Is Ornithodoros erraticus able to transmit the Georgia2007/1 African Swine Fever virus isolate to domestic pigs?

Objective: African swine fever, one of the most devastating diseases affecting wild and domestic swine, is due to a large DNA virus, only member of the Asfarviridae family. After ASF introduction in Georgia in 2007, the disease became endemic in the Caucasian region of the Russian Federation and spread towards the Western regions of Europe entering in EU Members States at the beginning of 2014. As no vaccine or antiviral are available to fight against this infection, the only tools to control it are preventive measures based on early detection and actual knowledge of the epidemiological risks. In African sub-Saharan countries, ASF persistence is described to be related to different and complex epidemiological scenarii involving domestic and wild suids and soft tick vectors of the genus Ornithodoros. In EU, one species of Ornithodoros, O. erraticus, is known to be able to maintain and/or transmit some ASFV isolates classified in the genotype I. Recently, the Pirbright Institute also demonstrated that O. erraticus was able to amplify the Georgia2007/1 ASFV (genotype II), at least during 3 months. The objective of the current study was to evaluate the in- vitro and in-vivo transmissibility of the Georgia 2007/1 ASFV by infected O. erraticus ticks. Methods: The Georgia 2007/1 ASFV strain belonging to the genotype II, kindly provided by L. Dixon (OIE reference lab), was grown on porcine pulmonary alveolar macrophages to the titre of 106to 107 HAD50 , then diluted 100-fold into pig blood for tick infection or 1000-fold in medium for intradermal inoculation to pigs. Ticks were captured in Portugal by F. Boinas and mass reared at CIRAD for one year and a half to obtain a stable and mature population. During this period, several techniques of artificial feeding were tested to optimize the method. In December 2014, 60 adults or last nymphal stages -group A- coming both from field and 1st generation laboratory were artificially engorged on pig blood supplemented with Georgia 2007/1 at a final titre of 104.5 HAD50/mL blood. Two other groups of ASFV-free ticks –group B with 60 individuals and group C with 30 individuals- were reared to be used for a second infection directly on infected pigs (group B) and as control group (group C), respectively. Moreover to confirm the possibility to infect ticks through artificial blood meal, another group of 10 ticks was also engorged and tested for virus multiplication three months later. Fifteen other females were also infected and secondarily engorged on ASFV-free pig blood to test in-vitro transmission through virus isolation on second blood meal. Considering that it is difficult to obtain ASFV titres with in-vitro cultivation as high as in infected pigs developing ASFV clinical signs, it seems important to compare ASFV transmissibility between ticks artificially infected in laboratory and ticks directly infected on ASFV-infected pigs and conclude on possible dose effect. In March 2015, 18 Large-White pigs obtained from a high sanitary level field herd were distributed to 4 groups at Anses-Ploufragan high security facilities. Two negative control groups of 3 pigs were either intra-dermally inoculated with MEM or bitten by group C of 30 healthy ticks. One group of 6 pigs was intra-dermally inoculated with 103 HAD50 ASFV while the last group of 6 pigs was bitten by group A of 60 ticks previously infected through artificial blood meal and dispatched in 10 ticks/pig. Pots of 10 ticks were placed on one ear held there with adhesive tape, then removed after 3 hours. After removal, ticks were numbered in two batches: engorged and unengorged ticks. Finally, as soon as the 6 pigs intra-dermally inoculated with ASFV showed fever and high viremiae, group B of 60 ASFV-free ticks were proposed to engorge on their opposite ear. These ticks would be proposed to secondarily engorge on membrane feeding or healthy pigs three months later. Post tick feeding or intradermal inoculation, clinical examination and rectal temperatures were recorded daily, until the animals were euthanized or for a minimum period of 18 days. Except on D1 pi, serum and EDTA blood samples were daily collected from all the pigs during the first week pi, then twice a week during the 2 following weeks, and at the day of euthanasia for virological and serological assays. Organ samples were collected during necropsy. The animal experiment protocol was approved by the French national ethics committee ComEth Anses/ENVA/UPEC (10/03/15-9). Results: Ten ticks from the original batch of ticks that were artificially fed on infectious blood were tested by virus titration. Out of them, 8 were positive with a titre ranging from 102 to 104.2 HAD50/tick and 2 ticks clearly amplified the virus regarding the estimated amount of virus originally ingested (minimum of 1 log superior). After feeding on pigs, the mean level of engorged ticks was of 62%, whatever the group of pigs. The experiment, currently running, confirmed the high virulence of the Georgia strain as all the 6 intra-dermally inoculated pigs displayed typical symptoms of ASF including lost of appetite and hyperthermia from D3 pi. The 6 pigs were euthanized from D5 to D7. The group of the 6 pigs bitten by the infected ticks was still healthy at 18 days post feeding, as well as the two negative control groups. However, among the 15 female ticks secondarily engorged on ASFV-free pig blood, no heamadsorption effect was observed after two passages on alveolar macrophage culture using blood-meal leftovers. Further investigations are needed to confirm the presence of ASF Virus. The final experimental infection of pigs through tick bite using ticks previously engorged on viremic pigs should allow concluding on the ability of O. erraticus to transmit Georgia2007/1 and a possible dose effect on this transmissibility. The results will be presented and discuss during the symposium. Conclusion: The objective of this study was to experimentally assess the ability of the European O. erraticus tick to transmit the Georgia 2007/1 ASFV currently circulating in North-Eastern EU. First results showed that ticks artificially infected in laboratory did not induce ASF clinical signs in pigs by biting. However, virus titration in ticks seems to show that the virus is present in the arthropod. Further in-vitro and in-vivo investigations are running to explore the hypothesis of a dose effect. The expected results should clarify the potential epidemiological role of O. erraticus ticks in transmission and re-emergence of ASFV in the field, in case of the spread of current active foci from North-Eastern EU. (Résumé d'auteur

