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In recent years, the concept of One Health (OH) has arisen as an approach that helps to catalyze the creation of transdisciplinary teams needed for surveillance and investigation of emerging disease dynamics. Besides a wealth of descriptions of what the OH approach encompasses, a dearth of information is available regarding the training of individuals in OH competencies. In 2019, the Nigerian Center for Disease Control developed an OH strategic plan to meet the country's human, animal, and environmental health challenges. In response to the demand for clinicians, scientists, climatologists, conservationists, and environmentalists, who have expertise in environment, human, plant, and animal health to work collaboratively in addressing OH challenges in Nigeria. An interprofessional group of faculty from the University of Texas Medical Branch, the University of Jos, and the National Veterinary Research Institute convened to develop a novel OH course 'entitled 'One Health for Translational Team Science. The objective of the course was to explore the evolution of an emerging epidemic, capitalizing on various learning environments, including animal, environmental, human, and public health perspectives. The 6-week course comprised of three parts: 2-weeks virtual part of case-based group discussions focusing on animal and environmental aspects, 2 weeks of individual field experiences, and a final virtual part focusing on human health. Pedagogical tools used were: case-based group discussions, breakout group presentations, role-play activities, field project write-up, peer evaluation, group writing assignments, and weekly reflections with the goal of working in teams to develop and practice the fundamental leadership and management skills in addressing emerging public health challenges. Post-course evaluations showed that all participants felt more confident identifying and practicing the necessary attitudes and skills to participate effectively in the evaluation of an outbreak. Furthermore, the roles, responsibilities, and "One Health ways of thinking" for the various disciplines and professions involved in improving global health were articulated and identified.
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Saúde Única , Nigéria , Humanos , Currículo , Relações Interprofissionais , Política de Saúde , Comportamento CooperativoRESUMO
Anthrax is a zoonotic bacterial disease caused by Bacillus anthracis. It poses significant threat to humans through contact with infected animals or their by-products. Concerns arise from its long-lasting spore viability and lethality, fuelling its biowarfare potential. Recent anthrax outbreaks across multiple African nations prompted this bibliometric study. The aim of the study was to assess the contributions of African countries, institutions, authors, research funding, and collaborations, while identifying research trends and gaps. We conducted an extensive bibliometric analysis of anthrax-related research publications in Africa from 1923 to 2023, utilizing the Scopus database and VOSviewer. The study covered 364 publications from 32 African countries, accumulating 5,636 citations at an average of 15.5 citations per article, with research articles comprising 88.5% of the corpus. The publication growth rate from 1923 to 2023 was modest at 8.3%, indicating gradual advancement. Notably, there was a significant surge in publications between 2011 and 2023, accounting for 73.1% of total publications. The African research contributions, were categorized into five thematic focuses: ecological dynamics and host interactions, human-livestock anthrax interface, molecular insights into bacterial activity and treatment strategies, collaborative approaches for zoonotic disease prevention, and antibody response and vaccination strategies. Leading institutional contributors included the University of Pretoria and the University of KwaZulu-Natal. Collaborations extended globally to 35 non-African countries, with significant involvement from the United States, United Kingdom, and Germany. Strong African partnerships, especially between Kenya, Nigeria, and South Africa, emerged. The top 10 cited papers explored diverse aspects, including disease impact on wildlife and innovative control strategies, underscoring the importance of multidisciplinary approaches. South Africa played a prominent role, contributing 95 publications and securing funding from various sources, including the National Research Foundation. Collaborations with global institutions highlighted its commitment. This study unveils the dynamic landscape of anthrax research in Africa, emphasizing the pivotal role of collaboration, multidisciplinary One Health approaches, and global partnerships in enhancing research outcomes. Ongoing research and practical solutions for human and animal health remain imperative.
