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1.
Viruses ; 15(3)2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36992498

RESUMO

A One Health cross-sectoral surveillance approach was implemented to screen biological samples from bats, pigs, and humans at high-risk interfaces for zoonotic viral spillover for five viral families with zoonotic potential in Viet Nam. Over 1600 animal and human samples from bat guano harvesting sites, natural bat roosts, and pig farming operations were tested for coronaviruses (CoVs), paramyxoviruses, influenza viruses, filoviruses and flaviviruses using consensus PCR assays. Human samples were also tested using immunoassays to detect antibodies against eight virus groups. Significant viral diversity, including CoVs closely related to ancestors of pig pathogens, was detected in bats roosting at the human-animal interfaces, illustrating the high risk for CoV spillover from bats to pigs in Viet Nam, where pig density is very high. Season and reproductive period were significantly associated with the detection of bat CoVs, with site-specific effects. Phylogeographic analysis indicated localized viral transmission among pig farms. Our limited human sampling did not detect any known zoonotic bat viruses in human communities living close to the bat cave and harvesting bat guano, but our serological assays showed possible previous exposure to Marburg virus-like (Filoviridae), Crimean-Congo hemorrhagic fever virus-like (Bunyaviridae) viruses and flaviviruses. Targeted and coordinated One Health surveillance helped uncover this viral pathogen emergence hotspot.


Assuntos
Quirópteros , Infecções por Coronavirus , Coronavirus , Filoviridae , Saúde Única , Humanos , Animais , Suínos , Vietnã/epidemiologia , Filogenia , Zoonoses
2.
Sci Total Environ ; 863: 160748, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36513230

RESUMO

Wildlife and wildlife interfaces with people and livestock are essential surveillance targets to monitor emergent or endemic pathogens or new threats affecting wildlife, livestock, and human health. However, limitations of previous investments in scope and duration have resulted in a neglect of wildlife health surveillance (WHS) systems at national and global scales, particularly in lower and middle income countries (LMICs). Building on decades of wildlife health activities in LMICs, we demonstrate the implementation of a locally-driven multi-pronged One Health approach to establishing WHS in Cambodia, Lao PDR and Viet Nam under the WildHealthNet initiative. WildHealthNet utilizes existing local capacity in the animal, public health, and environmental sectors for event based or targeted surveillance and disease detection. To scale up surveillance systems to the national level, WildHealthNet relies on iterative field implementation and policy development, capacity bridging, improving data collection and management systems, and implementing context specific responses to wildlife health intelligence. National WHS systems piloted in Cambodia, Lao PDR, and Viet Nam engaged protected area rangers, wildlife rescue centers, community members, and livestock and human health sector staff and laboratories. Surveillance activities detected outbreaks of H5N1 highly pathogenic avian influenza in wild birds, African swine fever in wild boar (Sus scrofa), Lumpy skin disease in banteng (Bos javanicus), and other endemic zoonotic pathogens identified as surveillance priorities by local stakeholders. In Cambodia and Lao PDR, national plans for wildlife disease surveillance are being signed into legislation. Cross-sectoral and trans-disciplinary approaches are needed to implement effective WHS systems. Long-term commitment, and paralleled implementation and policy development are key to sustainable WHS networks. WildHealthNet offers a roadmap to aid in the development of locally-relevant and locally-led WHS systems that support the global objectives of the World Organization for Animal Health's Wildlife Health Framework and other international agendas.


Assuntos
Febre Suína Africana , Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Humanos , Animais , Bovinos , Suínos , Animais Selvagens , Sudeste Asiático/epidemiologia
3.
Appl Opt ; 61(10): 2518-2524, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35471317

RESUMO

This study presents a comprehensive method for designing a multifocal contact lens (MCL) with Snell's law and non-uniform rational B-spline (NURBS) curves. Instead of using thin lens approximation, general mathematical formulas have been developed to achieve the accurate coordinates of points on the anterior lens surface profile of the MCL to meet various given optical power distributions. Then the NURBS curve is adjusted to fit these data points to obtain the smooth front lens surface profile. This method not only improves the accuracy of the optical power profiles of MCLs but also reduces the spherical aberration in near/distance optical zones. The experimental results show that the power profiles of soft MCLs agree with those of the simulation results and original design requirements. The proposed method has been proven for the MCL design, and it can be feasibly applied in complex optical lens designs.

