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1.
Artigo em Inglês | MEDLINE | ID: mdl-38982627

RESUMO

AIMS: Coxiella burnetii is a highly infectious organism that is easily spread through aerosols causing Q fever in humans. Ticks can harbour and transmit C. burnetii to animals, contributing to disease maintenance. Our aim was to examine the presence of C. burnetii in ticks in Uganda. METHODS AND RESULTS: In this study, ticks were collected from five Ugandan districts and tested by real-time PCR for C. burnetii (Coxiella outer membrane protein 1 gene). A total of 859 tick pools (9602 individual ticks) were tested, and pool positivity for C. burnetii was 5.5% (n = 47). Pooled prevalence differed by district; the highest was Luwero (7.3%), then Gulu (6.6%), and Kasese had the lowest (1.3%). However, district variation was not statistically significant (Fisher's exact = 0.07). Ticks collected from dogs and cats had the highest positivity rates [23/47, (48.9%)] followed by livestock (cattle, goats, sheep, and pigs) [18/47, (38.3%)] and vegetation [6/47, (12.8%)]. Haemaphysalis elliptica had the highest infection rates, followed by Rhipicephalus appendiculatus, Amblyomma variegatum and Rhipicephalus decoloratus had similar prevalence. CONCLUSIONS: Although ticks are not the primary transmitters of C. burnetii to humans, pathogen detection in ticks can be an indirect indicator of risk among animal hosts. Vulnerable populations, including occupations with close animal contact such as farming, butchery, and veterinary practice, have an increased risk of C. burnetii exposure. Veterinarians and clinicians should be aware that C. burnetii may cause human and animal illness in these regions.

2.
Microbiol Resour Announc ; 13(1): e0081723, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38078696

RESUMO

Staphylococcus urealyticus bacteria are pathogenic among immune-compromised individuals. A strain (MUWRP0921) of Staphylococcus urealyticus with a genome of 2,708,354 bp was isolated from Uganda and carries genes that are associated with antibiotic resistance, including resistance to macrolides (erm(C) and mph(C')), aminoglycosides (aac(6")-aph(2")), tetracyclines (tet(K)), and trimethoprim (dfrG).

3.
Pathogens ; 12(11)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38003798

RESUMO

Klebsiella pneumoniae is a threat to public health due to its continued evolution. In this study, we investigated the evolution, convergence, and transmission of hypervirulent and multi-drug resistant (MDR) clones of K. pneumoniae within healthcare facilities in Uganda. There was high resistance to piperacillin (90.91%), cefuroxime (86.96%), ceftazidime (84.62%), cefotaxime (84.00%), amoxicillin/clavulanate (75%), nalidixic acid (73.68%), and nitrofurantoin (71.43%) antibiotics among K. pneumoniae isolates. The isolates were genetically diverse, consisting of 20 different sequence types (STs) and 34 K-serotype groups. Chromosomal fosA (for fosfomycin) and oqxAB efflux pump genes were detected in all isolates. Two carbapenem resistance genes, blaNDM-5 and blaOXA-181 plus extended-spectrum beta-lactamase (blaCTX-M-15) gene (68.12%), quinolone-resistant genes qnrS1 (28.99%), qnrB1 (13.04%), and qnrB6 (13.04%) and others were found. All, except three of the isolates, harbored plasmids. While the isolates carried a repertoire of virulence genes, only two isolates carried hypervirulent genes demonstrating a low prevalence (2.90%) of hypervirulent strains. Our study demonstrated genetically diverse populations of K. pneumoniae, low levels of carbapenem resistance among the isolates, and no convergence of MDR and hypervirulence. Emerging high-risk international pandemic clones (ST11, ST14, ST147, ST 86 and ST307) were detected in these healthcare settings which are difficult to treat.

