Analysis of avian disease transmission risk and prevention measures in China

Many zoonotic diseases are found in wild animals and present a serious risk to human health, in particularly the virus carried by birds flying freely around the world is hard to control. There are three main bird migration routes which cover the most areas of China. It is important to investigate and fully understand the types of avian transmitted diseases in key areas on the bird migration routines and its impacts on both birds and human health. However, no literature is available in how about the risk of virus carried by migrating birds, and how to predict and reduce this risk of virus spreading to human being so far. In this paper, we first reviewed the main pathogen types carried by birds, including coronaviruses, influenza viruses, parasites, Newcastle disease virus (NDV), etc., and then discussed the spread risk of avian viruses to human being and animals in key areas of biosafety prevention. We also analyzed and discussed the risk of cross-spread of diseases among different bird species in nature reserves located on bird migration routes which provide sufficient food sources for migratory birds and attract numerous birds. Diseases transmitted by wild birds pose a serious threat to poultry farms, where high density of poultry may become avian influenza virus (AIV) reservoirs, cause a risk of avian influenza outbreaks. Airports are mostly built in suburban areas or remote areas with good ecological environment. There are important transit places for bird migration and densely populated areas, which have serious risk of disease transmission. Finally, this paper puts forward the following prevention suggestions from three aspects. First, establish and improve the monitoring and prediction mechanism of migratory birds, and use laser technology to prevent contact between wild birds and poultry. Second, examine and identify virus types carried by birds in their habitats and carry out vaccination. Third, protect the ecological environment of bird habitat, and keep wild birds in their natural habitat, so as to reduce the contact between wild birds and human and poultry, and thus reduce the risk of virus transmission.

Animal diseases - current developments

The health of domesticated animals and wild animals is frequently threatened by animal illnesses. It typically receives less attention and information than illnesses that also impact humans, including the Corona virus. To be able to respond quickly, it is crucial to understand the epidemic's progression and transmission vectors. Numerous new diseases have been reported in the news over the past 20 years, the majority of which having an animal source (zoonoses). Examples from recent times include the West Nile virus, SARS, avian influenza, and monkeypox. Some developing diseases impact both humans and animals, whereas others only affect either animals or humans. All of these emerging or reemerging illnesses, however, have societal repercussions that are frequently connected to regional and global economy. Understanding the effects of newly emerging animal diseases is crucial, as is promoting closer veterinarian and medical professional collaboration, particularly in rural regions. The index cases for newly developing diseases may be illnesses that affect agricultural laborers.

Does Avian Coronavirus Co-Circulate with Avian Paramyxovirus and Avian Influenza Virus in Wild Ducks in Siberia?

Avian coronaviruses (ACoV) have been shown to be highly prevalent in wild bird populations. More work on avian coronavirus detection and diversity estimation is needed for the breeding territories of migrating birds, where the high diversity and high prevalence of Orthomyxoviridae and Paramyxoviridae have already been shown in wild birds. In order to detect ACoV RNA, we conducted PCR diagnostics of cloacal swab samples from birds, which we monitored during avian influenza A virus surveillance activities. Samples from two distant Asian regions of Russia (Sakhalin region and Novosibirsk region) were tested. Amplified fragments of the RNA-dependent RNA-polymerase (RdRp) of positive samples were partially sequenced to determine the species of Coronaviridae represented. The study revealed a high presence of ACoV among wild birds in Russia. Moreover, there was a high presence of birds co-infected with avian coronavirus, avian influenza virus, and avian paramyxovirus. We found one case of triple co-infection in a Northern Pintail (Anas acuta). Phylogenetic analysis revealed the circulation of a Gammacoronavirus species. A Deltacoronavirus species was not detected, which supports the data regarding the low prevalence of deltacoronaviruses among surveyed bird species.

Strategic construction of mRNA vaccine derived from conserved and experimentally validated epitopes of avian influenza type A virus: a reverse vaccinology approach.