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The global spread of African swine fever (ASF) in recent decades has led to the need for technological advances in sampling and diagnostic techniques. The impetus for these has been the need to enable sampling by lay persons and to obtain at least a preliminary diagnosis in the field for early control measures to be put in place before final laboratory confirmation. In rural Africa, rapid diagnosis is hampered by challenges that include lack of infrastructure as well as human and financial resources. Lack of animal health personnel, access to affordable means to transport field samples to a laboratory, and lack of laboratories with the capacity to make the diagnosis result in severe under-reporting of ASF, especially in endemic areas. This review summarizes the challenges identified in gap analyses relevant to low- and middle-income countries, with a focus on Africa, and explore the opportunities provided by recent research to improve field diagnosis and quality of diagnostic samples used. Sampling techniques include invasive sampling techniques requiring trained personnel and non-invasive sampling requiring minimal training, sampling of decomposed carcass material, and preservation of samples in situations where cold chain maintenance cannot be guaranteed. Availability and efficacy of point-of-care (POC) tests for ASF has improved considerably in recent years and their application, as well as advantages and limitations, are discussed. The adequacy of existing laboratory diagnostic capacity is evaluated and opportunities for networking amongst reference and other laboratories offering diagnostic services are discussed. Maintaining laboratory diagnostic efficiency in the absence of samples during periods of quiescence is another issue that requires attention, and the role of improved laboratory networking is emphasized. Early diagnosis of ASF is key to managing the disease spread. Therefore, the establishment of the Africa Chapter of the Global African Swine Fever Research Alliance (GARA) increases opportunities for collaboration and networking among the veterinary diagnostic laboratories in the region.
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Introduction: Haemophilus influenzae type b (Hib) causes invasive infections almost exclusively in under- fives with those aged 6-23 months being the most vulnerable. In Nigeria, it is estimated to cause nearly 400,000 annual infections and another 30,000 under-five mortality attributable to pneumonia and meningitis alone. The Hib Conjugate Vaccine (HCV) is in widespread use to combat these devastating infections. Data on its impact in Nigeria is grossly scanty. This study evaluated the seroprotection rates (SPR) of HCV and associated clinical outcomes among children aged 6-23 months in Obi L.G.A. of Nasarawa State, Nigeria. Methods: A cross-sectional study of 267 children aged 6-23 months who had completed three doses of HCV. They were enrolled via a two-staged household-level cluster sampling. Relevant sociodemographic and clinical data were obtained using structured questionnaires and serum samples collected were analysed serologically for antipolyribosylribitol phosphate (anti-PRP) antibodies using ELISA. Results: The overall SPRs against invasive Hib disease and Hib nasopharyngeal colonization were 74.2% and 26.2%, respectively. The overall geometric mean titre (GMT) of anti-PRP was 1.85 µg/mL (95%CI: 1.60-2.14) and across age groups, GMTs were >1 µg/mL-the threshold for long-term protection against invasive Hib disease. Rates/duration of healthcare admissions and average episodes of probable Hib disease syndromes were lower in seroprotected but not statistically different from non-seroprotected children. Conclusion: The demonstrated anti-PRP titres and Seroprotection Rates infer a very good HCV efficacy in Nigerian children. The lack of significant difference in clinical outcomes may be attributable to nonspecificity.