4.
PLoS One ; 18(11): e0294424, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37992119

RESUMO

Multi-drug resistant (MDR) globally disseminated extraintestinal pathogenic high-risk Escherichia coli (ExPEC) clones are threatening the gains in bacterial disease management. In this study, we evaluated the genomic structure including the resistome and virulome of the E. coli isolates from extraintestinal infections using whole genome sequencing (WGS). The results highlight that isolates were highly resistant (≥ 90.0%) to commonly used antibiotics (Ampicillin, Trimethoprim-Sulfamethoxazole, Nalidixic acid, and Piperacillin) and were less (<14%) resistant to last resort antibiotics; Imipenem (10.94%) and Meropenem (10.20%). A greater proportion of the E. coli isolates belonged to phylogroup B2 (30.52%) and phylogroup A (27.37%). The sequence types ST131 of phylogroup B2 (21.05%) and ST648 of phylogroup F (9.3%) were the dominant pandemic high-risk clones identified in addition to the ST1193, ST410, ST69, ST38, ST405, and ST10. Many of the isolates were MDR and most (64.58%) carried the blaCTX-M-15 gene for extended-spectrum ß-lactamases. There was a high correlation between phylogroups and the occurrence of both antimicrobial resistance and virulence genes. The cephalosporin-resistance gene blaEC-5 was only found in phylogroup B2 while blaEC-8 and blaEC-19, were only found within phylogroup D and phylogroup F respectively. Aminoglycoside gene (aadA1) was only associated with phylogroups D and C. The isolates were armed with a broad range of virulence genes including adhesins, toxins, secreted proteases, iron uptake genes, and others. The yfcv, chuA, and kpsE genes preferentially occurred among isolates of phylogroup B2. The study underlines the predominance of MDR internationally disseminated high-risk ExPEC clones with a broad range of virulence genes known to be highly transmissible in healthcare and community settings.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli Extraintestinal Patogênica , Humanos , Escherichia coli , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Atenção Terciária à Saúde , Uganda , Pandemias , Genótipo , Antibacterianos/farmacologia , Fatores de Virulência/genética , beta-Lactamases/genética , Proteínas de Membrana Transportadoras/genética , Proteínas de Escherichia coli/genética
5.
Microorganisms ; 11(8)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37630428

RESUMO

Commensal Escherichia coli with broad repertoire of virulence and antimicrobial resistance (AMR) genes pose serious public health risks as reservoirs of AMR and virulence. This study undertook whole genome characterization of commensal E. coli from food-producing animals in Uganda to investigate their genome variability (resistome and virulome). We established that the E. coli had high genomic diversity with 38 sequence types, 24 FimH types, and 33 O-antigen serotypes randomly distributed within three phylogroups (A, B1, and E). A greater proportion (≥93.65%) of the E. coli were resistant to amoxicillin/clavulanate and ampicillin antibiotics. The isolates were AmpC beta-lactamase producers dominated by blaEC-15 (71.88%) and tet(A) (20.31%) antimicrobial resistant genes besides a diverse armory of virulence-associated genes in the class of exotoxin, adhesins, iron uptake, and serine protease autotransporters which varied by host species. Cattle were found to be the major source of E. coli carrying Shiga toxin genes, whereas swine was the main source of E. coli carrying colicin-like Usp toxin gene. The study underscores the importance of livestock as the carrier of E. coli with antimicrobial resistance and a large repertoire of virulence traits with a potential of causing disease in animals and humans by acquiring more genetic traits.

6.
PLoS Negl Trop Dis ; 17(7): e0011273, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37498943

RESUMO

Rickettsia microorganisms are causative agents of several neglected emerging infectious diseases in humans transmitted by arthropods including ticks. In this study, ticks were collected from four geographical regions of Uganda and pooled in sizes of 1-179 ticks based on location, tick species, life stage, host, and time of collection. Then, they were tested by real-time PCR for Rickettsia species with primers targeting gltA, 17kDa and ompA genes, followed by Sanger sequencing of the 17kDa and ompA genes. Of the 471 tick pools tested, 116 (24.6%) were positive for Rickettsia spp. by the gltA primers. The prevalence of Rickettsia varied by district with Gulu recording the highest (30.1%) followed by Luwero (28.1%) and Kasese had the lowest (14%). Tick pools from livestock (cattle, goats, sheep, and pigs) had the highest positivity rate, 26.9%, followed by vegetation, 23.1%, and pets (dogs and cats), 19.7%. Of 116 gltA-positive tick pools, 86 pools were positive using 17kDa primers of which 48 purified PCR products were successfully sequenced. The predominant Rickettsia spp. identified was R. africae (n = 15) in four tick species, followed by R. conorii (n = 5) in three tick species (Haemaphysalis elliptica, Rhipicephalus appendiculatus, and Rh. decoloratus). Rickettsia conorii subsp. israelensis was detected in one tick pool. These findings indicate that multiple Rickettsia spp. capable of causing human illness are circulating in the four diverse geographical regions of Uganda including new strains previously known to occur in the Mediterranean region. Physicians should be informed about Rickettsia spp. as potential causes of acute febrile illnesses in these regions. Continued and expanded surveillance is essential to further identify and locate potential hotspots with Rickettsia spp. of concern.


