Disease Control Strategies Research Articles

Unlocking the potential: Cinnamomum cassia (L.) D. Don aqueous extracts as natural defenders against MSRV in largemouth bass aquaculture

Aquatic viral diseases pose significant threats to aquaculture, necessitating the exploration of effective preventive measures. In this study, we evaluated the antiviral potential of Cinnamomum cassia (L.) D. Don (CCD) aqueous extracts against Micropterus salmoides rhabdovirus (MSRV) in largemouth bass aquaculture. Initially, twelve plant extracts were screened for antiviral activity against MSRV, revealing that CCD extracts at 100 mg/L concentration significantly inhibited MSRV proliferation in vitro. Further dose-response analysis revealed a concentration-dependent antiviral effect of CCD extracts, with higher concentrations demonstrating increased efficacy against MSRV. Subsequent investigations focused on the protective effects of CCD extracts on MSRV-infected cells. At a concentration of 63 mg/L, CCD extracts significantly reduced MSRV titers, preventing the onset of cytopathic effects (CPE) in cells. Fluorescence and transmission electron microscopy further illustrated the protective effects of CCD extracts on cellular morphology. MSRV-infected cells treated with CCD exhibited preserved cell morphology akin to normal cells, contrasting with the typical apoptotic features observed in untreated infected cells. Additionally, dietary supplementation of CCD extracts in largemouth bass demonstrated notable benefits. Fish fed with CCD extracts exhibited increased survival rates when infected with MSRV, with a 26 % higher survival rate compared to the virus-only group. Furthermore, CCD supplementation enhanced the expression of interferon-gamma (IFNγ), indicating improved immune responses in largemouth bass. Moreover, immersion of CCD extracts in water showed partial inhibition of horizontal MSRV transmission, effectively reducing viral spread and mitigating disease risks in fish populations. These findings highlight the potential of CCD aqueous extracts as feed additives for combating MSRV in aquaculture, showcasing their promising application prospects in disease prevention and control strategies.

Dynamical and optimal control analysis of lymphatic filariasis and buruli ulcer co-infection

This study delves into the dynamics of lymphatic filariasis and buruli ulcer coinfection, two overlooked yet impactful tropical diseases. With lymphatic filariasis, commonly referred to as elephantiasis, and buruli ulcer, a chronic affliction caused by mycobacterium ulcerans, both posing significant health challenges, understanding their interaction is crucial. Utilizing a mathematical model, this research aims to analyze the dynamics of this coinfection, elucidating its complexities. The study establishes the local asymptotic stability of the disease-free equilibrium and calculates the basic reproduction number using the next generation matrix. It uncovers transcritical and backward bifurcation phenomena within the model. Additionally, the integration of time-dependent controls enables the exploration of optimal disease management strategies. Numerical simulations highlight the efficacy of employing a comprehensive approach, utilizing all available controls simultaneously, as the most effective strategy for disease control. These findings underscore the importance of integrated interventions in combating lymphatic filariasis and buruli ulcer coinfection, offering valuable insights for public health policymakers and practitioners.

Pylore Krishnaier Rajagopalan: Pioneer in Kyasanur Forest Disease Research and His Contributions to Zoonotic Disease Studies.

Pylore Krishnaier Rajagopalan was a distinguished public health expert who made significant breakthroughs in the research of Kyasanur forest disease (KFD), a prevalent tick-borne viral ailment in South India. His extensive research on KFD provided vital insights into the impact of the disease on public health and considerably advanced our knowledge of it. Rajagopalan's work also encompasses the study of zoonotic diseases, where he made substantial contributions to our understanding of their epidemiology and control. His research on KFD was instrumental in comprehending the disease transmission dynamics, clinical manifestations, and control strategies, resulting in improved management practices in regions where the disease is endemic. Rajagopalan's contributions have had a long-lasting impact on public health practices, as his work has influenced both scientific research and public health policies. The enduring effects of his work can be observed in the enhanced disease surveillance, outbreak response, and comprehension of zoonotic disease dynamics, which will continue to inform contemporary public health practices.