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Infecções por Haemophilus , Vacinas Anti-Haemophilus , Haemophilus influenzae tipo b , Hepatite C , Criança , Humanos , Lactente , Infecções por Haemophilus/epidemiologia , Infecções por Haemophilus/prevenção & controle , Vacinas Conjugadas , Estudos Transversais , Anticorpos AntibacterianosRESUMO
Outbreaks of African Swine Fever (ASF) have severe economic implications for Nigeria and result in significant loss of livelihoods. The non-availability of vaccines makes biosecurity the reliable key to reducing ASF outbreaks. This study evaluated preparedness for ASF outbreaks at the farm level among 247 pig farmers randomly selected from Abia, Akwa-Ibom, Edo, Kwara, and Oyo states. We categorized each pig farmer's ASF preparedness rating (ASF - PR) as "poor", "moderate", and "satisfactory" based on their score on an 11-item scale. Finally, a multivariable logistic regression analysis was conducted to assess the association between the socio-demographic variables and farm-level ASF preparedness. The awareness of ASF among pig farmers was very high (87.9%, n = 217). Most farmers knew the clinical signs of the disease, the modes of transmission of ASF, and correctly identified the risk factors. They also considered the need for thorough cleaning and disinfection of piggeries (87.1%, n = 189), tightened biosecurity (85.7%, n = 186), culling all ASF-affected pigs (77.9%, n = 169) as well as the ban on the transport of pigs and their products (49.8%, n = 108) as very important in ASF control. Conversely, 27.6%, (n = 60) of the farmers thought ASF could affect humans, 12% (n = 27) of them openly discarded the carcasses of dead pigs, and there was a high antibiotic usage. Most of the pig farmers used antibiotics as prophylaxis (63.6%, n = 157), chemotherapeutics (66.4%, n = 164), growth promoters (15.4%, n = 38), and wrongly so, 13% (n = 32) of them thought that antibiotics could be used to prevent and treat ASF. At the farm level, two-thirds (68.8%, n = 170) of the farmers had strict movement restrictions, and 48.6% (n = 120) routinely quarantine new pigs before introduction into their herd. Across the five states, 36% (n = 89) of the farmers had witnessed sudden death with signs consistent with ASF amongst their pigs and only 10.1% (n = 27) had confirmatory ASF diagnosis. The mean score for the farm-level ASF-PR was 6.95 ± 2.7. Approximately one-quarter of the 247 pig farmers had satisfactory ASF - PR that might help to prevent the incursion of ASF into their farms. Most farmers had moderate ASF - PR (59.5%, n = 147) whereas 17% (n = 42) had very poor ASF-PR and were most prone to an ASF outbreak. Of the sociodemographic variables, only age was significantly associated with farm-level ASF preparedness as older pig farmers especially those aged between 50 and 59 years (OR: 4.83; 95% CI: 1.10, 21.22; p = 0.037) were more likely to have satisfactory ASF - PR than the others. Our findings showed pig farmers were not adequately prepared and the next ASF outbreak could pose more significant threat to pig populations across Nigeria. Government should urgently establish minimum biosecurity measures and improve its ASF surveillance mechanisms for commercial and backyard pig production.
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Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Humanos , Animais , Pessoa de Meia-Idade , Febre Suína Africana/epidemiologia , Febre Suína Africana/prevenção & controle , Fazendas , Nigéria/epidemiologia , Criação de Animais Domésticos , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , AntibacterianosRESUMO
African swine fever (ASF) is a contagious viral disease that affects domestic pigs and wild boars, causing significant economic losses globally. After the first Nigerian outbreak in 1997, there have been frequent reports of ASF in pig-producing regions in the country. To facilitate control, it is important to understand the genotype and phylogenetic relationship of ASF viruses (ASFVs). Recent genetic analysis of Nigerian ASFV isolates has revealed the presence of both genotypes I and II; this is based on analysis of a few selected genes. Phylogenetic analysis of ASFV whole genomes highlights virus origins and evolution in greater depth. However, there is currently no information on the ASFV genome from Nigerian isolates. Two ASFV-positive samples were detected during a random survey of 150 Nigerian indigenous pig samples collected in 2016. We assembled near-complete genomes of the two ASFV-positive samples using in-solution hybrid capture sequencing. The genome-wide phylogenetic tree assigned these two genomes into p72 genotype I, particularly close to the virulent Benin 97/1 strain. The two ASFVs share 99.94 and 99.92â% genomic sequence identity to Benin97/1. This provides insight into the origin and relationship of ASFV strains from Nigeria and Italy. The study reports for the first time the determination of near-complete genomes of ASFV using in-solution hybrid capture sequencing, which represents an important advance in understanding the global evolutionary landscape of ASFVs.