Purpose: The development of vaccines that confer protection against multiple avian influenza A (AIA) virus strains is necessary to prevent the emergence of highly infectious strains that may result in more severe outbreaks. Thus, this study applied reverse vaccinology approach in strategically constructing messenger RNA (mRNA) vaccine construct against avian influenza A (mVAIA) to induce cross-protection while targeting diverse AIA virulence factors. Materials and Methods: Immunoinformatics tools and databases were utilized to identify conserved experimentally validated AIA epitopes. CD8+ epitopes were docked with dominant chicken major histocompatibility complexes (MHCs) to evaluate complex formation. Conserved epitopes were adjoined in the optimized mVAIA sequence for efficient expression in Gallus gallus. Signal sequence for targeted secretory expression was included. Physicochemical properties, antigenicity, toxicity, and potential cross-reactivity were assessed. The tertiary structure of its protein sequence was modeled and validated in silico to investigate the accessibility of adjoined B-cell epitope. Potential immune responses were also simulated in C-ImmSim. Results: Eighteen experimentally validated epitopes were found conserved (Shannon index <2.0) in the study. These include one B-cell (SLLTEVETPIRNEWGCR) and 17 CD8+ epitopes, adjoined in a single mRNA construct. The CD8+ epitopes docked favorably with MHC peptide-binding groove, which were further supported by the acceptable ΔGbind (-28.45 to -40.59 kJ/mol) and Kd (<1.00) values. The incorporated Sec/SPI (secretory/signal peptidase I) cleavage site was also recognized with a high probability (0.964814). Adjoined B-cell epitope was found within the disordered and accessible regions of the vaccine. Immune simulation results projected cytokine production, lymphocyte activation, and memory cell generation after the 1st dose of mVAIA. Conclusion: Results suggest that mVAIA possesses stability, safety, and immunogenicity. In vitro and in vivo confirmation in subsequent studies are anticipated.

Outbreaks of different viral etiologies amidst COVID-19 pandemic

The COVID-19 pandemic has severely affected public health system and surveillance of other communicable diseases across the globe. The lockdown, travel constraints and COVID phobia turned down the number of people with illness visiting to the clinics or hospitals. Besides this, the heavy workload of SARS-CoV-2 diagnosis has led to the reduction in differential diagnosis of other diseases. Consequently, it added to the underlying burden of many diseases which remained under-diagnosed. Amidst the pandemic, the rise of emerging and re-emerging infectious diseases was observed worldwide and reported to the World Health Organization i.e., Crimean Congo Hemorrhagic Fever (2022, Iraq;2021 India), Nipah virus (2021, India), Zika virus (2021, India), and H5N1 influenza (2021, India), Monkeypox (2022, multicountry outbreak), Ebola virus disease (2022, DRC, Uganda;2021, DRC, Guinea;2020, DRC), Marburg (2022, Ghana;2021, Guinea), Yellow fever (2022, Uganda, Kenya, West and Central Africa;2021, Ghana, Venezuela, Nigeria;2020, Senegal, Guinea, Nigeria, Gabon;2020, Ethiopia, Sudan, Uganda), Dengue (2022, Nepal, Pakistan, Sao Tome, Temor-Leste;2021, Pakistan), Middle east respiratory syndrome coronavirus (2022, Oman, Qatar;2021, Saudi Arabia, UAE;2020, Saudi Arabia, UAE), Rift valley fever (2021, Kenya;2020, Mauritania), wild poliovirus type 1 (2022, Mozambique), Lassa fever (2022, Guinea, Togo, Nigeria;2020, Nigeria), Avian Influenza (H3N8) (2022, China), Avian Influenza (H5N1) (2022, USA), H10N3 influenza (2021, China), Hepatitis E virus (2022, Sudan), Measles (2022, Malawi, Afghanistan;2020, Burundi, Mexico), Mayaro virus disease (2020, French Guiana), Oropouche virus disease (2020, French Guiana). All these diseases were associated with high morbidity and burdened the public health system during the COVID-19 pandemic. During this critical public health menace, majority of the laboratory workforce was mobilized to the SARS-CoV-2 diagnosis. This has limited the surveillance efforts that likely led to under diagnosis and under-detection of many infectious pathogens. Lockdowns and travel limitations also put a hold on human and animal surveillance studies to assess the prevalence of these zoonotic viruses. In addition, lack of supplies and laboratory personnel and an overburdened workforce negatively impacted differential diagnosis of the diseases. This is especially critical given the common symptoms between COVID-19 and other pathogens causing respiratory illnesses. Additionally, the vaccination programs against various vaccine preventable diseases were also hampered which might have added to the disease burden. Despite these challenges, the world is better prepared to detect and respond to emerging/re-emerging pathogens. India now has more than 3000 COVID-19 diagnostic laboratories and an enhanced hospital infrastructure. In addition, mobile BSL-3 facilities are being validated for onsite sampling and testing in remote areas during outbreak situations and surveillance activities. This will undoubtedly be valuable as the COVID-19 pandemic evolves as well as during future outbreaks and epidemics. In conclusion, an increase in the emergence and re-emergence of viruses demonstrates that other infectious diseases have been neglected during the COVID-19 pandemic. Lessons learned from the infrastructure strengthening, collaborations with multiple stakeholders, increased laboratory and manufacturing capacity, large-scale COVID-19 surveillance, extensive network for laboratory diagnosis, and intervention strategies can be implemented to provide quick, concerted responses against the future threats associated with other zoonotic pathogens.

