Implementation Of Control Measures Research Articles

Reaching new lands: Updating the distribution of Angiostrongylus cantonensis in South America with the first record in Argentina.

Angiostrongylus cantonensis, commonly known as the rat lungworm, is a metastrongyloid nematode found primarily not only in tropical and subtropical regions but also in temperate areas and considered the leading cause of eosinophilic meningitis in humans. Synanthropic rodents such as Rattus norvegicus and Rattus rattus are the most frequent definitive hosts of this parasite. The presence of this parasite was detected in the pulmonary arteries of three specimens of R. norvegicus in the city of Buenos Aires representing the species' southernmost known record in natural hosts. Species confirmation was achieved through partial sequences of 18S and COI genes. By comparing the COI gene sequences with those available in GenBank through the construction of a haplotype network, we obtained that the analysed specimen presents high similarity with those reported in Japan and Southeast Asia. All infected rats were captured in an area surrounding a port with significant import and export activity, suggesting that A. cantonensis may have been introduced through commercial ships. Specifically, the parasite was detected in a neighbourhood with vulnerable socio-economic conditions and in a nature reserve, which exhibit biotic and abiotic characteristics conducive to sustaining high-density rat populations, scattered waste, areas of spontaneous vegetation, debris accumulation and flooded areas or lagoons offering suitable habitats for intermediate hosts such as snails. Thus, the close proximity of the port to these sites creates a favourable ecological context for the establishment of A. cantonensis. This study shows the need to conduct research to detect A. cantonensis in non-endemic areas but with the characteristics that promote its arrival and development of its life cycle in order to implement control measures to prevent expansion of this parasite and its transmission to humans and other animals.

Qualitative system dynamics modelling to support the design and implementation of tuberculosis infection prevention and control measures in South African primary health care facilities.

Tuberculosis infection prevention and control (TB IPC) measures are a cornerstone of policy, but measures are diverse and variably implemented. Limited attention has been paid to the health system environment which influences successful implementation of these measures. We used qualitative system dynamics and group-model-building methods 1) develop a qualitative causal map of the interlinked drivers of Mycobacterium tuberculosis (Mtb) transmission in South African primary health care facilities which in turn, helped us to 2) identify plausible IPC interventions to reduce risk of transmission. Two one-day participatory workshops were held in 2019 with policy- and decision-makers at national and provincial level, and patient advocates and health professionals at clinic and district level. Causal loop diagrams were generated by participants and combined by investigators. The research team reviewed diagrams to identify the drivers of nosocomial transmission of Mtb in primary health care facilities. Interventions proposed by participants were mapped onto diagrams to identify anticipated mechanisms of action and effect. Three systemic drivers were identified: 1) Mtb nosocomial transmission is driven by bottlenecks in patient flow at given times; 2) IPC implementation and clinic processes are anchored within a staff "culture of nominal compliance"; and 3) limited systems-learning at policy level inhibits effective clinic management and IPC implementation. Interventions prioritised by workshop participants included infrastructural, organisational, and behavioural strategies that target three areas: 1) improve air quality; 2) improve use of personal protective equipment; and 3) reduce the number of individuals in the clinic. In addition to core mechanisms, participants elaborated specific additional enablers that would help sustain implementation. Qualitative system dynamics modelling (SDM) methods allowed us to capture stakeholder views and potential solutions to address the problem of sub-optimal TB IPC implementation. The participatory elements of SDM facilitated problem-solving and inclusion of multiple factors frequently neglected when considering implementation.