4.
Front Public Health ; 10: 826116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356028

RESUMO

Despite the discovery of several closely related viruses in bats, the direct evolutionary progenitor of SARS-CoV-2 has not yet been identified. In this study, we investigated potential animal sources of SARS-related coronaviruses using archived specimens from Sunda pangolins (Manis javanica) and Chinese pangolins (Manis pentadactyla) confiscated from the illegal wildlife trade, and from common palm civets (Paradoxurus hermaphroditus) raised on wildlife farms in Viet Nam. A total of 696 pangolin and civet specimens were screened for the presence of viral RNA from five zoonotic viral families and from Sarbecoviruses using primers specifically designed for pangolin coronaviruses. We also performed a curated data collection of media reports of wildlife confiscation events involving pangolins in Viet Nam between January 2016 and December 2020, to illustrate the global pangolin supply chain in the context of Viet Nam where the trade confiscated pangolins were sampled for this study. All specimens from pangolins and civets sampled along the wildlife supply chains between February 2017 and July 2018, in Viet Nam and tested with conventional PCR assays designed to detect flavivirus, paramyxovirus, filovirus, coronavirus, and orthomyxovirus RNA were negative. Civet samples were also negative for Sarbecoviruses, but 12 specimens from seven live pangolins confiscated in Hung Yen province, northern Viet Nam, in 2018 were positive for Sarbecoviruses. Our phylogenetic trees based on two fragments of the RdRp gene revealed that the Sarbecoviruses identified in these pangolins were closely related to pangolin coronaviruses detected in pangolins confiscated from the illegal wildlife trade in Yunnan and Guangxi provinces, China. Our curated data collection of media reports of wildlife confiscation events involving pangolins in Viet Nam between January 2016 and December 2020, reflected what is known about pangolin trafficking globally. Pangolins confiscated in Viet Nam were largely in transit, moving toward downstream consumers in China. Confiscations included pangolin scales sourced originally from Africa (and African species of pangolins), or pangolin carcasses and live pangolins native to Southeast Asia (predominately the Sunda pangolin) sourced from neighboring range countries and moving through Viet Nam toward provinces bordering China.


Assuntos
COVID-19 , Pangolins , Animais , Animais Selvagens , China , Humanos , Filogenia , SARS-CoV-2 , Vietnã/epidemiologia
5.
Glob Health Sci Pract ; 10(6)2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36951282

RESUMO

As part of a public health behavior change and communication strategy related to the identification of a novel ebolavirus in bats in Sierra Leone in 2016, a consortium of experts launched an effort to create a widely accessible resource for community awareness and education on reducing disease risk. The resulting picture book, Living Safely With Bats, includes technical content developed by a consortium of experts in public health, animal health, conservation, bats, and disease ecology from 30 countries. The book has now been adapted, translated, and used in more than 20 countries in Africa and Asia. We review the processes used to integrate feedback from local stakeholders and multidisciplinary experts. We also provide recommendations for One Health and other practitioners who choose to pursue the development and evaluation of this or similar zoonotic disease risk mitigation tools.


Assuntos
Quirópteros , Ebolavirus , Saúde Única , Animais , Humanos , Serra Leoa , África
6.
Klin Monbl Augenheilkd ; 238(3): 282-287, 2021 Mar.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-32659842