Effects of Atractylodes macrocephala polysaccharide on growth performance, serum biochemical indexes, and intestinal microflora of largemouth bass (Micropterus salmoides)

IntroductionAs the aquaculture industry intensifies to enhance production efficiency and capacity, the risk of disease outbreaks in high-density systems, such as those for largemouth bass, has escalated. This necessitates the exploration of novel strategies for disease prevention and control. Studies have shown that Atractylodes macrocephala polysaccharide (AMP) possesses the functions of promoting growth and enhancing immune capacity, making it a potential feed additive in animal production.MethodsThis study aimed to assess the impact of AMP on the growth performance, serum biochemical indices, and intestinal flora structure of largemouth bass. A total of 360 healthy largemouth bass (mean weight: 15.25 ± 1.29 g) were randomly assigned to four groups, each with three replicates. The groups were fed diets supplemented with 0% (Group D, control group), 0.4% (Group A), 0.8% (Group B), or 1.2% (Group C) AMP for 42 days.ResultsThe results showed that the addition of an appropriate amount of AMP in the feed significantly improved the weight gain rate (WGR) and specific growth rate (SGR) of largemouth bass, reduced the feed conversion ratio (FCR), and enhanced growth performance. AMP reduced the levels of AST and ALT, indicating a hepatoprotective effect on largemouth bass, with significant differences from the control group (P < 0.05). AMP also improved the intestinal microbiota composition of largemouth bass, positively affecting intestinal health. The analysis of intestinal microbiota revealed 1,288 amplicon sequence variants (ASVs) in the intestine of largemouth bass in Group B, dominated by Firmicutes and Bacteroidota. In contrast, Group C (1.2%) had 920 ASVs, with Fusobacteriota and Firmicutes as the major components, while the relative abundance of Firmicutes was lower, showing significant differences from the control Group D. The functional analysis of intestinal microbiota based on KEGG showed significant differences (P < 0.05) among the four groups in Carbon metabolism, Biosynthesis of amino acids, and Metabolic pathways.DiscussionThe study concludes that the inclusion of AMP at 0.8% – 1.2% in the feed can enhance the growth performance and intestinal health of largemouth bass, offering a promising strategy for disease prevention and control in intensive aquaculture settings.

Competition for nutrient niches within the apple blossom microbiota antagonizes the initiation of fire blight infection.

Changes in the plant microbiota composition are intimately associated with the health of the plant, but factors controlling the microbial community in flowers are poorly understood. In this study, we used apple flowers and fire blight as a model system to investigate the effects of floral microbiota and microbial competition on disease development and suppression. To compare changes in microbial flora with the RNA expression patterns of plants, the flower samples were collected in three different flowering stages (Bud, Popcorn, and Full-bloom). Using advanced sequencing technology, we analyzed the data and conducted both in vitro and in vivo experiments to validate our findings. Our results show that the Erwinia amylovora use arabinogalactan, which is secreted on the flowers, for early colonization of apple flowers. Pantoea agglomerans was more competitive for arabinogalactan than E. amylovora. Additionally, P. agglomerans suppressed the expression of virulence factors of E. amylovora by using arabinose, which is a major component of arabinogalactan, which induces virulence gene expression. The present data provide new insights into developing control strategies for diverse plant diseases, including fire blight, by highlighting the importance of nutrients in disease development or suppression.

The composition and unrevealed immune role of non-RLR DExD/H box RNA helicases in fish

The large superfamily of DExD/H box RNA helicases are involved in various life processes, such as RNA metabolism, transcriptional regulation, translation, tumorigenesis, cell cycle, and viral infection, and RIG-like receptors (RLRs) in the superfamily have been confirmed with crucial roles in viral infection by recognizing viral RNA. In this review, non-RLR DExD/H box RNA helicases were possibly summarized in relation with their composition and antiviral immune responses in teleost, with at least 52 genes in the helicase subfamily. Compared with mammals, most DExD/H box RNA helicases in teleost are conservatively present, but some are present in a fish-specific gene duplication manner or have been lost in evolution, which may imply the obvious compositional difference in fish. The comparison in innate immune roles of mammalian and teleost DExD/H box RNA helicases indicated that DDX3a, DDX3b, DHX9, DDX41, DDX43 are functional positively in anti-viral/bacterial immunity in fish, while DDX1, DDX3a, DDX5, DDX19, DDX23 negatively in the immunity. In the future, the composition, possible immune recognition, signalling and interaction with other immune pathways, as well as other biological functions are all of significant importance for research, which may contribute to the development of disease prevention and control strategies in aquaculture.