A detailed methodology for estimating health-related hazards of workplace exposure to indoor formaldehyde vapours

A comprehensive risk assessment method was applied to examine the risks associated with airborne formaldehyde occupational exposure among hospital laboratory staff. The method assessed exposure levels and health impacts by integrating area and personal air sampling, biological monitoring, and self-reported health data. Samples were collected from 74 workplaces across various departments using NIOSH method 3500 and were analyzed via UV-vis spectrophotometry. The data showed significant differences in exposure levels between departments (p≤0.05) and confirmed the efficacy of the method in identifying risk differences. Despite average personal exposure levels being measured lower than occupational limits, individual assessments indicated that some participants surpassed these limits, emphasizing the necessity of personal monitoring for workers with higher risks. The high prevalence of respiratory symptoms, such as cough and wheezing among staff, indicated the need for further investigation and targeted interventions. Although estimated cancer and non-cancer risks were within safe thresholds, the study emphasized the importance of continuous exposure monitoring and the implementation of effective control measures in hospital laboratory departments with formaldehyde emission. This integrated method improved the reliability and generalizability of formaldehyde exposure risk assessments and aided in the development of safe occupational health practices.•The method integrated personal and area sampling with advanced calibration for precise occupational exposure evaluation in laboratories.•The method used of biomarkers to assess formaldehyde absorption in the body estimating both cancerous and non-cancerous health risks associated with occupational exposure.•Addressed traditional method limitations and integrated risk components to improve data reliability for workplace safety and health risk management.

Using species population structure to assist in management and decision-making in the fight against invasive species: The case of the Atlantic blue crab Callinectes sapidus

The blue crab Callinectes sapidus Rathbun, 1896 is an invasive species in the Mediterranean, with a remarkable ability to adapt to various habitats, and thereby having significant impacts on biodiversity and artisanal fishing activities. Currently, fishing is a measure being considered to control blue crab populations in invaded sites. However, it is necessary to understand the temporal structure of blue crab populations (e.g., growth, reproduction, sexual maturity) to determine specific periods when control measures need to be implemented. Considering the species' ability to adapt to various habitats, it is crucial to evaluate how temperature and salinity influence population structure. In this study, we present fishers-dependent monitoring on the temporal population structure of blue crabs in two lagoons in Corsica (France) over 12 months. Through this approach, we provide new information that can assist in decision-making for the implementation of control measures. Even though these two lagoons are geographically close, blue crab populations showed differences, particularly in terms of sexual maturity. Specimens from Biguglia mature later (males: 16.16 cm; females: 16.79 cm) than those in the Palo Lagoon (males: 14.38 cm; females: 13.86 cm). Seasonal size distribution also showed differences between the lagoons and within the same lagoon between males and females. Temperature and salinity had a significant effect on the monthly relationship between carapace width and wet weight (referred to here as growth rate) for males and females and between the lagoons. In the Biguglia Lagoon, the higher the temperature, the greater the growth rate over a wide salinity window (16–30 psu); for females, the environmental window was restricted (temperature: 20–30°C; salinities > 16 psu). The dynamics differed in the Palo Lagoon, with a more restricted high growth rate window for males, and females showed a much wider window, with high growth rates over the entire temperature and salinity range. By employing blue crab’s populations monitoring along with environmental parameters, we were able to determine how the environment influenced the blue crab’s population structure, thus identifying periods conducive to species control. The most effective strategy would undoubtedly be to eliminate females before their period of sexual maturity and copulation ensue. In our case, this would involve intensive control in summer for Biguglia and in spring for Palo. These recommendations have been translated into operations to be implemented as part of the "Territorial Plan for Combating the Blue Crab (Callinectes sapidus) in Corsica (2024–2027)".

Development of a triplex RT-RAA-LFA assay for the rapid differential diagnosis of porcine epidemic diarrhea virus, porcine deltacoronavirus and transmissible gastroenteritis virus