Assuntos
Doenças do Gato , Doenças do Cão , Ixodidae , Rhipicephalus , Rickettsia , Rickettsiose do Grupo da Febre Maculosa , Animais , Bovinos , Humanos , Cães , Ovinos , Gatos , Suínos , Uganda/epidemiologia , Israel , Rickettsia/genética , Ixodidae/microbiologia , Rickettsiose do Grupo da Febre Maculosa/epidemiologia , Rhipicephalus/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Cabras
7.
BMC Infect Dis ; 23(1): 435, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37370005

RESUMO

Human adenoviruses (HAdV) are a diverse group of viruses causing a broad range of infections of the respiratory, urogenital and gastrointestinal tracts and keratoconjunctivitis. There are seven species of human adenoviruses with 113 genotypes which may contain multiple genetic variants. This study characterised respiratory human adenoviruses and associated factors in samples collected from selected hospitals in Uganda. A total of 2,298 nasopharyngeal samples were collected between the period of 2008 to 2016 from patients seeking health care at tertiary hospitals for influenza-like illness. They were screened by polymerase chain reaction (PCR) to determine the prevalence of HAdV. HAdV was cultured in A549 cell lines and the hexon gene was sequenced for genotyping. Of the 2,298 samples tested, 225 (9.8%) were adenovirus-positive by PCR. Age was found to be significantly associated with HAdV infections (p = 0.028) with 98% (220/225) of the positives in children aged 5 years and below and none in adults above 25 years of age. The sequenced isolates belonged to species HAdV-B and HAdV-C with most isolates identified as genotype B3. The results showed a high prevalence and genetic diversity in respiratory HAdV circulating in Ugandan population. Deeper genomic characterization based on whole genome sequencing may be necessary to further elucidate possible transmission and impact of current adenovirus-vectored vaccines in Africa.


Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos , Infecções Respiratórias , Criança , Adulto , Humanos , Lactente , Uganda/epidemiologia , Análise de Sequência de DNA , Infecções por Adenovirus Humanos/epidemiologia , Infecções Respiratórias/epidemiologia , Genótipo , Filogenia
8.
Microbiol Resour Announc ; 12(4): e0084022, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-36877041

RESUMO

We report a genome sequence of Wohlfahrtiimonas chitiniclastica strain MUWRP0946, isolated from a hospitalized patient in Uganda. The genome size was 2.08 million bases, and the genome completeness was 94.22%. The strain carries tetracycline, folate pathway antagonist, ß-lactam, and aminoglycoside antibiotic resistance genes.

9.
Viruses ; 14(9)2022 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-36146881

RESUMO

A (H9N2) avian influenza A viruses were first detected in Uganda in 2017 and have since established themselves in live bird markets. The aim of this study was to establish the subsequent genetic evolution of H9N2 viruses in Uganda. Cloacal samples collected from live bird market stalls in Kampala from 2017 to 2019 were screened by RT-PCR for influenza A virus and H9N2 viruses were isolated in embryonated eggs. One hundred and fifty H9N2 isolates were subjected to whole genome sequencing on the Illumina MiSeq platform. The sequence data analysis and comparison with contemporary isolates revealed that the virus was first introduced into Uganda in 2014 from ancestors in the Middle East. There has since been an increase in nucleotide substitutions and reassortments among the viruses within and between live bird markets, leading to variations in phylogeny of the different segments, although overall diversity remained low. The isolates had several mutations such as HA-Q226L and NS-I106M that enable mammalian host adaptation, NP-M105V, PB1-D3V, and M1-T215A known for increased virulence/pathogenicity and replication, and PA-E199D, NS-P42S, and M2-S31N that promote drug resistance. The PA-E199D substitution in particular confers resistance to the endonuclease inhibitor Baloxavir acid, which is one of the new anti-influenza drugs. Higher EC50 was observed in isolates with a double F105L+E199D substitution that may suggest a possible synergistic effect. These H9N2 viruses have established an endemic situation in live bird markets in Uganda because of poor biosecurity practices and therefore pose a zoonotic threat. Regular surveillance is necessary to further generate the needed evidence for effective control strategies and to minimize the threats.