REMDESIVIR RETAINS POTENT ACTIVITY AGAINST SARS-CoV-2 VARIANTS OF CONCERN

Background: Recent SARS-CoV-2 variants of concern (VOCs) have shown a progressive loss of sensitivity to monoclonal antibody therapeutics. Remdesivir (RDV) is a nucleotide analog prodrug that targets the viral RNA-dependent RNA polymerase (RdRp) Nsp12 and is approved to treat COVID-19 in hospitalized and non-hospitalized patients. Nsp12 is highly conserved across VOCs to date and RDV antiviral activity against previous VOCs (Alpha to Omicron BA.1) has been maintained. Here, we conduct a structural analysis of Nsp12 substitutions observed in recent Omicron subvariants (BA.2, BA.2.12.1, BA.4, BA.5 and BA.2.75) and assess RDV antiviral activity against clinical isolates and sitedirected mutants (SDMs) in a replicon system. Method(s): The prevalence of Nsp12 substitutions in Omicron subvariants was evaluated by analysis of sequences from the Global Initiative on Sharing Avian Influenza Data (GISAID) EpiCoV database. Structural analysis of identified substitutions was conducted on a prior cryo-electron microscopy-based model of the replication-transcription complex. Antiviral activity against subvariant clinical isolates was assessed by nucleoprotein ELISA in A549-hACE2-TMPRSS2 cells and by SDMs in the replicon system. Result(s): Genomic analysis of >1.4 million Omicron subvariant sequences revealed unique substitutions in Nsp12 compared to the ancestral WA1 strain. Besides P323L, present in all subvariants, G671S was observed in 95.9% of BA.2.75 sequences, F694Y was observed in <=1.9% of BA.4, BA.5 and BA.2.75 sequences, and Y521C was observed in 1.7% of BA.5 sequences. As anticipated, structural analysis of these substitutions showed no direct interaction with the incoming RDV nucleotide triphosphate or the viral RNA. Phenotyping of clinical isolates of Omicron subvariants BA.2, BA.2.12.1, BA.4, BA.5, and BA.2.75 consistently resulted in mean RDV EC50 values of 24.5 nM (BA.2) to 106.0 nM (BA.5). This represented 0.15-to 0.66-fold changes compared to WA1, indicating no loss of in vitro RDV antiviral activity against these VOCs. P323L, G671S, and F694Y were shown previously to have no impact on RDV antiviral activity. Similarly, the individual substitution Y521C showed no change in RDV susceptibility in the SARS-CoV-2 replicon system. Conclusion(s): RDV retained potent in vitro antiviral activity against all tested Omicron VOCs with potencies comparable to the WA1 isolate. These data support the continued use of RDV in patients infected with Omicron subvariants.

Infection Management of Virus-Diagnosing Biosensors Based on MXenes: An Overview

The occurrence of sudden viral outbreaks, including (Covid-19, H1N1 flu, H5N1 flu) has globally challenged the existing medical facilities and raised critical concerns about saving affected lives, especially during pandemics. The detection of viral infections at an early stage using biosensors has been proven to be the most effective, economical, and rapid way to combat their outbreak and severity. However, state-of-the-art biosensors possess bottlenecks of long detection time, delayed stage detection, and sophisticated requirements increasing the cost and complexities of biosensing strategies. Recently, using two-dimensional MXenes as a sensing material for architecting biosensors has been touted as game-changing technology in diagnosing viral diseases. The unique surface chemistries with abundant functional terminals, excellent conductivity, tunable electric and optical attributes and high specific surface area have made MXenes an ideal material for architecting virus-diagnosing biosensors. There are numerous detecting modules in MXene-based virus-detecting biosensors based on the principle of detecting various biomolecules like viruses, enzymes, antibodies, proteins, and nucleic acid. This comprehensive review critically summarizes the state-of-the-art MXene-based virus-detecting biosensors, their limitations, potential solutions, and advanced intelligent prospects with the integration of internet-of-things, artificial intelligence, 5G communications, and cloud computing technologies. It will provide a fundamental structure for future research dedicated to intelligent and point-of-care virus detection biosensors.

