and according to the characteristics of the index cases. The outbreak rate, hospitalization rate and incidence of associated cases and their 95%CI were calculated. Index cases were classified in two groups according to age (<15 years and ≥15 years) and the vaccine type received: whole cell vaccine (DTwP) or acellular vaccine (DTaP). During the study period, 230 outbreaks were reported. The outbreak rate was 2.43 × 10−6 persons-year, and outbreaks ranged from 2 to 32 cases, with a median duration of 18 days. There were 771 associated cases, with an incidence rate of 0.8 × 10−5 persons-year. After classifying outbreaks according to the age of the index case, 126 outbreaks (1.3 × 10−6 persons-year) had an index case aged <15 y and 87 (0.87 × 10−6 person-year) had an index case aged ≥15 y (RR = 1.44, 95%CI 1.10–1.90; P = 0.007). Between 2003 and 2010, after the introduction of the acellular vaccine, the index case was vaccinated with DTwP vaccine in 25 outbreaks (0.43 × 10−6 persons-year) and with DTaP vaccine in 32 outbreaks (0.55 × 10−6 person-year) (RR = 0.78, 95%CI 0.46–1.31; P = 0.35). Of cases, 37.2% were correctly vaccinated, suggesting waning immunity of pertussis vaccine protection and endogenous circulation of pertussis. A greater number of outbreaks had an index case aged <15 y. No changes in the disease incidence, associated cases and hospitalization rate were observed after the introduction of DTaP.

Establishing criteria to initiate enteric outbreak investigations in British Columbia.

To establish and evaluate criteria to initiate provincial enteric outbreak investigations based on characteristics of alerts, clusters and successful outbreak investigations. We tracked all enteric disease alerts and clusters reported to the British Columbia Centre for Disease Control (BCCDC) in 2011 and 2012. Information was collected on etiology, number of cases, geographic spread, dates reported, and method of notification. Actions were classified as no further action, review/report or investigation. Outbreak investigation outcome was classified as solved/not solved. 2011 data were used to identify characteristics of alerts and clusters more likely to lead to outbreak investigations and of solved outbreaks to establish criteria. Criteria for initiating an outbreak investigation were evaluated retrospectively using 2011 data and then implemented in 2012. In 2011, 251 alerts/clusters of enteric diseases were reported. Fourteen (5.6%) led to an outbreak investigation and nine (64.3%) of the outbreaks were solved. Analyzing the data retrospectively, criteria were identified from the alerts and clusters that led to outbreak investigations and successful outbreak investigations: pathogen specificity, timely notification, a common source or event, and multi-regional outbreaks or outbreaks reported by other agencies. After applying these criteria prospectively in 2012, we took action on a smaller proportion of the 244 alerts and clusters (32.0% compared to 44.6% in 2011) and 66.7% of them were solved (compared to 64.3% in 2011). Continued evaluation will identify whether this will improve outbreak investigations and use of resources in British Columbia.

Ranking of Tornado Outbreaks across the United States and Their Climatological Characteristics

Abstract The calendar year 2011 was an extraordinary year for tornadoes across the United States, as it marked the second highest annual number of tornadoes since 1950 and was the deadliest tornado year since 1936. Most of the fatalities in 2011 occurred in a series of outbreaks, highlighted by a particularly strong outbreak across the southeastern United States in late April and a series of outbreaks over the Great Plains and Midwest regions in late May, which included a tornado rated as a category 5 event on the enhanced Fujita scale (EF5) that devastated the town of Joplin, Missouri. While most tornado-related fatalities often occur in outbreaks, very few studies have examined the climatological characteristics of outbreaks, particularly those of varying strength. In this study a straightforward metric to assess the strength, or physical magnitude, of tornado outbreaks east of the Rocky Mountains from 1973 to 2010 is developed. This measure of outbreak strength, which integrates the intensity of tornadoes [Fujita (F)/EF-scale rating] over their distance traveled (pathlength), is more highly correlated with injuries and fatalities than other commonly used variables, such as the number of significant tornadoes, and is therefore more reflective of the potential threat of outbreaks to human life. All outbreaks are then ranked according to this metric and their climatological characteristics are examined, with comparisons made to all other tornadoes not associated with outbreaks. The results of the ranking scheme are also compared to those of previous studies, while the strongest outbreaks from 2011 are ranked among other outbreaks in the modern record, including the April 1974 Super Outbreak.

The Balkan region: NDM-1-producing Klebsiella pneumoniae ST11 clonal strain causing outbreaks in Greece.