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Febre Suína Africana , Suínos , Animais , Filogenia , Genótipo , Genômica , Surtos de Doenças , Sus scrofaRESUMO
Lumpy Skin disease (LSD) is an economically important disease in cattle caused by the LSD virus (LSDV) of the genus Capripoxvirus, while pseudocowpox (PCP) is a widely distributed zoonotic cattle disease caused by the PCP virus (PCPV) of the genus Parapoxvirus. Though both viral pox infections are reportedly present in Nigeria, similarities in their clinical presentation and limited access to laboratories often lead to misdiagnosis in the field. This study investigated suspected LSD outbreaks in organized and transhumance cattle herds in Nigeria in 2020. A total of 42 scab/skin biopsy samples were collected from 16 outbreaks of suspected LSD in five northern States of Nigeria. The samples were analyzed using a high-resolution multiplex melting (HRM) assay to differentiate poxviruses belonging to Orthopoxvirus, Capripoxvirus, and Parapoxvirus genera. LSDV was characterized using four gene segments, namely the RNA polymerase 30 kDa subunit (RPO30), G-protein-coupled receptor (GPCR), the extracellular enveloped virus (EEV) glycoprotein and CaPV homolog of the variola virus B22R. Likewise, the partial B2L gene of PCPV was also analyzed. Nineteen samples (45.2%) were positive according to the HRM assay for LSDV, and five (11.9%) were co-infected with LSDV and PCPV. The multiple sequence alignments of the GPCR, EEV, and B22R showed 100% similarity among the Nigerian LSDV samples, unlike the RPO30 phylogeny, which showed two clusters. Some of the Nigerian LSDVs clustered within LSDV SG II were with commonly circulating LSDV field isolates in Africa, the Middle East, and Europe, while the remaining Nigerian LSDVs produced a unique sub-group. The B2L sequences of Nigerian PCPVs were 100% identical and clustered within the PCPV group containing cattle/Reindeer isolates, close to PCPVs from Zambia and Botswana. The results show the diversity of Nigerian LSDV strains. This paper also reports the first documented co-infection of LSDV and PCPV in Nigeria.
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Capripoxvirus , Doenças dos Bovinos , Vírus da Doença Nodular Cutânea , Infecções por Poxviridae , Animais , Bovinos , Nigéria/epidemiologia , Fazendas , Vírus da Doença Nodular Cutânea/genética , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/veterinária , Infecções por Poxviridae/diagnóstico , Doenças dos Bovinos/epidemiologia , Surtos de Doenças/veterinária , Zoonoses , FilogeniaRESUMO
African swine fever (ASF) is a high-consequence transboundary hemorrhagic fever of swine. It continues to spread across the globe causing socio-economic issues and threatening food security and biodiversity. In 2020, Nigeria reported a major ASF outbreak, killing close to half a million pigs. Based on the partial sequences of the genes B646L (p72) and E183L (p54), the virus responsible for the outbreak was identified as an African swine fever virus (ASFV) p72 genotype II. Here, we report further characterization of ASFV RV502, one of the isolates obtained during the outbreak. The whole genome sequence of this virus revealed a deletion of 6535 bp between the nucleotide positions 11,760-18,295 of the genome, and an apparent reverse complement duplication of the 5' end of the genome at the 3' end. Phylogenetically, ASFV RV502 clustered together with ASFV MAL/19/Karonga and ASFV Tanzania/Rukwa/2017/1 suggesting that the virus responsible for the 2020 outbreak in Nigeria has a South-eastern African origin.
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Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/genética , Febre Suína Africana/epidemiologia , Sus scrofa , Nigéria/epidemiologia , Análise de Sequência de DNA , Filogenia , Genótipo , Surtos de DoençasRESUMO
African wild suids consist of several endemic species that represent ancient members of the family Suidae and have colonized diverse habitats on the African continent. However, limited genomic resources for African wild suids hinder our understanding of their evolution and genetic diversity. In this study, we assembled high-quality genomes of a common warthog (Phacochoerus africanus), a red river hog (Potamochoerus porcus), as well as an East Asian Diannan small-ear pig (Sus scrofa). Phylogenetic analysis showed that common warthog and red river hog diverged from their common ancestor around the Miocene/Pliocene boundary, putatively predating their entry into Africa. We detected species-specific selective signals associated with sensory perception and interferon signaling pathways in common warthog and red river hog, respectively, which contributed to their local adaptation to savannah and tropical rainforest environments, respectively. The structural variation and evolving signals in genes involved in T-cell immunity, viral infection, and lymphoid development were identified in their ancestral lineage. Our results provide new insights into the evolutionary histories and divergent genetic adaptations of African suids.