Influence of Climatic Factors on Rust Severity in Sorghum in Dharwad, Karnataka, India

Sorghum rust, caused by Puccinia purpurea, significantly reduces crop yield, affecting plant growth and grain quality. Understanding the impact of weather parameters on disease incidence is crucial for timely disease management, to enhance crop resilience and yield stability. This study aims to identify and quantify the relationship between weather parameters and the incidence of sorghum rust, to inform decision-making on disease management strategies. A comprehensive analysis was conducted utilizing 17 years of secondary data (2006-2022) sourced from the All India Coordinated Research Project (AICRP) on Sorghum and the Department of Agrometeorology at the Climate Model Intercomparison Project (CMIP), University of Agricultural Sciences (UAS), Dharwad. The study employed statistical methods, including Multiple Linear Regression (MLR) and Step-wise Regression, to model the dependence of rust disease incidence on independent variables such as precipitation, temperature, relative humidity, wind speed, radiation, and heat flux. The results revealed the MLR model explains 65.45% of the variation and the Step-wise Regression model identifies four critical parameters- relative humidity, heat flux, wind speed, and radiation that together accounted for 65.09% of the variation without exhibiting multicollinearity (Variance Inflation Factor values below 10). These findings enhance the understanding of environmental impacts on sorghum rust and can inform future agricultural management strategies for disease prediction and control.

Second International Avian Influenza and One Health Emerging Issues Summit

Dear esteemed guests, distinguished speakers, honorable delegates, and all participants worldwide Welcome to the International Avian Influenza and One Health Emerging Issues Summit, a premier event that brings together leading minds from across the globe to address some of the most pressing challenges in animal and human health. This year's Summit, held as a hybrid event in Fayetteville, Arkansas, USA, from September 30 to October 3, 2024, is dedicated to deepening our understanding of the intricate relationships between avian influenza and the broader One Health framework. As we gather in a time of unprecedented change and global interconnectedness, the Summit offers a unique platform for experts, researchers, policymakers, and stakeholders to explore the emerging issues that define the landscape of avian influenza. Our discussions will span the latest scientific research, innovative strategies for disease control, and the broader implications for public health, agriculture, and wildlife. Through a combination of in-person and virtual sessions, we aim to foster collaboration, share cutting-edge insights, and develop actionable solutions that can address the complex challenges at the intersection of animal, human, and environmental health. This Summit is not just a forum for knowledge exchange but a catalyst for forging the partnerships and policies necessary to protect global health in an increasingly interconnected world. We are excited to embark on this journey with you and look forward to the groundbreaking discussions and discoveries that will emerge over the next few days. Sincerely, Guillermo Tellez-Isaias Chairman

Comparative genomics and evolutionary analysis of dengue virus strains circulating in Pakistan.

Dengue fever virus (DENV) poses a significant public health risk in tropical and subtropical regions across the world. Although the dengue fever virus (DENV) exhibits significant genetic diversity and has the potential to evolve, there is a lack of comprehensive research on the comparative genomics and evolutionary dynamics of the virus in Pakistan. Phylogenetic analysis demonstrated the circulation of all four dengue virus serotypes (DENV-1, -2, -3, and -4) with prevalent genotypes III and V within DENV-1, cosmopolitan genotype within DENV-2, genotype III within DENV-3, and genotype I within DENV-4 during 2006-2014. Based on the complete envelope region, genome-wide residue signature and genetic diversity indicate that there is a high level of genetic diversity among DENV-1 strains, while DENV-3 strains exhibit the least genetic diversity. Comparative analysis of all four DENV serotypes revealed that certain codons in DENV-2 and -4 were subject to strong purifying selection, while a few codon sites in the envelope region showed evidence of positive selection. These findings provided valuable insights into the comparative genomics and evolutionary pattern of DENV strains reported from Pakistan. Whether those characteristics conferred a fitness advantage to DENV-1 genotypes within a specific geography and time interval warrants further investigations. The findings of the current study will contribute to tracking disease dynamics, understanding virus transmission and evolution, and formulating effective disease control strategies.