Despite the fact that the NDM-1 carbapenemase has successfully disseminated worldwide, outbreaks remain uncommon in the European region. We describe the characteristics of the first outbreaks caused by NDM-1-producing Klebsiella pneumoniae clonal isolates in Greece. Between January 2010 and June 2013, 132 non-repetitive carbapenem-resistant Enterobacteriaceae isolates, which gave a positive modified Hodge test and were phenotypically suspected of metallo-β-lactamase production, were recovered from patients hospitalized at Ioannina University Hospital. Resistance genes were identified by PCR and sequencing. Plasmid profiling, conjugation experiments, enterobacterial repetitive intergenic consensus PCR, PFGE and multilocus sequence typing (MLST) were performed. Patient records were retrieved to access patterns of acquisition. Molecular testing verified the presence in 78 K. pneumoniae isolates, collected from 71 patients, of the blaNDM-1 gene. The blaCTX-M-15, blaOXA-1 and blaTEM-1 genes were also present in most isolates. The blaNDM-1 gene was located on a narrow host range IncFII-type plasmid, of ∼95 kb, flanked upstream by a non-truncated ISAba125 element and downstream by the bleMBL gene. Genotyping clustered all K. pneumoniae isolates into a single clonal type with one subtype and MLST assigned them to sequence type 11. Two outbreaks were noted, the first between November and December 2011 involving four patients and the second initiated in May 2012 and ongoing, involving the remaining patients. All but two cases were characterized as hospital acquired. No links to immigration or travel history to endemic areas were established. This survey highlights the successful undetected dissemination of yet another carbapenemase in Greece and strengthens the hypothesis of a latent NDM-1 cluster in the Balkan region.

Emergence of vanA vancomycin-resistant Enterococcus faecium in a hospital in Porto Alegre, South Brazil

In Porto Alegre (South Brazil), since the first VRE isolation in 2000 until the middle of the last decade, the epidemiology of enterococcal infections presented the peculiarity that, as opposed to other regions of the country, almost all VRE were E. faecalis. The aim of this study was to investigate the microbiological and epidemiological characteristics of a VRE outbreak that occurred between August 2010 and September 2011 in Porto Alegre, South Brazil. Twenty-nine isolates from inpatients of Mãe de Deus Hospital that were identified and characterized for their susceptibility profile, vancomycin genotype, presence of esp gene, biofilm production, and clonal relationship were collected. Patients' records were reviewed for clinical information. All isolates were identified as vancomycin/ampicillin resistant E. faecium carrying the vanA gene. Almost all were susceptible to gentamicin and streptomycin. Most patients died and were associated with a hemodialysis unit stay. All but the first isolate were clustered in a main clone. An important change in vancomycin-resistant enterococci was observed. Studies like this are necessary to monitor the dissemination of VRE, especially of some individual clones.

INDIVIDUAL-BASED COMPUTATIONAL MODEL USED TO EXPLAIN 2009 PANDEMIC H1N1 IN RURAL CAMPUS COMMUNITY

In the beginning of fall semester 2009, over 2,000 students contacted the student health service at Washington State University to report symptoms of influenza. The epidemic in Pullman, WA made national news, and many speculated on the severity and extent of the disease spread. Analysis of data from the influenza A(H1N1)pdm09 epidemic in Pullman, WA offers an opportunity to gain insights into characteristics of this rural campus community outbreak. In this study, an individual-based stochastic epidemic simulation model was used with the data to estimate infection parameters and make projections of the number of symptomatic individuals that would result given a variety of plausible scenarios. The parameters that were estimated include the number of individuals initially infected and the basic reproductive ratio (R0). The model was then used to predict the magnitude of infection with vaccination, isolation and quarantine. The results show that the best single intervention strategy is vaccination, and the reduction in infection is greatest when vaccination, isolation and quarantine are used simultaneously.

Molecular epidemiology study on an acute gastroenteritis outbreak caused by a new GII. 4 norovirus recombinant strain

To analyze the epidemiological characteristics of an acute gastroenteritis outbreak in a nursing home caused by norovirus (NoV) and the genotype of the pathogen. On January 29th 2013, a total of 26 acute gastroenteritis patients infected by norovirus were reported in the nursing home of Jinshan, Shanghai. A questionnaire was used to acquire information of patients involved in the outbreak, 9 stool or anal swab samples were collected from 9 patients without treatment by simple random sampling method, and 4 environmental samples from the surface of doorknobs or toilets were collected. The samples were detected by Real-time PCR for NoV, and positive samples were then amplified by routine RT-PCR. The PCR products were purified, sequenced, and aligned by comparing sequences in GenBank. Phylogenetic trees were constructed by using Clustal X, employing MEGA 5.1 program package. For the 26 patients, 7 were men and 19 were women.8 samples were found NoV positive among the 13 samples when detected by real-time PCR. The sequence alignment showed that the nucleotide sequence homology between Jinshan08 and Jinshan12 strain which obtained sequencing signal was 100%. The phylogenetic analysis revealed that Jinshan08, Jinshan12 and GII.e/NV2634/BCN/Spain/2008 strains in the RdRp region were on the the same branch of evolutionary tree, the confidence level was 99%, and in the N/S region of the Capsid, 2 other strains and Lordsdal strain were in the same branch, the confidence level was 97%. It was confirmed that the acute gastroenteritis outbreak was caused by the new GII.4 NoV recombinant.