Textual Research on Key Information of Ancient Classical Prescription Dayuanyin.

Dayuanyin,a representative prescription for the treatment of dampness pathogen lodging in pleurodiaphragmatic interspace syndrome,was first recorded in Treatise on Pestilence(<<>>)by Wu Youke in the Ming Dynasty for dealing with pestilence,and it still plays an important role in the treatment of coronavirus disease 2019(COVID-19)differentiated into dampness stagnating in lung syndrome. The related original ancient records were retrieved from the Chinese Classics of Traditional Chinese Medicine(Version 5.0),Full-text Database of Ancient Chinese Medicine Books,and Ancient Books of Traditional Chinese Medicine Database (http://www. gydc. ac. cn:81/),with 'Dayuanyin' and 'Dayuansan' as the search terms,followed by statistical analysis and textual research. The composition,dosage,processing of original medicinal materials,efficacy, indications, processing and administration methods, modern basic research, and clinical applications of Dayuanyin were summarized,so as to provide literature reference for its modern development and clinical application. The findings demonstrated that the composition in most medical records was identical with that of the original prescription,except that some records concerning Angelicae Dahuricae Radix and Tsaoko Fructus differed. In terms of dosage,it did not change much,with the only difference observed in Tsaoko Fructus. The processing methods of medicinal materials in Dayuanyin were not specified in historical records,so the raw medicinal materials were recommended. The processing and administration methods in the original record were basically followed in the later generations,except that some medical records chose Zingiberis Rhizoma Recens as the guide and changed the decocting amount and administration time. In terms of efficacy and indications, Dayuanyin was originally developed for dispelling pathogenic Qi away from the pleurodiaphragmatic interspace, but later employed for the treatment of such diseases as 'pestilence','epidemic malaria',and 'seasonal epidemic'. It was mainly indicated to 'epidemic diseases' with latent pathogen in pleurodiaphragmatic interspace as the pathogenesis and fever as the manifestation. In modern clinical application,ancients physicians considered 'fever' and 'powder-like tongue coating' as the important signs for this prescription. Modern physicians have utilized Dayuanyin for treating fever,diseases in the digestive,respiratory,urinary,and endocrine systems,skin diseases,pediatric diseases,as well as epidemic diseases like influenza,severe acute respiratory syndrome (SARS),and avian flu due to its good effects.Copyright © 2021, China Academy of Chinese Medical Sciences Institute of Chinese Materia Medica. All rights reserved.

Zoonotic Animal Influenza Virus and Potential Mixing Vessel Hosts.

Influenza viruses belong to the family Orthomyxoviridae with a negative-sense, single-stranded segmented RNA genome. They infect a wide range of animals, including humans. From 1918 to 2009, there were four influenza pandemics, which caused millions of casualties. Frequent spillover of animal influenza viruses to humans with or without intermediate hosts poses a serious zoonotic and pandemic threat. The current SARS-CoV-2 pandemic overshadowed the high risk raised by animal influenza viruses, but highlighted the role of wildlife as a reservoir for pandemic viruses. In this review, we summarize the occurrence of animal influenza virus in humans and describe potential mixing vessel or intermediate hosts for zoonotic influenza viruses. While several animal influenza viruses possess a high zoonotic risk (e.g., avian and swine influenza viruses), others are of low to negligible zoonotic potential (e.g., equine, canine, bat and bovine influenza viruses). Transmission can occur directly from animals, particularly poultry and swine, to humans or through reassortant viruses in "mixing vessel" hosts. To date, there are less than 3000 confirmed human infections with avian-origin viruses and less than 7000 subclinical infections documented. Likewise, only a few hundreds of confirmed human cases caused by swine influenza viruses have been reported. Pigs are the historic mixing vessel host for the generation of zoonotic influenza viruses due to the expression of both avian-type and human-type receptors. Nevertheless, there are a number of hosts which carry both types of receptors and can act as a potential mixing vessel host. High vigilance is warranted to prevent the next pandemic caused by animal influenza viruses.