Transmission routes of African swine fever virus to domestic pigs: current knowledge and future research directions

African swine fever (ASF) is a major threat to the pig industry in Europe. Since 2007, ASF outbreaks have been ongoing in the Caucasus, Eastern Europe and the Baltic countries, causing severe economic losses for many pig farmers and pork producers. In addition, the number of ASF cases in wild boar populations has dramatically increased over the past few years. Evidence supports direct contact with infectious domestic pigs and wild boars, and consumption of contaminated feed, as the main transmission routes of ASF virus (ASFV) to domestic pigs. However, significant knowledge gaps highlight the urgent need for research to investigate the dynamics of indirect transmission via the environment, the minimal infective doses for contaminated feed ingestion, the probability of effective contacts between infectious wild boars and domestic pigs, the potential for recovered animals to become carriers and a reservoir for transmission, the potential virus persistence within wild boar populations and the influence of human behaviour for the spread of ASFV. This will provide an improved scientific basis to optimise current interventions and develop new tools and strategies to reduce the risk of ASFV transmission to domestic pigs.ISSN:0042-490

A survey on knowledge and practices of brucellosis among occupationally exposed livestock workers in Namibe province, Angola

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Mosquito (Diptera: Culicidae) Fauna of a Zoological Park in an Urban Setting: Analysis of Culex pipiens s.l. and Their Biotypes