Tularemia outbreaks in Kayseri, Turkey: An evaluation of the effect of climate change and climate variability on tularemia outbreaks

The aim of this study was to evaluate the epidemiological characteristics of tularemia outbreak and the effect of climate variability on this outbreak in Kayseri. The outbreak places, infection dates, source of infection, and the number of cases were recorded and analyzed. This information was obtained from the Regional Public Health Department. Climate data were supplied by the Regional Meteorological Service. The first case in Sariz was recorded in 2005. Thereafter, 2 cases were reported in 2006 and 1 case in 2007. During 2010, 21 cases were recorded in 7 towns, 62 cases in 2011 and 27 cases in 2012. A total number of 110 cases were recorded in 12 out of 16 towns in Kayseri Province between 2010 and 2012. The majority of cases were seen in the north-eastern, east and south-eastern parts of Kayseri Province; located in higher altitudes (over 1000m from sea level). It was accepted that the outbreak was originated from water sources and was confirmed by few number of water samples collected from outbreak areas. Considering climate variations, the outbreak occurred between 1988 and 2009 during a dry, low humid, high temperature period after rainy season. A tularemia outbreak was observed between 2010 and 2012 with the initiation of rainy years. High temperature for a long period accompanied by low rainfall and low humidity may affect the vector's biology and initiate a tularemia outbreak in high plateaus in Kayseri Province and around.

Reemergencia de sarampión en la provincia de Guadalajara. ¿Es el momento de establecer nuevas estrategias para su eliminación?

BackgroundMeasles is a viral infection that was almost eradicated, but it is re-emerging in Spain and Europe in recent years. The aim of this study was to describe the microbiological, clinical and epidemiological characteristics of a measles outbreak that occurred in Guadalajara (Spain) from June to August 2012. MethodsA descriptive and retrospective study was conducted. A total of 117 samples (including serum, urine and pharyngeal swabs) from 52 patients were analyzed for measles. ResultsMeasles was diagnosed in 50 patients, 41 of them by microbiological diagnosis, and 9 by epidemiological link. The patients were grouped in four community outbreaks. No imported cases were observed. Positive IgM and positive CRP were detected in 25 patients, positive CRP only in 11 and positive IgM only in 5. The genotype D4 was identified in 13 patients and the genotype A in a post-vaccine case. The age groups most affected were adults between 20-34 years of age (38%) and younger than 15 months (26%). The large majority (86%) of patients were unvaccinated (44% Roma population, 27% younger than 15 months, 11% ideological reasons), 6% had one vaccine dose. The signs/symptoms were: rash and fever, 100%, cough, 82%, and conjunctivitis 50%. Almost one–third (32%) of patients were hospitalized, and 28% had complications. ConclusionsIt is very important to intensify the epidemiological surveillance of infections in the elimination phase. The increased incidence of measles was associated to unvaccinated pockets, presenting a challenge for Public Health Centers. These agencies should prepare strategies to obtain a higher vaccine coverage for the eradication of measles.

Epidemiology and Etiology Characteristics of Foodborne Outbreaks Caused by Vibrio parahaemolyticus During 2008–2010 in Guangdong Province, China

Vibrio parahaemolyticus infection has been considered the leading cause of bacterial illnesses mainly associated with seafood consumption in Guangdong province in China. In this study, epidemiological and etiological characteristics of 36 V. parahaemolyticus outbreaks that occurred from 2008 to 2010 in Guangdong province were analyzed; 284 strains involved were characterized by serotyping; virulence genes and 66 strains from four outbreaks therein were subtyped by pulsed-field gel electrophoresis (PFGE). Epidemiological evidence showed that 36% (13/36) of outbreaks were caused by food contamination, of which 84.6 % (11/13) were related to salted food, including viscera of pigs and cattle, meat, and vegetable salad. It was also indicated that 88.9% (32/36) of V. parahaemolyticus outbreaks appeared from June to September, 44.4% (16/36) of which occurred in canteens as well as 41.7% (15/36) in restaurants. As for the etiology, 31% (11/36) of outbreaks were caused by single serovar of strains, while 69% (25/36) were caused by multiserovars; O3:K6, O4:K8, O1:Kut, and O2:K3 were the dominant serovars. Among the 284 strains, 98.8% (254/257) of strains from patients were tdh-present and trh-absent, whereas 37.0% (10/27) from food were tdh-present. Cluster analysis of PFGE patterns demonstrated that strains in the same outbreak with identical serovar seemed to be diversified, whereas strains with various serovars could be closely related genetically. Moreover, cross-contamination between salted food and seafood was first confirmed by molecular subtyping in Guangdong, revealing that salted food might be a vital risk factor associated with V. parahaemolyticus outbreaks.