RESUMO

BACKGROUND: Symptoms due to dry eye in the form of keratoconjunctivitis sicca (KCS) are often seen after cataract surgery. We investigated the influence of cataract surgery on tear film stability on the ocular surface. MATERIAL AND METHODS: 60 eyes of 60 patients who underwent cataract surgery were included in a prospective study in 2017 at the Eye Hospital in Hanoi (Vietnam National Institute of Ophthalmology). The mean age of the patients was 65 ± 10 years. The phacoemulsification was performed under topical anaesthesia by a clear corneal incision and implantation of a foldable IOL. The parameters for the evaluation of the change of the tear film included subjective patient data using the Ocular Surface Disease Index questionnaire (OSDI), findings of the Schirmer I test, the tear break-up time (TBUT) as well as the tear meniscus height (TMH) measured noninvasively with the Keratograph 5M (Oculus). In addition, conjunctival and corneal changes were examined after vital staining with fluorescein for the cornea and rose bengal for the conjunctiva. Data were collected preoperatively, at 1 week, 1 month and 3 months postoperatively. According to DEWS, the disease is classified into 4 groups: mild, moderate, severe and very severe. RESULTS: One week after surgery, the total score according to OSDI was significantly increased with a total value of 14.4 ± 4.2 (p = 0.001). Schirmer I was 15.8 ± 4.3 mm preoperatively and decreased significantly in the first postoperative week (p = 0.001), before reaching the preoperative level again after three months. TBUT was 12.6 ± 1.5 s preoperatively, decreased significantly to 9.7 ± 1.5 s during the first postoperative week, and normalized to 12.4 ± 1.3 s by the end of the third month. The meniscus height was 0.245 ± 0.055 mm preoperatively, significantly lowered to 0.229 ± 0.057 mm in the first postoperative period and nearly normalised by the third postoperative month to 0.241 ± 0.051 mm. In the first postoperative week, the rate of mild KCS was observed in 30% of patients. At one month, this decreased to 10% and at three months was no longer demonstrable in any patient. CONCLUSION: One of three patients experienced mild KCS after cataract surgery. The symptoms lasted up to three months. This should be taken into account preoperatively and appropriate therapy should be planned.


Assuntos
Extração de Catarata , Catarata , Síndromes do Olho Seco , Oftalmologia , Idoso , Córnea/cirurgia , Síndromes do Olho Seco/diagnóstico , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Lágrimas
7.
Transbound Emerg Dis ; 68(5): 2669-2675, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33351995

RESUMO

African Swine Fever (ASF) is a highly contagious and fatal viral disease affecting both domestic and wild suids. The virus was introduced to Southeast Asia in early 2019 and has since spread rapidly throughout the region. Although significant efforts have been made to track and diagnose the disease in domestic pigs, very little is known about ASF in free-ranging wild boar and their potential role in maintaining the disease within Southeast Asia. Through a collaboration between government and non-government actors in Laos, Viet Nam, and Cambodia, investigations were conducted to (a) characterize the interface between domestic pigs and wild boar, (b) document risk factors for likely ASF spillover into wild boar populations by way of this interface, and (c) determine whether ASF in wild boar could be detected in each country. An extensive overlap between wild boar habitat and domestic pig ranging areas was found around villages bordering forests in all three countries, creating a high-risk interface for viral spillover between domestic pig and wild boar populations. Fifteen and three wild boar carcasses were detected through passive reporting in Laos and Viet Nam, respectively, in 2019 and early 2020. Four of five carcasses screened in Laos and two of three in Viet Nam were confirmed positive for African swine fever virus using real-time PCR. There were no confirmed reports of wild boar carcasses in Cambodia. This is the first confirmation of ASF in wild boar in Southeast Asia, the result of a probable viral spillover from domestic pigs, which highlights the importance of early reporting and monitoring of ASF in wild boar to enable the implementation of appropriate biosecurity measures.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos/virologia , Febre Suína Africana/diagnóstico , Febre Suína Africana/epidemiologia , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/isolamento & purificação , Animais , Camboja , Laos , Fatores de Risco , Sus scrofa/virologia , Vietnã
8.
PLoS One ; 15(8): e0237129, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32776964

RESUMO

Outbreaks of emerging coronaviruses in the past two decades and the current pandemic of a novel coronavirus (SARS-CoV-2) that emerged in China highlight the importance of this viral family as a zoonotic public health threat. To gain a better understanding of coronavirus presence and diversity in wildlife at wildlife-human interfaces in three southern provinces in Viet Nam 2013-2014, we used consensus Polymerase Chain Reactions to detect coronavirus sequences. In comparison to previous studies, we observed high proportions of positive samples among field rats (34.0%, 239/702) destined for human consumption and insectivorous bats in guano farms (74.8%, 234/313) adjacent to human dwellings. Most notably among field rats, the odds of coronavirus RNA detection significantly increased along the supply chain from field rats sold by traders (reference group; 20.7% positivity, 39/188) by a factor of 2.2 for field rats sold in large markets (32.0%, 116/363) and 10.0 for field rats sold and served in restaurants (55.6%, 84/151). Coronaviruses were also detected in rodents on the majority of wildlife farms sampled (60.7%, 17/28). These coronaviruses were found in the Malayan porcupines (6.0%, 20/331) and bamboo rats (6.3%, 6/96) that are raised on wildlife farms for human consumption as food. We identified six known coronaviruses in bats and rodents, clustered in three Coronaviridae genera, including the Alpha-, Beta-, and Gammacoronaviruses. Our analysis also suggested either mixing of animal excreta in the environment or interspecies transmission of coronaviruses, as both bat and avian coronaviruses were detected in rodent feces on wildlife farms. The mixing of multiple coronaviruses, and their apparent amplification along the wildlife supply chain into restaurants, suggests maximal risk for end consumers and likely underpins the mechanisms of zoonotic spillover to people.