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Adaptação Fisiológica , Animais , Suínos , Filogenia , Especificidade da Espécie , Adaptação Fisiológica/genética , ÁfricaRESUMO
Marek's disease (MD) is a devastating neoplastic disease of poultry caused by MD virus (MDV). MD is one of the several diseases limiting the thriving Nigerian poultry industry. MD is mostly diagnosed in Nigeria based on history and gross lesions without laboratory investigations leading to underreporting of the disease. This study investigated MD outbreaks in poultry farms using polymerase chain reaction (PCR) and histopathology. Tumourous visceral organs were collected from dead chickens presented to veterinary clinics from 110 farms in Plateau State, North Central Nigeria from April 2013 to August 2014. Clinical signs observed in affected chickens were paralysis, stunting and uneven growth. Whilst the gross lesions observed were hepatomegaly, splenomegaly with lymphoma, prominent peripheral nerves and cachexia. The meq gene of MDV1 was detected by PCR in 55.0% (n = 11/20) of broilers and 71.1% (n = 64/90) of vaccinated layer chicken samples collected. Microscopy revealed severe diffuse lymphocytic infiltrations in the heart, spleen and liver of chickens with tumourous gross lesions. Based on history, gross lesions, detection of meq gene of MDV1 by PCR and histopathology results, MD was confirmed in the affected farms. Despite vaccination, outbreaks of MD still occurs in poultry farms in Nigeria. This study represents the first confirmatory diagnosis of MD in vaccinated poultry in Nigeria.
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Doença de Marek , Doenças das Aves Domésticas , Animais , Doença de Marek/epidemiologia , Aves Domésticas , Nigéria/epidemiologia , Galinhas , Fazendas , Surtos de Doenças/veterináriaRESUMO
Toxoplasmosis has been reported in Nigeria using several diagnostic tools with high prevalence in humans and some food animals. Rodents have been recognised as vital intermediate hosts of Toxoplasma gondii. However, there is paucity of information on the occurrence of T. gondii in wild rats found in Nigeria. This study aimed at molecular detection of T. gondii in Zyzomys pedunculatus and to evaluate its involvement in the epidemiology of toxoplasmosis in Nigeria. A total of 84 rats were sampled across three states of the North Central Nigeria, and DNA was extracted from the brain, lungs, kidney and intestine of the rats for the detection of T. gondii DNA by nested PCR to amplify the multicopy B1 gene. Sixty-four of the 84 samples (76.2%) were positive for T. gondii out of which 5 samples were sequenced and had an identity score of between 97.73% and 99.35% with the reference B1 gene of T. gondii in GenBank. This study suggests Nigerian wild rats may be an important intermediate hosts of T. gondii and may play a role in the epidemiology and maintenance of T. gondii circulation in Nigeria.
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Doenças dos Roedores , Toxoplasma , Toxoplasmose Animal , Animais , DNA de Protozoário/análise , Humanos , Nigéria/epidemiologia , Prevalência , Ratos , Doenças dos Roedores/epidemiologia , Roedores , Toxoplasma/genética , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/epidemiologiaRESUMO
Background: Outbreaks of contagious ecthyma (CE) are frequently reported in sheep and goat flocks in Nigeria with severe clinical outcomes. CE is a debilitating and economically important disease primarily affecting sheep and goats caused by the Orf virus (ORFV). Despite field reports of CE in the country, there is no concise country-wide epidemiological data on the disease and limited genetic data of circulating Nigerian ORFV are available in the public domain. Aim: An epidemiological survey of CE and molecular characterization of ORFV circulating in Nigeria from 2014 to 2016. Method: Data were collected using designed questionnaires, administered to veterinarians and farmers in selected States of Nigeria. Samples were collected during passive surveillance for CE from 2014 to 2016 which were analyzed by polymerase chain reaction (PCR). The A32L and B2L genes of circulating ORFV were also characterized. Results: Analysis of the questionnaire showed that 69.54% (n = 82/118) of the farmers claimed to have experienced CE in their flocks with average morbidity and mortality rates of 25% and 15%, respectively. A total of 113 veterinarians participated in the study, with 69.9% (n = 79) familiar with CE and claimed CE causes morbidity rates of 25%-37% and mortality rates of 10%-15% in sheep and goats. Laboratory results revealed that ORFV was detected in 72% (18/25) of outbreak samples analyzed by real-time PCR. Phylogenetic analysis of A32L and B2L genes revealed that Nigerian ORFV sequences belong to clusters I and II and are similar to viruses from India, Ethiopia, and China. Conclusions: This study is the first nationwide epidemiological data on the status of CE in sheep and goats in Nigeria. It is also the first report of molecular characterization of two genes of ORFV circulating and causing outbreaks in small ruminants in the country. This study showed that CE is under-reported, widespread and of economic importance to sheep and goat farmers in Nigeria.