Porcine epidemic diarrhea virus (PEDV), porcine deltacoronavirus (PDCoV) and transmissible gastroenteritis virus (TGEV) are three clinically common coronaviruses causing diarrhea in pigs, with indistinguishable clinical signs and pathological changes. Rapid, portable and reliable differential diagnosis of these three pathogens is crucial for the prompt implementation of appropriate control measures. In this study, we developed a triplex nucleic acid assay that combines reverse transcription recombinase-aided amplification (RT-RAA) with lateral flow assay (LFA) by targeting the most conserved genomic region in the ORF1b genes of PEDV, PDCoV and TGEV. The entire detection process of the triplex RT-RAA-LFA assay included 10-min nucleic acid amplification at 42 °C and 5-min visual LFA readout at room temperature. The assay could specifically differentiate PEDV, PDCoV and TGEV without cross-reaction with any other major swine pathogens. Sensitivity analysis showed that the triplex RT-RAA-LFA assay was able to detect the viral RNA extracted from the spiked fecal samples with the minimum of 1 × 100 TCID50 PEDV, 1 × 104 TCID50 PDCoV, and 1 × 102 TCID50 TGEV per reaction, respectively. Further analysis showed that the 95 % detection limit (LOD) of triplex RT-RAA-LFA for PEDV, PDCoV, and TGEV were 22, 478, and 205 copies of recombinant plasmids per reaction, respectively. The diagnostic performance of triplex RT-RAA-LFA was compared with that of PEDV, PDCoV and TGEV respective commercial real-time RT-PCR kits by testing 114 clinical rectal swab samples in parallel. The total diagnostic coincidence rates of triplex RT-RAA-LFA with real-time RT-PCR kits of PEDV, PDCoV and TGEV were 100 %, 99.1 % and 99.1 %, respectively, and their Kappa values were 1.00, 0.958 and 0.936, respectively. Collectively, the RT-RAA-LFA assay is a powerful tool for the rapid, portable, visual, and synchronous differential diagnosis of PEDV, PDCoV, and TGEV.

Seroprevalence of B. pertussis infection and the changes of specific antibody levels in health care workers during the first two years of COVID-19 in Wuhu, China

BackgroundThe reported number of pertussis cases declined after the implementation of COVID-19 prevention and control measures, however, the burden of pertussis among adults in China remains largely unknown. Additionally, the waning of natural antibody level has also rarely been assessed. MethodsA total of 762 healthcare workers (HCWs) who had underwent the health examinations in 2021 and 2022 were included. Serum anti-PT IgG and IgA levels were determined by ELISA. Recent B. pertussis infection was defined as anti-PT IgG ≥100 IU/ml and/or anti-PT IgA ≥10 IU/ml. ResultsIn 2021, the seroprevalence of recent B. pertussis infection was 10.1 %, and those HCWs in outpatient department had a higher percentage (18.6 %), and geometric mean concentration (GMC) (6.3 IU/ml) than those in other departments. This seroprevalence decreased to 2.4 % in 2022, although the difference remained significant. In the 77 subjects with recent B. pertussis infection in 2021, anti-PT IgG was undetectable in 18 cases the following year. Majority (68/76) of the subjects with anti-PT IgA ≥10 IU/ml in 2021 no longer had detected this antibody in 2022. Among 95 pertussis cases, approximately 60.0 % of cases reported no history of cough. Among those with a documented cough history, 36 cases with suspected pertussis courses who had never been diagnosed. Prolonged cough with nocturnal exacerbation (29/38) was the most commonly reported clinical symptom, and whoop was confirmed in six cases. Uroclepsia and syncopes during the cough attacks were reported by three and one subjects, respectively. One case presented with subconjunctival hemorrhage and tensionic purpura during the course. ConclusionsThe results suggested a high prevalence of B. pertussis infection among HCWs. The presence of unrecognized adult pertussis cases and the rapid waning of antibody indicate the need to improve clinical management for suspected pertussis in adults, and to updated immunization schedule after childhood program.

Impact of the COVID-19 Pandemic on Influenza Hospital Admissions and Deaths in Wales: Descriptive National Time Series Analysis.