Assuntos
Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Influenza Humana , Animais , Dibenzotiepinas , Endonucleases/genética , Evolução Molecular , Adaptação ao Hospedeiro , Humanos , Influenza Aviária/epidemiologia , Mamíferos , Morfolinas , Nucleotídeos , Filogenia , Aves Domésticas , Piridonas , Triazinas , Uganda/epidemiologia , Virulência/genética
10.
Viruses ; 13(9)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34578330

RESUMO

Influenza D virus (IDV) was first isolated in 2011 in Oklahoma, USA from pigs presenting with influenza-like symptoms. IDV is known to mainly circulate in ruminants, especially cattle. In Africa, there is limited information on the epidemiology of IDV, although the virus has likely circulated in the region since 2012. In the present study, we investigated the seropositivity of IDV among domestic ruminants and swine in West and East Africa from 2017 to 2020. Serum samples were analyzed using the hemagglutination inhibition (HI) assay. Our study demonstrated that IDV is still circulating in Africa, with variations in seropositivity among countries and species. The highest seropositivity was detected in cattle (3.9 to 20.9%). Our data highlights a need for extensive surveillance of IDV in Africa in order to better understand the epidemiology of the virus in the region.


Assuntos
Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/imunologia , Ruminantes/imunologia , Ruminantes/virologia , Thogotovirus/imunologia , Thogotovirus/patogenicidade , África Oriental/epidemiologia , África Ocidental/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/virologia , Feminino , Masculino , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia
11.
BMC Infect Dis ; 21(1): 585, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34134656

RESUMO

BACKGROUND: Human coronaviruses are causative agents of respiratory infections with several subtypes being prevalent worldwide. They cause respiratory illnesses of varying severity and have been described to be continuously emerging but their prevalence is not well documented in Uganda. This study assessed the seroprevalence of antibodies against the previously known human coronaviruses prior 2019 in Uganda. METHODS: A total 377 serum samples collected from volunteers that showed influenza like illness in five hospital-based sentinel sites and archived were analyzed using a commercial Qualitative Human Coronavirus Antibody IgG ELISA kit. Although there is no single kit available that can detect the presence of all the circulating coronaviruses, this kit uses a nucleoprotein, aa 340-390 to coat the wells and since there is significant homology among the various human coronavirus strains with regards to the coded for proteins, there is significant cross reactivity beyond HCoV HKU-39849 2003. This gives the kit a qualitative ability to detect the presence of human coronavirus antibodies in a sample. RESULTS: The overall seroprevalence for all the sites was 87.53% with no significant difference in the seroprevalence between the Hospital based sentinel sites (p = 0.8). Of the seropositive, the age group 1-5 years had the highest percentage (46.97), followed by 6-10 years (16.67) and then above 20 (16.36). An odds ratio of 1.6 (CI 0.863-2.97, p = 0.136) showed that those volunteers below 5 years of age were more likely to be seropositive compared to those above 5 years. The seropositivity was generally high throughout the year with highest being recorded in March and the lowest in February and December. CONCLUSIONS: The seroprevalence of Human coronaviruses is alarmingly high which calls for need to identify and characterize the circulating coronavirus strains so as to guide policy on the control strategies.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Coronavirus/epidemiologia , Coronavirus , Imunoglobulina G/sangue , Adolescente , Adulto , Criança , Pré-Escolar , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Feminino , Hospitais , Humanos , Lactente , Masculino , Vigilância de Evento Sentinela , Estudos Soroepidemiológicos , Uganda/epidemiologia , Adulto Jovem
12.
Viruses ; 13(4)2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918166

RESUMO

Genetic analysis of circulating avian influenza viruses (AIVs) in wild birds at different geographical regions during the same period could improve our knowledge about virus transmission dynamics in natural hosts, virus evolution as well as zoonotic potential. Here, we report the genetic and molecular characterization of H6N2 influenza viruses isolated from migratory birds in Turkey, Egypt, and Uganda during 2017-2018. The Egyptian and Turkish isolates were genetically closer to each other than they were to the virus isolated from Uganda. Our results also suggest that multiple reassortment events were involved in the genesis of the isolated viruses. All viruses contained molecular markers previously associated with increased replication and/or pathogenicity in mammals. The results of this study indicate that H6N2 viruses carried by migratory birds on the West Asian/East African and Mediterranean/Black Sea flyways have the potential to transmit to mammals including humans. Additionally, adaptation markers in these viruses indicate the potential risk for poultry, which also increases the possibility of human exposure to these viruses.