Current understanding of the airborne transmission of important viral animal pathogens in spreading disease

Current research on airborne transmission of African swine fever virus (ASFV), porcine epidemic diarrhoea virus (PEDV), avian influenza (AIV), porcine reproductive and respiratory syndrome virus (PRRSV), and foot and mouth disease virus (FMDV) was reviewed to evaluate commonalities, knowledge gaps, and methodologies of studying airborne transmission of animal diseases. The reviewed studies were categorised as short-range transmission (within a single facility) and long-range transmission (beyond a single site). Short-range airborne transmission was demonstrated for at least one strain of the above-mentioned pathogens in experimental settings. Most studies reported in the literature concern FMDV, with limited information for ASFV and PEDV, particularly for short-range airborne transmission. Air sampling upwind, downwind, and within infected facilities has been commonly used to demonstrate long-range airborne transmission. The amount of evidence from air sampling for each of the reviewed viruses varies from no evidence on ASFV to evidence from multiple settings for AIV. Computer modelling has been used to study past outbreaks of infectious diseases to assess the contribution of airborne transmission with a multitude of computer models reported in the literature for simulating long-range airborne transmission of FMDV based on past outbreaks. This has resulted in predictive tools for assessing future risk of airborne transmission. Some important computer models are based on epidemiology analysis, weather analysis, and air dispersion. Few models are reported for ASFV, PEDV, and PRRSV. Studies in the literature indicate that airborne transmission is generally affected by virus strain, aerosol type, shedding duration and concentration, environmental conditions, and infectious dose.

Emergence of BA.4/BA.5 Omicron Sub-lineages and Increased SARS-CoV-2 Incidence in Senegal

Background: The Omicron variant B.1.1.529 has led to a new dynamic in the COVID-19 pan-demic, with an increase in cases worldwide. Its rapid propagation favors the emergence of novel sub-lineages, including BA.4 and BA.5. The latter has shown increased transmissibility compared to other Omicron sub-lineages. In Senegal, the emergence of the Omicron variant in December 2021 characterized the triggering of a short and dense epidemiological wave that peaked at the end of February. This wave was followed by a period with a significant drop in the number of COVID-19 cases, but an upsurge in SARS-CoV-2 infection has been noted since mid-June. Objective(s): The purpose of this brief report is to give an update regarding the genomic situation of SARS-CoV-2 in Dakar during this phase of recrudescence of cases. Method(s): We performed amplicon-based SARS-CoV-2 sequencing on nasopharyngeal swab samples from declared COVID-19 patients and outbound travelers that tested positive. Result(s): Ongoing genomic surveillance activities showed that more than half of recent COVID-19 cases were due to the BA.4 and BA.5 sub-lineages that share two critical mutations associated with increased transmissibility and immune response escape. The circulation of recombinants between Omicron sub-lineages was also noted. Conclusion(s): Despite the lack of proven severity of BA.4 and BA.5 sub-lineages, their increased transmis-sibility causes a rapid spread of the virus, hence a surge in the number of cases. This rapid spread consti-tutes a greater risk of exposure for vulnerable patients. To tackle this issue, any increase in the number of cases must be monitored to support public health stakeholders. Therefore, genomic surveillance is an ever-essential element in managing this pandemic.Copyright © 2022 Bentham Science Publishers.

Textual Research on Key Information of Ancient Classical Prescription Dayuanyin.