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Ectima Contagioso , Doenças das Cabras , Vírus do Orf , Doenças dos Ovinos , Animais , Ectima Contagioso/epidemiologia , Doenças das Cabras/epidemiologia , Cabras , Nigéria/epidemiologia , Vírus do Orf/genética , Filogenia , Ovinos , Doenças dos Ovinos/epidemiologia , Inquéritos e QuestionáriosRESUMO
Background: Salmonella infections continue to be of global concern to poultry health, productivity, and public health. About 44% of the poultry in Nigeria are indigenous and kept in close interaction with farmers who are mostly rural dwellers and have limited access to veterinary and extension services. Aim: The perceptions and practices of farmers of indigenous poultry toward Salmonella infections were assessed to obtain and document baseline data that can be used to create awareness among farmers about these infections and their attendant public health implications. Methods: A cross-sectional approach using a multistage sampling method was used in this survey. A total of 419 farmers keeping indigenous poultry were interviewed using a pre-tested electronic questionnaire in three randomly selected states within North-Central Nigeria. Data were analyzed using descriptive and regression analysis. Results: Out of the 419 respondents, 138 (32.9%), 141 (33.7%), and 140 (33.4%) were from Benue, Kwara, and Plateau States, respectively. Of the 419, 55.4% were females, 40.8% were above 40 years, and 35.8% have over 10 years of farming experience. The majority of the poultry are not housed (58.5%) and farmers predominantly rear chickens (51.8%). Also, 49.9% of the birds were 1-6 months with 41.5% of the flock sizes being 11-20. Respondents had a poor level of perception toward Salmonella infection as the majority did not know that Salmonella affects poultry (89.3%) and that Salmonella infections are zoonotic (94.5%). Significant (p = 0.000) associations existed between categorized perception score and age, educational status, family size, and farming experience of farmers. There were significant (p = 0.000) associations of categorized practice scores with gender, age, education status, family size, and farming experience of farmers. Conclusion: This study has revealed the poor perception of farmers on Salmonella infections and has highlighted their practices. There is a need to raise awareness about these infections to improve indigenous poultry health and productivity as well as public health.
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Aves Domésticas , Infecções por Salmonella , Animais , Galinhas , Fazendeiros , Feminino , Humanos , Masculino , Nigéria/epidemiologiaRESUMO
As pig production increases in Africa, it is essential to identify the pathogens that are circulating in the swine population to assess pig welfare and implement targeted control measures. For this reason, DNA samples collected from pigs in Nigeria in the context of African swine fever monitoring were further screened by PCR for porcine circovirus 2 (PCV-2), porcine circovirus 3 (PCV-3), and porcine parvovirus 1 (PPV1). Forty-seven (45%) pigs were positive for two or more pathogens. Sequence analysis identified PCV-2 genotypes a, b, and d, while limited genetic heterogenicity was observed among PCV-3 strains. All except one of the PPV1 sequences were genetically distinct from those previously identified in other countries.