Optimal control strategies for infectious diseases with consideration of behavioral dynamics

We present a simple SVIR (susceptible, vaccinated, infected, recovered) model to analyze the spread of COVID‐19, incorporating the influence of the population's caution on the transmission rate, which is considered nonlinear in current number of infected. Demonstrating a positive bound solution confirms the model's biological relevance. Through a formula for the basic reproduction number, we explore the local asymptotic stability of the disease‐free equilibrium (DFE) and endemic equilibrium (EE), showing that the existence of the EE relies on the basic reproduction number. Furthermore, we establish the global stability of the DFE by constructing a Lyapunov function. We present an optimal control problem for vaccination, demonstrating the existence and uniqueness of the optimal strategy. Our simulations indicate that optimal vaccination is effective in reducing infections and costs. We also investigate the effect of integrating education into the model to underscore its importance in decreasing disease transmission rates and reducing the necessity for vaccine uptake.

The transmission dynamics of an infectious disease model in fractional derivative with vaccination under real data

The resurgence of monkeypox causes considerable healthcare risks needing efficient immunization programs. This work investigates the monkeypox disease dynamics in the UK, focusing on the impact of vaccination under real data. The key difficulty is to correctly predict the spread of the disease and evaluate the success of immunization efforts. We construct a mathematical model for monkeypox infection and extend it to the fractional case considering the Caputo derivative. The analysis ensures the positivity, boundedness, and uniqueness of the solution for the non-integer system. We conduct a local asymptotical stability analysis (LAS) at the disease-free equilibrium (DFE) D0, showing the result for R0<1. Additionally, we demonstrate the existence of multiple endemic equilibria and provide conditions for backward bifurcation, which are illustrated graphically. Using real case data from the UK, we estimate model parameters via the nonlinear least square method. Our results show that, without vaccination, R2≈0.8, whereas vaccination reduces it to R2v=0.48. We perform sensitivity analysis to identify key parameters influencing disease elimination, presenting the outcomes through graphs. To solve numerically the fractional model, we outline a numerical scheme and provide detailed results under various parameter assumptions. Our findings suggest that high vaccine efficacy, a low waning rate of the vaccines, and increased vaccination of the infected people can significantly reduce the future cases of monkeypox in the UK. The present study offers a comprehensive framework for monkeypox dynamics and informs public health strategies for effective disease control and prevention.

Metabolomic analysis revealed the inflammatory and oxidative stress regulation in response to Vibrio infection in Plectropomus leopardus.

Frequent outbreaks of infectious diseases in aquaculture have led to significant economic losses. The leopard coral grouper (Plectropomus leopardus) often suffers from vibriosis. Improving host immunity presents a superior strategy for disease control, with minimal side effects compared to the use of antibiotics, highlighting the necessity of exploring the mechanisms underlying the fish's response to pathogen infections. Here, we conducted a comparative metabolomic analysis on the livers of the P. leopardus infected with Vibrio harveyi. A total of 1124 differential metabolites (DMs) were identified, with 190, 218, 359, and 353 DMs being identified at 6, 12, 24, and 48 h post-infection (hpi), respectively. Then, based on the time series analysis, we found that the lipid metabolism pathways were modulated in response to the Vibrio infection, with an increase in the quantity of eicosanoids and gycerophospholipids (GPLs), as well as a decrease in the quantity of bile acids (BAs), vitamin D, and sex hormones. Furthermore, 13 enriched pathways involving 31 DMs were identified through KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analyses. We identified histamine, 15(S)-HpETE, and anandamide in the transient receptor potential (TRP) channels pathway, as well as (7S,8S)-DiHODE, 5S,8R-DiHODE, and 13(S)-HpODE in the linoleic acid (LA) metabolism pathway. The DM levels increased, which may be attributed to inflammation. The DMs in the thyroid hormone synthesis pathway were identified, and the contents of nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione (GSH) decreased, which may be crucial in antioxidants. Our findings highlighted the dynamic adjustments in lipid metabolism and the response to inflammation and oxidative stress during the infection of V. harveyi in P. leopardus. This study not only deepens our understanding of the metabolic underpinnings of fish immune responses but also lays the groundwork for research into functional metabolomics and mechanisms of disease resistance.