Dayuanyin,a representative prescription for the treatment of dampness pathogen lodging in pleurodiaphragmatic interspace syndrome,was first recorded in Treatise on Pestilence(<<>>)by Wu Youke in the Ming Dynasty for dealing with pestilence,and it still plays an important role in the treatment of coronavirus disease 2019(COVID-19)differentiated into dampness stagnating in lung syndrome. The related original ancient records were retrieved from the Chinese Classics of Traditional Chinese Medicine(Version 5.0),Full-text Database of Ancient Chinese Medicine Books,and Ancient Books of Traditional Chinese Medicine Database (http://www. gydc. ac. cn:81/),with 'Dayuanyin' and 'Dayuansan' as the search terms,followed by statistical analysis and textual research. The composition,dosage,processing of original medicinal materials,efficacy, indications, processing and administration methods, modern basic research, and clinical applications of Dayuanyin were summarized,so as to provide literature reference for its modern development and clinical application. The findings demonstrated that the composition in most medical records was identical with that of the original prescription,except that some records concerning Angelicae Dahuricae Radix and Tsaoko Fructus differed. In terms of dosage,it did not change much,with the only difference observed in Tsaoko Fructus. The processing methods of medicinal materials in Dayuanyin were not specified in historical records,so the raw medicinal materials were recommended. The processing and administration methods in the original record were basically followed in the later generations,except that some medical records chose Zingiberis Rhizoma Recens as the guide and changed the decocting amount and administration time. In terms of efficacy and indications, Dayuanyin was originally developed for dispelling pathogenic Qi away from the pleurodiaphragmatic interspace, but later employed for the treatment of such diseases as 'pestilence','epidemic malaria',and 'seasonal epidemic'. It was mainly indicated to 'epidemic diseases' with latent pathogen in pleurodiaphragmatic interspace as the pathogenesis and fever as the manifestation. In modern clinical application,ancients physicians considered 'fever' and 'powder-like tongue coating' as the important signs for this prescription. Modern physicians have utilized Dayuanyin for treating fever,diseases in the digestive,respiratory,urinary,and endocrine systems,skin diseases,pediatric diseases,as well as epidemic diseases like influenza,severe acute respiratory syndrome (SARS),and avian flu due to its good effects.Copyright © 2021, China Academy of Chinese Medical Sciences Institute of Chinese Materia Medica. All rights reserved.

Viral diseases of poultry in Assam, India: a review

The Indian poultry market is estimated to have an annual growth rate of 8.1% as of today. However, infectious diseases in poultry pose an important constraint in the growth and development of this sector in our region. Among infectious diseases, viral diseases of poultry pose a serious threat to the poultry industry from an economic point of view. Several viral disease outbreaks have been reported by various researchers from different parts of the country. Among the common viral diseases of poultry, incidences of Newcastle disease, Avian Influenza, Fowl Pox, Infectious Bursal Disease, Marek's disease, Infectious Bronchitis, Infectious Laryngotracheitis and Inclusion Body Hepatitis are significant in Assam as well as other parts of India. Thorough epidemiological studies followed by the identification of different serotypes, pathotypes, strains, etc. by genotyping and molecular characterization of viral disease pathogens may lead to ways to control and eradicate the diseases. Importance should be given to maintaining basic preventive measures like biosecurity, farm hygiene, and proper vaccination. In a developing country like India, disease outbreaks can impact the country's economy. In this study, a brief view of the common viral disease of poultry and its diagnosis and control strategies in Assam, India is depicted. However, this review well indicates a plethora of avian diseases that have occurred over the years causing a severe impact on poultry farming as a whole.

Rate of Multiple Viral and Bacterial CoInfection(s) in Influenza A/H9N2-Infected Broiler Flocks.

Repeated cases of low pathogenic influenza A/H9N2 virus (IAV/H9N2) have been reported in commercial chickens since its emergence in 1998 in Pakistan. However, recently increased mortality and severe respiratory complications under field conditions have been noticed, suggesting concomitant influenza infections with respiratory viral and/or bacterial pathogens. Therefore, the present study aimed to investigate the presence of IAV/H9N2 coinfecting with multiple viral and bacterial pathogens in broiler chicken flocks. We surveyed 60 broiler flocks with respiratory signs from March through July 2019 in Punjab, Pakistan. Suspected flocks were screened for the presence of IAV using a lateral-flow device. Tracheal, cloacal, and bone marrow samples were collected and further tested for seven viral agents (chicken anemia; Newcastle disease; infectious bronchitis; infectious laryngeotracheitis [ILT]; and IAV subtypes H9, H7, and H5) and three bacterial agents (Mycoplasma gallisepticum; Mycoplasma synovae; Ornithobacterium rhinotracheale [ORT]) using PCR assays. Upon initial screening for IAV, 35/60 (58.3%) flocks tested positive. The coinfection of IAV/H9N2 with other pathogens was detected in 25 (71.4%) flocks and only IAV/H9N2 was detected in 10 (28.6%) flocks out of total positive IAV flocks (n = 35). IAV subtypes H5 and H7, ILT, and ORT were not detected throughout the study period. The detection rate of double, triple, and quadruple combinations of coinfections with IAV/H9N2 were 37% (13 flocks), 26% (9 flocks), 9% (3 flocks), respectively. Higher average mortality (28.5%) was found in broiler chicken flocks coinfected with viral and/or bacterial pathogens than in flocks where only H9 low pathogenic IAV/H9N2 was detected (20.8%). In conclusion, higher circulation of IAV/H9N2 with other viral and bacterial pathogens may contribute to higher production and economic losses at the farm level.