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Vírus da Febre Suína Africana , Febre Suína Africana , Infecções por Circoviridae , Circovirus , Coinfecção , Parvovirus Suíno , Doenças dos Suínos , Suínos , Animais , Circovirus/genética , Parvovirus Suíno/genética , Vírus da Febre Suína Africana/genética , Doenças dos Suínos/epidemiologia , Coinfecção/epidemiologia , Coinfecção/veterinária , Nigéria/epidemiologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterináriaRESUMO
Livestock trading through live animal markets are potential pathways for the introduction and spread of economically important pathogens like the African swine fever virus (ASFV) to new areas in several countries. Due to the high demand for live pigs in Nigeria both for restocking and slaughter, live pigs are sold at designated live pig markets (LPM) in the country. This involves movement of pigs over long distances. Despite, reports of ASF outbreaks following restocking of pigs bought from LPMs, there is paucity of information on the role of LPMs in the epidemiology of ASF. In this study, data and pig samples (whole blood, sera, tissue) were collected from 4 selected LPMs in Nigeria (Dawaki, Katsit, Numan and Pandam) between 2019 and 2020. Samples were analysed by polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). Four genes of ASFV positive samples were characterized to identify the circulating genotypes. Results revealed trade activities involving transportation of pigs from these selected markets to 42 major cities and towns in thirteen (13) States of Nigeria. PCR results revealed an overall ASF prevalence of 10.77% (66/613). ASFV was confirmed by PCR in all the selected LPMs with a prevalence rate of 3.13%-23.81%. The phylogeny revealed genotype I and serogroup 4 based on the p72 protein that encodes the B646L gene and the EP402R gene encoding the CD2V. While sequence analysis of CVR of B602L gene revealed 8 tetrameric repeats variants, six of which have never been reported in Nigeria. Analysis of sera samples recorded a seroprevalence of 6.9% (16/217) within the study period. Findings from this study show that LPM are hotspots and channels for transmission and continuous spread of ASFV in Nigeria. Therefore, for ASF to be controlled in Nigeria, disease surveillance and regulation at LPMs are critical.
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Vírus da Febre Suína Africana , Febre Suína Africana , Doenças dos Suínos , Vírus da Febre Suína Africana/genética , Animais , Surtos de Doenças/veterinária , Genótipo , Nigéria/epidemiologia , Filogenia , Estudos Soroepidemiológicos , Sus scrofa , Suínos , Doenças dos Suínos/epidemiologiaRESUMO
Antibody-based lateral flow assay (LFA) is a quick and inexpensive tool used to detect pathogens in field samples, especially in hard-to-reach remote areas that may have limited access to central laboratories during an outbreak or surveillance. In this study, we investigated the ability of a commercially available LFA, PenCheck®, to detect African swine fever virus (ASFV) in clinical samples derived from pigs infected with highly virulent ASFV strains. The assay was specific and positively identified the majority of pigs showing high fever during the early stages (between 3 and 5 days) of infection. PenCheck® LFA also detected ASFV in serum and tissue samples collected from pigs that succumbed to experimental ASFV infection and whole blood, plasma, and tissue samples from the field. The limit of detection of the assay was ASFV titer 107.80 TCID50/mL, corresponding to ASFV real-time PCR values below 23 Ct. Although the sensitivity of the assay is less than that of the laboratory-based real-time PCR assays, the results obtained with the PenCheck® LFA in this study suggest that it can be used as a herd-level, field-deployable, and easy-to-use diagnostic tool to identify ASF-affected farms when access to portable molecular assays or central laboratories is not possible.
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Porcine circovirus-2 (PCV-2) is associated with several disease syndromes in domestic pigs that have a significant impact on global pig production and health. Currently, little is known about the status of PCV-2 in Africa. In this study, a total of 408 archived DNA samples collected from pigs in Burkina Faso, Cameroon, Cape Verde, Ethiopia, the Democratic Republic of the Congo, Mozambique, Nigeria, Senegal, Tanzania and Zambia between 2000 and 2018 were screened by PCR for the presence of PCV-2. Positive amplicons of the gene encoding the viral capsid protein (ORF2) were sequenced to determine the genotypes circulating in each country. Four of the nine currently known genotypes of PCV-2 were identified (i.e. PCV-2a, PCV-2b, PCV-2d and PCV-2 g) with more than one genotype being identified in Burkina Faso, Ethiopia, Nigeria, Mozambique, Senegal and Zambia. Additionally, a phylogeographic analysis which included 38 additional ORF2 gene sequences of PCV-2s previously identified in Mozambique, Namibia and South Africa from 2014 to 2016 and 2019 to 2020 and available in public databases, demonstrated the existence of several African-specific clusters and estimated the approximate time of introduction of PCV-2s into Africa from other continents. This is the first in-depth study of PCV-2 in Africa and it has important implications for pig production at both the small-holder and commercial farm level on the continent.