The COVID-19 pandemic and the ensuing implementation of control measures caused widespread societal disruption. These disruptions may also have affected community transmission and seasonal circulation patterns of endemic respiratory viruses. We aimed to investigate the impact of COVID-19-related disruption on influenza-related emergency hospital admissions and deaths in Wales in the first 2 years of the pandemic. A descriptive analysis of influenza activity was conducted using anonymized pathology, hospitalization, and mortality data from the Secure Anonymised Information Linkage Databank in Wales. The annual incidence of emergency hospitalizations and deaths with influenza-specific diagnosis codes between January 1, 2015, and December 31, 2021, was estimated. Case definitions of emergency hospitalization and death required laboratory confirmation with a polymerase chain reaction test. Trends of admissions and deaths were analyzed monthly and yearly. We conducted 2 sensitivity analyses by extending case definitions to include acute respiratory illnesses with a positive influenza test and by limiting admissions to those with influenza as the primary diagnosis. We also examined yearly influenza testing trends to understand changes in testing behavior during the pandemic. We studied a population of 3,235,883 Welsh residents in 2020 with a median age of 42.5 (IQR 22.9-61.0) years. Influenza testing in Wales increased notably in the last 2 months of 2020, and particularly in 2021 to 39,720 per 100,000 people, compared to the prepandemic levels (1343 in 2019). The percentage of influenza admissions matched to an influenza polymerase chain reaction test increased from 74.8% (1890/2526) in 2019 to 85.2% (98/115) in 2021. However, admissions with a positive test per 100,000 population decreased from 17.0 in 2019 to 2.7 and 0.6 in 2020 and 2021, respectively. Similarly, deaths due to influenza with a positive influenza test per 100,000 population decreased from 0.4 in 2019 to 0.0 in 2020 and 2021. Sensitivity analyses showed similar patterns of decreasing influenza admissions and deaths in the first 2 years of the COVID-19 pandemic. Nonpharmaceutical interventions to control COVID-19 were associated with a substantial reduction in the transmission of the influenza virus, with associated substantial reductions in hospital cases and deaths observed. Beyond the pandemic context, consideration should be given to the role of nonpharmaceutical community-driven interventions to reduce the burden of influenza.

Bridging Linguistic Gaps: Developing a Greek Text Simplification Dataset

Text simplification is crucial in bridging the comprehension gap in today’s information-rich environment. Despite advancements in English text simplification, languages with intricate grammatical structures, such as Greek, often remain under-explored. The complexity of Greek grammar, characterized by its flexible syntactic ordering, presents unique challenges that hinder comprehension for native speakers, learners, tourists, and international students. This paper introduces a comprehensive dataset for Greek text simplification, containing over 7500 sentences across diverse topics such as history, science, and culture, tailored to address these challenges. We outline the methodology for compiling this dataset, including a collection of texts from Greek Wikipedia, their annotation with simplified versions, and the establishment of robust evaluation metrics. Additionally, the paper details the implementation of quality control measures and the application of machine learning techniques to analyze text complexity. Our experimental results demonstrate the dataset’s initial effectiveness and potential in reducing linguistic barriers and enhancing communication, with initial machine learning models showing promising directions for future improvements in classifying text complexity. The development of this dataset marks a significant step toward improving accessibility and comprehension for a broad audience of Greek speakers and learners, fostering a more inclusive society.

Interactive and lag effects of environmental factors on the density of schistosome-transmitting Oncomelania hupensis: A twelve-year monthly repeated survey.

Schistosomiasis is a significant public health threat, and Oncomelania hupensis is the only intermediate host for schistosoma japonicum. We conducted 12-year monthly repeated surveys to explore the interactive and lag effects of environmental factors on snail density and to monitor their long-term and seasonal trends in a bottomland around the Dongting Lake region in China. Relevant environmental data were obtained from multiple sources. A Bayesian kernel machine regression model and a Bayesian temporal model combined with a distributed lag model were constructed to analyze interactive and lag effects of environmental factors on snail density. The results indicated the average annual snail density in the study site exhibited an increasing and then decreasing trend, peaking in 2013. Snail densities were the highest in October and the lowest in January in a year. Normalized Difference Vegetation Index (NDVI) and water level were the most effective predictors of snail density, with potential interactions among temperature, precipitation, and NDVI. The mean minimum temperature in January, water level, precipitation and NDVI were positively correlated with snail density at lags ranging from 1 to 4 months. These findings could serve as references for relevant authorities to monitor the changing trend of snail density and implement control measures, thereby reducing the occurrence of schistosomiasis.