(This article belongs to the Special Issue Insect Vectors of Human and Zoonotic Diseases)Mosquito-borne diseases (MBDs) are important emerging diseases that affect humans and animals. Zoological parks can work as early warning systems for the occurrence of MBDs. In this study, we characterized the mosquito fauna captured inside Lisbon Zoo from May 2018 to November 2019. An average of 2.4 mosquitos per trap/night were captured. Five mosquito species potentially causing MBDs, including Culex pipiens biotypes, were found in the zoo. The sympatric occurrence of Culex pipiens biotypes represents a risk factor for the epizootic transmission of West Nile virus and Usutu virus. The mosquito occurrence followed the expected seasonality, with the maximum densities during summer months. However, mosquito activity was detected in winter months in low numbers. The minimum temperature and the relative humidity (RH) on the day of capture showed a positive effect on Culex pipiens abundance. Contrary, the RH the week before capture and the average precipitation the week of capture had a negative effect. No invasive species were identified, nor have flaviviruses been detected in the mosquitoes. The implementation of biosecurity measures regarding the hygiene of the premises and the strict control of all the animals entering the zoo can justify the low prevalence of mosquitoes and the absence of flavivirus-infected mosquitoes.This research was funded by FCT—Fundação para a Ciência e a Tecnologia, I.P., through the project grants UIDB/00276/2020 (CIISA—Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Lisboa, Portugal), and LA/P/0059/2020 (AL4AnimalS—Laboratório Associado para Ciência Animal e Veterinária). The author Sara Madeira was supported by an FCT Ph.D. fellowship SFRH/BD/117431/2016.info:eu-repo/semantics/publishedVersio

Centros de serviços partilhados : conceito, evolução e desafios atuais : quatro centros localizados em Portugal

O modelo de centros de serviços partilhados que se caracteriza pela concentração da gestão de serviços não estratégicos numa única unidade organizacional (Schulman et al., 1999), tem vindo a aumentar nos últimos anos em Portugal, sendo o nosso país cada vez mais escolhido por grandes grupos económicos multinacionais para montar os seus centros. O trabalho desenvolvido visa dar conta da realidade destes centros explicando as suas permissas e as razões de escolha de Portugal como destino. Para tal, procurando perceber também de que forma é que esta decisão impactou o desempenho e o desenvolvimento estratégico destes centros. De forma a atingir os objetivos supramencionados, desenvolveu-se um estudo de caso que abrangeu a quatro empresas multinacionais estrangeiras que implementaram os seus centros de serviços partilhados (doravante designados por “CSP”) em Portugal. A análise desenvolvida permitiu concluir que as principais razões para a localização de serviços partilhados em Portugal são os baixos custos de implementação e funcionamento dos CSP, a formação académica e as competências linguísticas dos colaboradores. Decorridos alguns anos desde a instalação destes CSP em Portugal, constata-se que os resultados alcançados por estes centros se enquadram nas expetativas inicialmente estabelecidas por parte das sedes dessas multinacionais, prevendo-se em todos os casos a expansão destes centros num futuro próximo.The model of shared services characterized by the concentration of the of non-strategic management services in a single organizational unit (Schulman et al., 1999), has increased in Portugal over the last years. Our country has been progressively selected by large multinational economic groups to present their centres. The work herein carry out intends to assess the reality of the afore-mentioned centres for shared services, explaining its premises and the reasons for which Portugal has been chosen as a destination thereof. To this effect, this study further aims to understand the extent to which this decision - i.e. the selection of Portugal as the setting for the presentation and divulgation of the said centers for shared services - affected the performance and strategic development of such centers. With the purpose of achieving the objectives indicated supra, this work developed and scrutinised a case study centred on four foreign multinational enterprises that implemented the respective centers of shared services (hereinafter, “CSP”)in Portugal. The analysis caried out led to the conclusion that the main reasons for establishing shared services in Portugal are the low costs associated with the implementation and functioning of CSP as well as the academic backgroundand linguaje skills of collaborators. Few years following the establishment of these CSP in Portugal, one can verify that the results obtained meet the expectations initially determined by the headquarters of the multinational companies concerned. It is foreseen that all these centers will meet expansion in the near future

Comportamentos autolesivos em amostra de adolescentes da Cova da Beira – estudo comparativo pré e pós-pandemia COVID-19