Assuntos
Animais Selvagens/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Coronavirus/genética , Carne/virologia , Zoonoses/epidemiologia , Zoonoses/transmissão , Animais , Quirópteros/virologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Reservatórios de Doenças/virologia , Fezes/virologia , Abastecimento de Alimentos , Humanos , Filogenia , Reação em Cadeia da Polimerase , Porcos-Espinhos/virologia , RNA Viral/genética , Ratos , Risco , Vietnã/epidemiologia , Zoonoses/diagnóstico , Zoonoses/virologia
9.
Phytopathology ; 102(7): 674-82, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22667446

RESUMO

Barley cultivars show various patterns of resistance against isolates of Magnaporthe oryzae and M. grisea. Genetic mechanisms of the resistance of five representative barley cultivars were examined using a highly susceptible barley cultivar, 'Nigrate', as a common parent of genetic crosses. The resistance of the five cultivars against Setaria, Oryza, Eleusine, and Triticum isolates of M. oryzae was all attributed to a single locus, designated as Rmo2. Nevertheless, the Rmo2 locus in each cultivar was effective against a different range of isolates. Genetic analyses of pathogenicity suggested that each cultivar carries an allele at the Rmo2 locus that recognizes a different range of avirulence genes. One allele, Rmo2.a, corresponded to PWT1, which conditioned the avirulence of Setaria and Oryza isolates on wheat, in a gene-for-gene manner. The other alleles, Rmo2.b, Rmo2.c, and Rmo2.d, corresponded to more than one avirulence gene. On the other hand, the resistance of those cultivars to another species, M. grisea, was conditioned by another locus, designated as Rmo3. These results suggest that Rmo2 is effective against a broad range of blast isolates but is specific to M. oryzae. Molecular mapping revealed that Rmo2 is located on the 7H chromosome.


Assuntos
Resistência à Doença/genética , Loci Gênicos , Hordeum/genética , Interações Hospedeiro-Patógeno/genética , Magnaporthe/fisiologia , Alelos , Mapeamento Cromossômico , Genes de Plantas , Hordeum/microbiologia , Doenças das Plantas
10.
Phytopathology ; 100(5): 436-43, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20373964

RESUMO

The pathogenicity to wheat (Pwt1) locus conditions host species specificity of Magnaporthe oryzae on wheat. GFSI1-7-2 (Setaria isolate) carries the avirulence allele (PWT1) at this locus while Br48 (Triticum isolate) carries the virulence allele (pwt1). An F(1) culture derived from a cross between GFSI1-7-2 and Br48 was backcrossed with Br48 to produce a tester population in which PWT1 alone segregated. When hexaploid wheat lines were inoculated with the BC(1)F(1) testers, they were all resistant to all PWT1 carriers and susceptible to all pwt1 carriers, suggesting that they recognize PWT1. When barley cultivars were inoculated with the testers, they showed the same pattern of reactions as the hexaploid lines, suggesting that the barley cultivars also recognize PWT1. These results suggest that PWT1 is a fundamental gene that universally conditions the avirulence of Setaria isolates on two staple crops, hexaploid wheat and barley. Interestingly, tetraploid wheat lines did not recognize PWT1. Molecular mapping using the F(1) and BC(1)F(1) populations revealed that the Pwt1 locus is located on chromosome 2 and tightly linked to the ribosomal DNA locus and a telomere.


Assuntos
DNA Fúngico/genética , DNA Ribossômico/genética , Hordeum/microbiologia , Magnaporthe/genética , Magnaporthe/metabolismo , Triticum/microbiologia , Mapeamento Cromossômico , Cromossomos Fúngicos , Interações Hospedeiro-Patógeno , Magnaporthe/patogenicidade , Doenças das Plantas , Especificidade da Espécie , Virulência
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