Cefiderocol-Based Regimen for Acinetobacter NDM-1 Outbreak.

Variable outcomes have been reported with cefiderocol in infections due to carbapenem-resistant Acinetobacter baumannii (CRAB). Nonetheless, it may be the only option for metallo-beta-lactamase-producing strains. We describe an outbreak of NDM-CRAB infections treated with cefiderocol. Thirty-eight patients were colonized and/or infected. Thirteen patients developed a systemic infection. A clinical cure was achieved in 10 (83%) patients, one VAP and 9 BSIs, at day 7. In vitro, the activity of cefiderocol does not appear to match in vivo effectiveness using currently available commercial tests. Despite high clinical cures, overall mortality remains high in severely ill patients. Cefiderocol may be considered in this specific setting, though the implementation of susceptibility tests and infection control measures is mandatory.

LAMP combined with Pyrococcus furiosus Argonaute for the ultrasensitive and highly specific point-of-care test platform for Listeria monocytogenes detection

Listeria monocytogenes is an important foodborne pathogen that causes serious infectious diseases in humans and animals. Rapid, accurate, and sensitive detection in the field is critical for the timely implementation of control measures and ensuring food safety. The study established a method that combines loop-mediated isothermal amplification (LAMP) technology and Pyrococcus furiosus Argonaute (PfAgo) reporter system, which can detect L. monocytogenes hly gene levels as low as 1.8 × 101 copies. To overcome the demands on instrumentation and equipment, lateral flow strip (LFS) technology was combined for the first time in a LAMP-PfAgo-based system to detect L. monocytogenes. The method was highly sensitive, with a limit of detection of 1.8 × 102copies, and specificity results showed no cross-reactivity with other pathogens. The performance of the method was comparable to that of real-time fluorescence quantitative PCR (qPCR) in the detection of 18 food origin samples. Moreover, the LAMP-PfAgo reaction was equipped a low-cost thin metal bath as a simple amplification device, allowing it to detect L. monocytogenes samples in shorter time, highlighting its potential as a portable, rapid, accurate, and visual nucleic acid assay. The method can facilitate the early detection of pathogenic infections and promoting food safety detection technologies.

Investigation of sliding mode dynamics and near-optimal controls for a reaction–diffusion population model in a polluted environment

In this paper, we present a reaction–diffusion population model developed for a polluted environment, and investigate the impact of different control measures on population-toxicant dynamics. Toxicant concentrations is taken as the reference to determine whether to implement control measures, and sliding mode dynamics are studied. The dynamical behaviors of each subsystem are discussed, and results show that model solutions ultimately approach either two endemic equilibria or the sliding equilibrium on a surface of discontinuity. Furthermore, we formulate the near-optimal control problem by minimizing the control cost while reducing the toxicant concentration. The sufficient and necessary conditions for the near-optimality are established using Ekeland’s variational principle and Hamiltonian function. The theoretical results are illustrated by numerical simulations.