Introdução: Os comportamentos autolesivos (CAL) compreendem ações sem intenção suicidária em que um indivíduo provoca lesões a si mesmo ou ingere substâncias prejudiciais com intenção de autolesão. Esses comportamentos são patológicos, sendo considerados um importante preditor de suicídio. A pandemia de COVID-19 tem sido associada a um aumento nas perturbações da saúde mental, especialmente em adolescentes. Assim, o objetivo do estudo consistiu em avaliar a prevalência, caracterizar padrões dos CAL e investigar fatores de risco associados, incluindo o impacto da pandemia em adolescentes, e propor medidas preventivas. Materiais e métodos: Foi desenvolvido um estudo transversal baseado num questionário aplicado em consulta de Pediatria de um hospital de nível II. A amostra totalizou 319 questionários (159 em 2019; 160 em 2023) preenchidos por adolescentes entre os 12 e 18 anos. A análise estatística envolveu regressão logística para análises univariada e multivariada ajustada. Resultados: A prevalência dos CAL obtida nos dois períodos foi de 29,78% (n=95), verificando-se um aumento de 7,96% no período pós-pandémico, mas não significativo (p=0,121). O método mais frequentemente utilizado foram cortes (72,63%), predominantemente nos membros superiores (84,06%). Entre os jovens com CAL, 34,74% procuraram ajuda, principalmente de irmãos/amigos (72,73%). Acrescente-se que 42,1% referiram que efetuaram estes comportamentos devido ao desejo de morrer e 15,8% referiram querer chamar a atenção. Na regressão logística multivariada, os fatores de risco que se revelaram significativos incluíram problemas de saúde, ausência de exercício físico, ser ex-fumador, conflitos com namorado/a, história de suicídio tentado ou CAL na família/amigos e procura online de formas de se magoar. A exposição a eventos de vida negativos correlacionou-se significativamente com CAL, incluindo dificuldade em fazer amigos, bullying, conflitos parentais, abusos físicos/agressões/violência, preocupações com orientação sexual e relações sexuais não consensuais. Também foi significativo o consumo de drogas e alcoolização = 2 vezes/mês, bem como apresentar um baixo índice de bem-estar da OMS. Conclusão: Sendo os CAL importantes preditores de suicídio, urge incrementar a literacia em saúde mental, combatendo o estigma e incentivando a procura de ajuda pelos adolescentes, nomeadamente de profissionais qualificados.Introduction: Deliberate self-harm (DSH) encompass non-suicidal actions where an individual intentionally inflicts injuries or ingests harmful substances for self-harm. These behaviors are consistently considered pathological and are regarded as a significant predictor of suicide. The COVID-19 pandemic has been associated with an increase in mental health disorders, especially among adolescents. The study aimed to assess prevalence, characterize DSH patterns, investigate associated risk factors, including the impact of the pandemic on adolescents, and propose preventive measures. Methods and Materials: A cross-sectional study was conducted based on a questionnaire administered in the Pediatrics outpatient clinic of a level II hospital. The sample comprised 319 questionnaires (159 in 2019; 160 in 2023) from adolescents aged 12 to 18. Statistical analysis involved logistic regression for univariate and adjusted multivariate analyses. Results: The prevalence of DSH in both periods was 29,78% (n=95), with a 7,96% increase in the post-pandemic period but not significative (p=0,121). The most frequently used method was cuts (72,63%), predominantly on the upper limbs (84,06%). Among adolescents with DSH, 34,74% sought help, mainly from siblings/friends (72,73%). Additionally, 42,1% expressed a desire to die, and 15,8% mentioned seeking attention. In multivariate logistic regression, significant risk factors included health problems, lack of physical exercise, former smoking, conflicts with a partner, a history of attempted suicide or DSH in family/friends, and online search for self-harm methods. Exposure to negative life events correlated significantly with DSH, including difficulty making friends, bullying, parental conflicts, physical abuse/aggression/violence, concerns about sexual orientation, and non-consensual sexual relationships. Drug consumption, alcohol intake = 2 times/month, and a low WHO well-being index were also significant. Conclusion: Given that DSH is a significant predictor of suicide, there is an urgent need to increase mental health literacy, combat stigma, and encourage adolescents to seek help from qualified professionals