Nota de investigación- Tasa de coinfecciones virales y bacterianas múltiples en parvadas de pollos de engorde infectadas con virus influenza A/H9N2. Se han reportado varios casos del virus de influenza A de baja patogenicidad H9N2 (IAV/H9N2) en pollos comerciales desde su aparición en 1998 en Pakistán. Sin embargo, recientemente se ha observado un aumento de la mortalidad y complicaciones respiratorias graves en condiciones de campo, lo que sugiere infecciones concomitantes de influenza con patógenos respiratorios virales y/o bacterianos. Por lo tanto, el presente estudio tuvo como objetivo investigar la presencia del virus de influenza aviar H9N2 coinfectando con múltiples patógenos virales y bacterianos en parvadas de pollos de engorde. Se evaluaron 60 parvadas de pollos de engorde con signos respiratorios desde marzo hasta julio del año 2019 en Punjab, Pakistán. Las parvadas sospechosas fueron analizadas para detectar la presencia del virus de influenza aviar utilizando un dispositivo de flujo lateral. Se recolectaron muestras traqueales, cloacales y de médula ósea y se analizaron para detectar siete agentes virales (anemia infecciosa aviar, enfermedad de Newcastle, bronquitis infecciosa, laringeotraqueítis infecciosa [ILT] y subtipos H9, H7 y H5 de influenza aviar) y tres agentes bacterianos (Mycoplasma gallisepticum ; Mycoplasma sinovae; Ornithobacterium rhinotracheale [ORT]) utilizando ensayos de PCR. Tras la detección inicial del virus de la influenza aviar, 35/60 (58.3 %) parvadas resultaron positivas. La coinfección del virus de la influenza H9N2 con otros patógenos se detectó en 25 (71.4 %) parvadas y el virus de influenza aviar H9N2 fue detectado solo en 10 (28.6 %) parvadas del total de parvadas positivas (n = 35). Los subtipos H5 y H7 del virus de influenza, ILT y ORT no se detectaron durante el período de estudio. La tasa de detección de combinaciones dobles, triples y cuádruples de coinfecciones con el virus de influenza H9N2 fue del 37 % (13 parvadas), del 26% (9 parvadas), del 9 % (3 parvadas), respectivamente. Se encontró una mortalidad promedio más alta (28.5 %) en lotes de pollos de engorde coinfectados con patógenos virales y/o bacterianos que en lotes donde solo se detectó al virus de influenza H9 de baja patogenicidad (20.8%). En conclusión, una mayor circulación del virus de influenza aviar H9N2 con otros patógenos virales y bacterianos puede contribuir a mayores pérdidas en la producción y económicas a nivel de granja.

Gain-of-function research.

The term Gain-of-Function (GoF) describes the gain of new functions by organisms through genetic changes, which can naturally occur or by experimental genetic modifications. Gain-of-Function research on viruses is enhancing transmissibility, virus replication, virulence, host range, immune evasion or drug and vaccine resistance to get insights into the viral mechanisms, to create and analyze animal models, to accelerate drug and vaccine development and to improve pandemic preparedness. A subset is the GoF research of concern (GOFROC) on enhanced potentially pandemic pathogens (ePPPs) that could be harmful for humans. A related issue is the military use of research as dual-use research of concern (DURC). Influenza and coronaviruses are main research targets, because they cause pandemics by airborne infections. Two studies on avian influenza viruses initiated a global debate and a temporary GoF pause in the United States which ended with a new regulatory framework in 2017. In the European Union and China, GoF and DURC are mainly covered by the legislation for laboratory safety and genetically modified organisms. After the coronavirus outbreaks, the GoF research made significant advances, including analyses of modified MERS-like and SARS-like viruses and the creation of synthetic SARS-CoV-2 viruses as a platform to generate mutations. The GoF research on viruses will still play an important role in future, but the need to clarify the differences and overlaps between GoF research, GOFROC and DURC and the need for specialized oversight authorities are still debated.