Spatial source, simulating improvement, and short-term health effect of high PM2.5 exposure during mutation event in the key urban agglomeration regions in China

Air quality in China has significantly improved owing to the effective implementation of pollution control measures. However, mutation events caused by short-term spikes in PM2.5 in urban agglomeration regions continue to occur frequently. Identifying the spatial sources and influencing factors, as well as improving the prediction accuracy of high PM2.5 during mutation events, are crucial for public health. In this study, we firstly introduced discrete wavelet transform (DWT) to identify the mutation events with high PM2.5 concentration in the four key urban agglomerations, and evaluated the spatial sources for the polluted scenario using Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Additionally, DWT was combined with a widely used artificial neural network (ANN) to improve the prediction accuracy of PM2.5 concentration seven days in advance (seven-day forecast). Results indicated that mutation events commonly occurred in the northern regions during winter time, which were under the control of both short-range transportation of dirty airmass as well as negative meteorology conditions. Compared with the ANN model alone, the average band errors decreased by 9% when using DWT-ANN model. The average correlation coefficient (R) and root mean square error (RMSE) obtained using the DWT-ANN improved by 10% and 12% compared to those obtained using the ANN, indicating the efficiency and accuracy of simulating PM2.5, by combining the DWT and ANN. The short-term mortality during mutation events was then calculated, with the total averted all-cause, cardiovascular, and respiratory deaths in the four regions, being 4751, 2554, and 582 persons, respectively. A declining trend in prevented deaths from 2018 to 2020 demonstrated that the pollution intensity during mutation events gradually decreased owing to the implementation of the Three-Year Action Plan to Win the Blue Sky Defense War. The method proposed in this study can be used by policymakers to take preventive measures in response to a sudden increase in PM2.5, thereby ensuring public health.

Pathogenicity and molecular characterization of a GI-19 infectious bronchitis virus isolated from East China.

Infectious bronchitis virus (IBV) is responsible for avian infectious bronchitis, a disease prevalent in countries with intensive poultry farming practices. Given the presence of multiple genotypic strains in China, identifying the regionally dominant genotypes is crucial for the implementation of effective prevention and control measures. This study focuses on the IBV strain CK/CH/WJ/215, isolated from a diseased commercial chicken flock in China in 2021. The CK/CH/WJ/215 isolate was genetically characterized through complete S1 sequence analysis. Phylogenetic comparisons were made with prevalent vaccine strains (H120, LDT3-A, and 4/91). Glycosylation patterns in the S1 protein were also analyzed. Pathogenicity was assessed in 7-day-old specific-pathogen-free chicks, monitoring morbidity, mortality, and tissue tropisms. Phylogenetic analysis clustered the CK/CH/WJ/215 isolate within the GI-19 lineage. Identity with the vaccination strains H120, LDT3-A, and 4/91 was low (75.7%, 78.6%, and 77.5% respectively). Novel glycosylation sites at positions 138 and 530 were identified compared to H120 and LDT-A. The isolate demonstrated nephropathogenic characteristics, causing 100% morbidity and 73.3% mortality in SPF chicks, with broader tropisms in tissues including trachea, lungs, kidneys, and bursa of Fabricius. Comprehensive genetic and pathological investigations revealed significant differences between the CK/CH/WJ/215 isolate and common vaccine strains, including novel glycosylation sites and a strong multiorgan infective capability. These findings are crucial for understanding the evolutionary dynamics of IBV and developing more effective prevention and control strategies.

Tritrichomonas foetus testing in bulls.

To provide a video tutorial on how to perform preputial scraping for the testing of Tritrichomonas foetus in bulls. Postpubertal bulls. A preputial scraping device is inserted in the prepuce, and back-and-forth scraping movements are made to collect smegma and T foetus organisms. The sample is placed in an appropriate media and prepared for shipment to the diagnostic laboratory. Preputial sampling is an effective method for diagnosing T foetus in infected bulls. Bulls are the primary carriers of T foetus, a protozoan parasite responsible for bovine trichomoniasis. By sampling and testing bulls, veterinarians can identify infected animals and implement control measures to prevent the spread of the disease within herds. Trichomoniasis can lead to significant reproductive problems in cattle, including infertility, embryonic death, and abortions. Sampling bulls allows for the detection of infection, enabling prompt intervention to protect the reproductive health of the entire herd. Trichomoniasis outbreaks can result in substantial economic losses for cattle producers due to reduced conception rates, increased calving intervals, and decreased calf crops. Sampling bulls helps to mitigate these losses by identifying and removing infected animals from the breeding pool, thereby minimizing the spread of the disease and its associated reproductive inefficiencies. In many regions, T foetus testing in bulls is a regulatory requirement for cattle movement and trade. Sampling bulls and obtaining negative test results are often necessary for obtaining health certificates and complying with interstate or international movement regulations.