Discovery of functional PRRs for the fungal elicitor Xyn11/eix in Prunus fruit trees

Pattern-triggered immunity (PTI) is a critical defense mechanism employed by plants against pathogen attacks. This study explores the role of PTI induced by the Xyn11/eix fungal elicitor in two commercially valuable Rosaceae species, Prunus persica (peach) and Prunus avium (sweet cherry). Our findings demonstrate that Xyn11/eix triggers two specific defense responses: the increase in ethylene production and the induction of cell death. Furthermore, Xyn11/eix-mediated PTI significantly reduces the susceptibility to Botrytis cinerea infection in both species. The study reveals changes in gene expression patterns after Xyn11/eix treatment. Notably, ACO1 and SARDEF1 genes, involved in ethylene and salycilic acid biosynthesis, respectively, are upregulated in P. persica, but not in P. avium at the time point analyzed. This result suggests a potential role for the ethylene and salicylic acid signaling in Xyn11/mix-mediated PTI in P. persica. Additionally, the research identified functional orthologues of LeEIX2, the receptor for Xyn11/eix in Solanum lycopersicum, within both Prunes genomes. Altogether, these results suggest a remarkable functional convergence between Rosaceae and Solanaceae plants in the Xyn11/eix mediated defense responses although not at the transcriptional level, and opens new avenues for developing novel disease control strategies for stone fruits.

The integrated genomic surveillance system of Andalusia (SIEGA) provides a One Health regional resource connected with the clinic

The One Health approach, recognizing the interconnectedness of human, animal, and environmental health, has gained significance amid emerging zoonotic diseases and antibiotic resistance concerns. This paper aims to demonstrate the utility of a collaborative tool, the SIEGA, for monitoring infectious diseases across domains, fostering a comprehensive understanding of disease dynamics and risk factors, highlighting the pivotal role of One Health surveillance systems. Raw whole-genome sequencing is processed through different species-specific open software that additionally reports the presence of genes associated to anti-microbial resistances and virulence. The SIEGA application is a Laboratory Information Management System, that allows customizing reports, detect transmission chains, and promptly alert on alarming genetic similarities. The SIEGA initiative has successfully accumulated a comprehensive collection of more than 1900 bacterial genomes, including Salmonella enterica, Listeria monocytogenes, Campylobacter jejuni, Escherichia coli, Yersinia enterocolitica and Legionella pneumophila, showcasing its potential in monitoring pathogen transmission, resistance patterns, and virulence factors. SIEGA enables customizable reports and prompt detection of transmission chains, highlighting its contribution to enhancing vigilance and response capabilities. Here we show the potential of genomics in One Health surveillance when supported by an appropriate bioinformatic tool. By facilitating precise disease control strategies and antimicrobial resistance management, SIEGA enhances global health security and reduces the burden of infectious diseases. The integration of health data from humans, animals, and the environment, coupled with advanced genomics, underscores the importance of a holistic One Health approach in mitigating health threats.

A Review of the Latest Control Strategies for Mosquito-Borne Diseases.

Mosquito-borne diseases are persistent and potentially severe posing a threat to global pandemic preparedness. The risk of mosquito-borne virus transmission is rapidly increasing due to the unprecedented spread of viruses such as dengue and chikungunya, the disruption of global mosquito-borne disease control efforts following the emergence of coronavirus diseases 2019 (COVID-19) in 2019, global warming, and human activities. To address this global challenge, various innovative mosquito control technologies are being developed worldwide. This paper summarizes the latest advances in mosquito vector control, focusing on China's latest mosquito control strategies, to provide insights into implementing novel mosquito-borne disease control measures.

Comparison of chronic disease control strategies at different ages

As cardiovascular and cerebrovascular diseases (CVDs) in children are receiving increasing attention, the background is that CVDs at different age stages present different characteristics. Currently, some progress has been made in age-specific targeted therapeutic studies, but the refinement and optimisation of the overall treatment strategy still needs to be deepened. The research gap lies in the lack of a comprehensive and systematic comparison of treatment strategies for different age groups. This paper have analysed the differences and commonalities of CVD treatment strategies in different age groups, and obtained the relevant results of optimised strategies in each age group. Treatment for children must take into account the effects on growth and development, adolescents need to focus on prevention and correction, and the elderly require comprehensive management. This is of great significance in improving the treatment effect of CVD in children and provides a comprehensive reference for future studies, but the long-term effect assessment and individual difference response are still not fully resolved, and future studies can focus on further exploration in these directions.