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Infecções por Circoviridae , Circovirus , Doenças dos Suínos , Animais , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/veterinária , Circovirus/genética , DNA Viral/genética , Europa (Continente) , Nigéria , Suínos , Doenças dos Suínos/epidemiologiaRESUMO
Peste des petits ruminants virus (PPRV) is the aetiologic agent of Peste des petits ruminants (PPR), an important viral disease of sheep and goats. PPR is endemic in Nigeria and leads to social and economic losses. The objective of this study was to determine the prevalence of PPR infection and genetically characterize PPRV strains obtained from sheep and goats in three States of Southeast Nigeria. A total of 285 nasal swab samples collected in 20172018 were processed for PPRV genome detection by RTPCR. Sixtyfive (22.81%) of the samples were positive for PPRV. Sequence and phylogenetic analyses revealed that the PPRV belonged to lineages II (11/38, 28.9%) and IV (27/38, 71.1%). The N gene fragment sequence showed a 99.77%100% and 99.98%100% identity among the strains of lineages II and IV, respectively. Fourteen amino acid substitutions, previously unreported in PPRV strains from Nigeria, were recorded. This study confirms the circulation of PPRV lineages II and IV in Southeast Nigeria, the dominance of strains belonging to lineage IV in recent years, and their close genetic relationship with those previously reported in other parts of Nigeria and neighboring countries.
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Doenças das Cabras , Peste dos Pequenos Ruminantes , Vírus da Peste dos Pequenos Ruminantes , Doenças dos Ovinos , Animais , Doenças das Cabras/epidemiologia , Cabras , Nigéria , Peste dos Pequenos Ruminantes/epidemiologia , Vírus da Peste dos Pequenos Ruminantes/genética , Filogenia , Ovinos , Doenças dos Ovinos/epidemiologiaRESUMO
A confirmed African swine fever (ASF) outbreak in Nigeria was further investigated by partial sequencing of the B464L and E183L genes of ASF virus (ASFV). Results revealed the first-time presence of ASFV genotype II in Nigeria and West Africa. This finding has serious implications for control measures and food security.
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Background: Mycoplasma mycoides subsp. mycoides is the causative organism of Contagious Bovine Pleuropneumonia (CBPP). It is a trans-boundary disease and an endemic in Nigeria having caused serious financial loss for the country's economy. Aim: This study was undertaken to isolate and confirm the presence of M. mycoides subsp. mycoides (Mmm) in cattle, from three selected South-Eastern states of Nigeria. Method: A total of 90 bovine samples (25 pleural fluids and 65 lung tissues) suggestive of CBPP were collected from different abattoirs in the three selected South-eastern states of Nigeria (Anambra, Enugu, and Imo), for the isolation of Mmm by employing cultural method, whereas for confirmation polymerase chain reaction (PCR) approach was used. The collected samples were cultured on Pleuropneumonia like organism (PPLO) agar according to specific protocols. Results: Twenty five of the samples (lungs and pleural fluid) were positive for Mmm on PPLO agar giving an isolation rate of 27.7%. Only 21 of the isolates were further confirmed using PCR. The PCR amplification of the isolates produced a product of 1.1 kbp which is specific for Mmm. No positive isolates were recovered from Imo state. Conclusion: This study confirms the presence of Mmm as the causative organism of CBPP in Southeast Nigeria. It is recommended that active surveillance and vaccination protocol should be undertaken in the region for the control and prevention of this disease.