Vaccination and transportation intervention strategies for effective pandemic control

The COVID-19 pandemic highlighted the pivotal role of transportation-related controls and vaccination in mitigating widespread infections. However, the substantial costs associated with these interventions necessitate a nuanced equilibrium between control measures and infection risks. This study, driven by the recognition of spatial heterogeneities in mobility networks and epidemic vulnerability, presents an optimal control framework for two control measures—vaccine distribution and transportation restrictions—within a metapopulation structure. The overarching goal is to minimize the total costs derived from the implementation of control measures and health and opportunity loss from infection. Our findings highlight the effectiveness of transportation control and vaccine distribution in reducing both total costs and infection rates. Notably, the efficacy of these control measures exhibits regional variations, and the simultaneous implementation of both measures emerges as the most effective and economically viable strategy. The synergy effect between vaccine distribution and transportation restrictions is also a key observation in our simulations, showcasing their complementary roles in pandemic control. By considering the spatial nuances of mobility networks and infection vulnerability, this framework provides a flexible and region-specific strategy to optimize the allocation of resources for pandemic control, ultimately striking a balance between efficacy and economic feasibility.

Panton-Valentine leucocidin gene in methicillin resistant Staphylococcus aureus isolated from tertiary care hospital in Nepal.

Methicillin-resistant Staphylococcus aureus (MRSA) expresses the Panton-Valentine leukocidin (PVL) virulence gene, which is associated with community and hospital-acquired severe MRSA infections. The objective of this study was to determine the prevalence and antibiotic susceptibility profile with a focus on the presence of the PVL gene among MRSA isolates in healthcare settings. A total of 1,207 clinical specimens and 304 hospital environment swabs were collected in a tertiary care hospital in Nepal, and investigated following basic microbiological techniques. S. aureus was confirmed with the coagulase test. An antibiotic susceptibility test (AST) was performed by the Kirby-Bauer method and screening for MRSA was carried out by the cefoxitin disc diffusion method guided by the Clinical and Laboratory Standards Institute (CLSI), 2020. DNA was extracted and used in a polymerase chain reaction (PCR) to detect mecA and PVL genes. Of the 1,511 samples, 45 (2.9%) S. aureus (23 clinical and 22 environmental) were isolated. Among them, 69.6% (16/23) and 27.3% (6/22) were MRSA in clinical and environmental isolates, respectively. Twelve (52.2%) clinical isolates and seven (31.8%) environmental isolates were multidrug resistant. The majority of isolates were susceptible to vancomycin and linezolid. The PVL gene was detected in 18.2% (n = 4/22) of the MRSA isolates, of which three were from clinical sources and one was from an environmental swab. The prevalence of MRSA, and PVL-producing S. aureus were higher in the hospital setting. Hence, immediate and urgent implementation of infection control and sanitation measures are needed in the hospital.

Identifying highly connected sites for risk-based surveillance and control of cucurbit downy mildew in the eastern United States.