Exploring the Landscape of Fractional-Order Models in Epidemiology: A Comparative Simulation Study

Mathematical models play a crucial role in evaluating real-life processes qualitatively and quantitatively. They have been extensively employed to study the spread of diseases such as hepatitis B, COVID-19, influenza, and other epidemics. Many researchers have discussed various types of epidemiological models, including deterministic, stochastic, and fractional order models, for this purpose. This article presents a comprehensive review and comparative study of the transmission dynamics of fractional order in epidemiological modeling. A significant portion of the paper is dedicated to the graphical simulation of these models, providing a visual representation of their behavior and characteristics. The article further embarks on a comparative analysis of fractional-order models with their integer-order counterparts. This comparison sheds light on the nuances and subtleties that differentiate these models, thereby offering valuable insights into their respective strengths and limitations. The paper also explores time delay models, non-linear incidence rate models, and stochastic models, explaining their use and significance in epidemiology. It includes studies and models that focus on the transmission dynamics of diseases using fractional order models, as well as comparisons with integer-order models. The findings from this study contribute to the broader understanding of epidemiological modeling, paving the way for more accurate and effective strategies in disease control and prevention.

The spatial-temporal distribution of hepatitis B virus infection in China,2006–2018

ObjectivesHepatitis B is a liver disease caused by Hepatitis B virus (HBV) infection and is highly prevalent in China. To better understand the epidemiological characteristics of hepatitis B in China and develop effective disease control strategies, we employed temporal and spatial statistical methods.MethodsWe obtained HBV incidence data from the Public Health Science Data Center of the Chinese Center for Disease Control and Prevention for the years 2006 to 2018. Using Geographic Information System (GIS) and SaTScan scanning technology, we conducted spatial autocorrelation analysis and spatiotemporal scan analysis to create a map and visualize the distribution of hepatitis B incidence.ResultsWhile hepatitis B incidence rebounded in 2011 and 2017, the overall incidence in China decreased.In the trend analysis by item, the incidence varies from high to low. The global spatial autocorrelation analysis revealed a clustered distribution, and the Moran index analysis of spatial autocorrelation within local regions identified five provinces as H-H clusters (hot spots), while one province was an L-L cluster (cold spot). Spatial scan analysis identified 11 significant spatial clusters.ConclusionsWe found significant clustering in the spatial distribution of hepatitis B incidence and positive spatial correlation of hepatitis B incidence in China. We also identified high-risk times and regional clusters of hepatitis B incidence.

Acyl hydrazone derivatives with trifluoromethylpyridine as potential agrochemical for controlling plant diseases.

Crops are consistently under siege by a multitude of pathogens. These pathogenic microorganisms, including viruses and bacteria, result in substantial reductions in quality and yield globally by inducing detrimental crop diseases, thus posing a significant challenge to global food security. However, the biological activity sepectrumof commercially available pesticides is limitedand the pesticide efficacy is poor, necessitating the urgent development of broad-spectrum and efficient strategies for crop disease prevention and control. The bioassay results revealed that certain target compounds demonstrated outstanding in vivo antiviral efficacy against cucumber mosaic virus and tobacco mosaic virus. In particular, compound D6 showed remarkable antiviral activity against CMV, significantly higher than that of the control agent ningnanmycin. Mechanism of action studies have shown that compound D6 could enhance the activity of defense enzymes and upregulate the expression of genes related to disease resistance, thereby enhancing the antiviral effects in plants. In addition, these compounds displayed superior inhibitory activity against plant bacterial diseases. For Xoo, compound D10 showed an excellent inhibitory effect that was better than that of the control agent bismerthiazol. Scanning electron microscopy and fluorescence double-staining experiments revealed that compound D10 effectively inhibited bacterial growth by disrupting the cell membrane. A series of trifluoromethyl hydrazone derivatives were designed and synthesized, and it was found that they have control effects on plant viruses and bacterial diseases. In addition, this study revealed the mechanism of action of the active compounds and demonstrated their potential as multifunctional crop protectants. © 2024 Society of Chemical Industry.

Modeling on cost-effectiveness of monkeypox disease control strategies with consideration of environmental transmission effects in the presence of vaccination

Modeling on cost-effectiveness of monkeypox disease control strategies with consideration of environmental transmission effects in the presence of vaccination