The Rise of Heatstroke as a Method of Depopulating Pigs and Poultry: Implications for the US Veterinary Profession.

Depopulation of food-producing animals is becoming increasingly common in response to both disease outbreaks and supply chain disruptions. In 2019, the American Veterinary Medical Association released depopulation guidelines classifying certain heatstroke-based killing methods as "permitted in constrained circumstances", when circumstances of the emergency constrain reasonable implementation of "preferred" methods. Since then, tens of millions of birds and pigs have been killed by such methods, termed ventilation shutdown (VSD) Plus Heat and VSD Plus High Temperature and Humidity. While no research using validated measures of animal welfare assessment has been performed on these methods, their pathophysiology suggests that animals are likely to experience pain, anxiety, nausea, and heat distress prior to loss of consciousness. Heatstroke-based methods may result in prolonged suffering and often do not achieve 100% mortality. Potential and available alternative depopulation methods are briefly reviewed. The veterinary profession's ethical obligation to protect animal welfare in the context of depopulations is discussed.

An Evaluation of Avian Influenza Virus Whole-Genome Sequencing Approaches Using Nanopore Technology.

As exemplified by the global response to the SARS-CoV-2 pandemic, whole-genome sequencing played an important role in monitoring the evolution of novel viral variants and provided guidance on potential antiviral treatments. The recent rapid and extensive introduction and spread of highly pathogenic avian influenza virus in Europe, North America, and elsewhere raises the need for similarly rapid sequencing to aid in appropriate response and mitigation activities. To facilitate this objective, we investigate a next-generation sequencing platform that uses a portable nanopore sequencing device to generate and present data in real time. This platform offers the potential to extend in-house sequencing capacities to laboratories that may otherwise lack resources to adopt sequencing technologies requiring large benchtop instruments. We evaluate this platform for routine use in a diagnostic laboratory. In this study, we evaluate different primer sets for the whole genome amplification of influenza A virus and evaluate five different library preparation approaches for sequencing on the nanopore platform using the MinION flow cell. A limited amplification procedure and a rapid procedure are found to be best among the approaches taken.

Influx of Backyard Farming with Limited Biosecurity Due to the COVID-19 Pandemic Carries an Increased Risk of Zoonotic Spillover in Cambodia.

Backyard farming with limited biosecurity creates a massive potential for zoonotic spillover. Cambodia, a developing nation in Southeast Asia, is a hub for emerging and endemic infectious diseases. Due to pandemic-induced job losses in the tourism sector, rumors suggest that many former Cambodian tour guides have turned to backyard farming as a source of income and food security. A cross-sectional study including 331 tour guides and 69 poultry farmers in Cambodia before and during the novel coronavirus disease 2019 (COVID-19) pandemic was conducted. Participants were administered a survey to assess food security, income, and general farming practices. Survey data were collected to evaluate the risk perceptions for avian influenza virus (AIV), antimicrobial resistance (AMR), and general biosecurity management implemented on these poultry farms. Overall, food security decreased for 80.1% of the tour guides during the COVID-19 pandemic. Approximately 21% of the tour guides interviewed used backyard poultry farming to supplement losses of income and food insecurity during the COVID-19 pandemic, with a significantly higher risk than for traditional poultry farmers. Agricultural intensification in Cambodia due to the COVID-19 pandemic has caused an influx of makeshift farms with limited biosecurity. Inadequate biosecurity measures in animal farms can facilitate spillover and contribute to future pandemics. Improved biosecurity and robust viral surveillance systems are critical for reducing the risk of spillover from backyard farms. IMPORTANCE While this study highlights COVID-19-associated changes in poultry production at a small scale in Cambodia, poultry production is expected to expand due to an increase in the global demand for poultry protein during the pandemic, changes in urbanization, and the reduction of the global pork supply caused by African swine fever (ASF). The global demand and surge in poultry products, combined with inadequate biosecurity methods, can lead to an increased risk of domestic animal and human spillovers of zoonotic pathogens such as avian influenza. Countries in regions of endemicity are often plagued by complex emergency situations (i.e., food insecurity and economic fallouts) that hinder efforts to effectively address the emergence (or reemergence) of zoonotic diseases. Thus, novel surveillance strategies for endemic and emerging infectious diseases require robust surveillance systems and biosecurity training programs to prevent future global pandemics.