Surveillance is critical for the rapid implementation of control measures for diseases caused by aerially dispersed plant pathogens, but such programs can be resource-intensive, especially for epidemics caused by long-distance dispersed pathogens. The current cucurbit downy mildew platform for monitoring, predicting and communicating the risk of disease spread in the United States is expensive to maintain. In this study, we focused on identifying sites critical for surveillance and treatment in an attempt to reduce disease monitoring costs and determine where control may be applied to mitigate the risk of disease spread. Static networks were constructed based on the distance between fields, while dynamic networks were constructed based on the distance between fields and wind speed and direction, using disease data collected from 2008 to 2016. Three strategies were used to identify highly connected field sites. First, the probability of pathogen transmission between nodes and the probability of node infection were modeled over a discrete weekly time step within an epidemic year. Second, nodes identified as important were selectively removed from networks and the probability of node infection was recalculated in each epidemic year. Third, the recurring patterns of node infection were analyzed across epidemic years. Static networks exhibited scale-free properties where the node degree followed a power-law distribution. Betweenness centrality was the most useful metric for identifying important nodes within the networks that were associated with disease transmission and prediction. Based on betweenness centrality, field sites in Maryland, North Carolina, Ohio, South Carolina and Virginia were the most central in the disease network across epidemic years. Removing field sites identified as important limited the predicted risk of disease spread based on the dynamic network model. Combining the dynamic network model and centrality metrics facilitated the identification of highly connected fields in the southeastern United States and the mid-Atlantic region. These highly connected sites may be used to inform surveillance and strategies for controlling cucurbit downy mildew in the eastern United States.

Detection of Enteric Viruses in Children under Five Years of Age before and after Rotavirus Vaccine Introduction in Manhiça District, Southern Mozambique, 2008-2019.

Enteric viruses are the leading cause of diarrhoea in children <5 years. Despite existing studies describing rotavirus diarrhoea in Mozambique, data on other enteric viruses remains scarce, especially after rotavirus vaccine introduction. We explored the prevalence of norovirus GI and GII, adenovirus 40/41, astrovirus, and sapovirus in children <5 years with moderate-to-severe (MSD), less severe (LSD) diarrhoea and community healthy controls, before (2008-2012) and after (2016-2019) rotavirus vaccine introduction in Manhiça District, Mozambique. The viruses were detected using ELISA and conventional reverse transcription PCR from stool samples. Overall, all of the viruses except norovirus GI were significantly more detected after rotavirus vaccine introduction compared to the period before vaccine introduction: norovirus GII in MSD (13/195, 6.7% vs. 24/886, 2.7%, respectively; p = 0.006) and LSD (25/268, 9.3% vs. 9/430, 2.1%, p < 0.001); adenovirus 40/41 in MSD (7.2% vs. 1.8%, p < 0.001); astrovirus in LSD (7.5% vs. 2.6%, p = 0.002); and sapovirus in MSD (7.1% vs. 1.4%, p = 0.047) and controls (21/475, 4.4% vs. 51/2380, 2.1%, p = 0.004). Norovirus GII, adenovirus 40/41, astrovirus, and sapovirus detection increased in MSD and LSD cases after rotavirus vaccine introduction, supporting the need for continued molecular surveillance for the implementation of appropriate control and prevention measures.

Genomic evolution of ST228 SCCmec-I MRSA 10 years after a major nosocomial outbreak.

In this study, we investigated the genomic changes in a major methicillin-resistant Staphylococcus aureus (MRSA) clone following a significant outbreak at a hospital. Whole-genome sequencing of MRSA isolates was utilized to explore the genomic evolution of post-outbreak MRSA strains. The epidemicity of the clone declined over time, coinciding with the introduction of multimodal infection control measures. A genome-wide association study (GWAS) identified multiple genes significantly associated with either high or low epidemic success, indicating alterations in mobilome, virulence, and defense mechanisms. Random Forest models pinpointed a gene related to fibrinogen binding as the most influential predictor of epidemicity. The decline of the MRSA clone may be attributed to various factors, including the implementation of new infection control measures, single nucleotide polymorphisms accumulation, and the genetic drift of a given clone. This research underscores the complex dynamics of MRSA clones, emphasizing the multifactorial nature of their evolution. The decline in epidemicity seems linked to alterations in the clone's genetic profile, with a probable shift towards decreased virulence and adaptation to long-term carriage. Understanding the genomic basis for the decline of epidemic clones is crucial to develop effective strategies for their surveillance and management, as well as to gain insights into the evolutionary dynamics of pathogen genomes.