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.

Characteristics of a Canine Distemper Virus Outbreak in Dichato, Chile Following the February 2010 Earthquake.

Simple SummaryA disease outbreak in domestic dogs was reported by a coastal Chilean community following the February 2010 earthquake and tsunami. Using clinical exams and diagnostic testing, canine distemper virus was confirmed. Most dogs seen had never been vaccinated, and the majority of those with positive results were recorded in dogs less than two years of age. There were no facilities to contain or treat dogs locally, and no plan to shelter free-roaming dogs. This observational study demonstrates the great need for disaster preparedness planning in developing countries that includes companion animals.Following the earthquake and tsunami disaster in Chile in February 2010, residents of Dichato reported high morbidity and mortality in dogs, descriptions of which resembled canine distemper virus (CDV). To assess the situation, free vaccine clinics were offered in April and May. Owner information, dog history and signalment were gathered; dogs received physical examinations and vaccines protecting against CDV, and other common canine pathogens. Blood was collected to screen for IgM antibodies to CDV. In total, 208 dogs received physical exams and vaccines were given to 177. IgM antibody titres to CDV were obtained for 104 dogs. Fifty-four dogs (51.9%) tested positive for CDV at the cut off titre of >1:50, but a total of 91.4% of dogs had a detectable titre >1:10. Most of the positive test results were in dogs less than 2 years of age; 33.5% had been previously vaccinated against CDV, and owners of 84 dogs (42.2%) reported clinical signs characteristic of CDV in their dogs following the disaster. The presence of endemic diseases in dog populations together with poor pre-disaster free-roaming dog management results in a potential for widespread negative effects following disasters. Creation of preparedness plans that include animal welfare, disease prevention and mitigation should be developed.

Molecular characteristics of acute gastroenteritis outbreaks caused by norovirus, in Jiangsu province

To study both the epidemiologic and molecular characteristics of outbreaks caused by norovirus (NoV) with its variants, in Jiangsu. 67 specimens from seven gastroenteritis outbreaks were collected from October 2012 to March 2013 in Jiangsu. NoV gene group was detected by Real-Time RT-PCR. NoV portions of RdRp gene and VP1 gene were amplified under RT-PCR. Seven gastroenteritis outbreaks were caused by NoV. Among all the fecal specimens,45 (67.2%) showed positive to NoV G II. Study on the genotype was conducted through analyzing the nucleotide sequence of RdRp gene. Based on the RdRp region, 7 strains appeared to be G II, with 3 and 38 strains belonged to G II.4--Sydney variants. Results from phylogenetic analysis confirmed that 38 variants shared 99% identity with G II.4--Sydney. We also amplified the VP1 genes from 6 variants and comparing with 9 epidemic strains on the sequence amino acid sequence. All the strains showed mutation in amino acid sequence at some key sites which were closely related to the forming of neutralizing epitopes. The short interval periods between all 7 NoV outbreaks with identical viral strain indicated the emergence of a new NoV variant in Jiangsu province,that had caused a number of epidemics abroad. Results from our study suggested that the development of monitoring programs on this novel G II.4--Sydney variant should be a part of the NoV surveillance in Jiangsu province or even in the country.

H1N1 pandemic: clinical and epidemiologic characteristics of the Canadian pediatric outbreak

Canada was one of the first countries affected by the 2009 influenza H1N1 pandemic with two waves – one from May to June and one from October to December. The 2009 influenza H1N1 pandemic had many unique features when compared with seasonal influenza, including the following: more than half of the affected people were children; asthma was the most significant risk factor for hospital admission; and Aboriginal and pregnant women had a higher risk of hospital admission and complications. Antiviral therapy was widely used but data did not show any effect on the pediatric population. Outbreak spread was possibly promoted from child–child and child–adult contact, and therefore the vaccination campaign targeted the pediatric population and achieved good coverage among young children (57%). Vaccination efficacy was difficult to test because of the vaccination delay. Improvement in models of prevention and treatment are urgently needed to prepare for the possible future pandemics.