Assuntos
Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Aviária/virologia , Filogenia , Vírus Reordenados/genética , Migração Animal , Animais , Animais Selvagens/virologia , Galinhas/virologia , Egito , Genoma Viral , Humanos , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/transmissão , Aves Domésticas/virologia , Turquia , Uganda
13.
Emerg Microbes Infect ; 10(1): 753-761, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33754959

RESUMO

Sub-Saharan Africa was historically considered an animal influenza cold spot, with only sporadic highly pathogenic H5 outbreaks detected over the last 20 years. However, in 2017, low pathogenic avian influenza A(H9N2) viruses were detected in poultry in Sub-Saharan Africa. Molecular, phylogenetic, and antigenic characterization of isolates from Benin, Togo, and Uganda showed that they belonged to the G1 lineage. Isolates from Benin and Togo clustered with viruses previously described in Western Africa, whereas viruses from Uganda were genetically distant and clustered with viruses from the Middle East. Viruses from Benin exhibited decreased cross-reactivity with those from Togo and Uganda, suggesting antigenic drift associated with reduced replication in Calu-3 cells. The viruses exhibited mammalian adaptation markers similar to those of the human strain A/Senegal/0243/2019 (H9N2). Therefore, viral genetic and antigenic surveillance in Africa is of paramount importance to detect further evolution or emergence of new zoonotic strains.


Assuntos
Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/imunologia , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , África Subsaariana , Animais , Anticorpos Antivirais/imunologia , Variação Antigênica , Galinhas/virologia , Reações Cruzadas , Evolução Molecular , Humanos , Vírus da Influenza A Subtipo H9N2/patogenicidade , Vírus da Influenza A Subtipo H9N2/fisiologia , Influenza Humana/virologia , Filogenia , Virulência , Replicação Viral
14.
PLoS One ; 15(5): e0232343, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32384098

RESUMO

BACKGROUND: Drug susceptibility testing for Mycobacterium tuberculosis (MTB) is difficult to perform in resource-limited settings where Acid Fast Bacilli (AFB) smears are commonly used for disease diagnosis and monitoring. We developed a simple method for extraction of MTB DNA from AFB smears for sequencing-based detection of mutations associated with resistance to all first and several second-line anti-tuberculosis drugs. METHODS: We isolated MTB DNA by boiling smear content in a Chelex solution, followed by column purification. We sequenced PCR-amplified segments of the rpoB, katG, embB, gyrA, gyrB, rpsL, and rrs genes, the inhA, eis, and pncA promoters and the entire pncA gene. RESULTS: We tested our assay on 1,208 clinically obtained AFB smears from Ghana (n = 379), Kenya (n = 517), Uganda (n = 262), and Zambia (n = 50). Coverage depth varied by target and slide smear grade, ranging from 300X to 12000X on average. Coverage of ≥20X was obtained for all targets in 870 (72%) slides overall. Mono-resistance (5.9%), multi-drug resistance (1.8%), and poly-resistance (2.4%) mutation profiles were detected in 10% of slides overall, and in over 32% of retreatment and follow-up cases. CONCLUSION: This rapid AFB smear DNA-based method for determining drug resistance may be useful for the diagnosis and surveillance of drug-resistant tuberculosis.


Assuntos
DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Humanos
15.
PLoS One ; 11(10): e0164861, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27755572

RESUMO

INTRODUCTION: Influenza surveillance was conducted in Uganda from October 2008 to December 2014 to identify and understand the epidemiology of circulating influenza strains in out-patient clinic attendees with influenza-like illness and inform control strategies. METHODOLOGY: Surveillance was conducted at five hospital-based sentinel sites. Nasopharyngeal and/or oropharyngeal samples, epidemiological and clinical data were collected from enrolled patients. Real-time reverse transcription polymerase chain reaction (RT-PCR) was performed to identify and subtype influenza strains. Data were double-entered into an Epi Info 3.5.3 database and exported to STATA 13.0 software for analysis. RESULTS: Of the 6,628 patient samples tested, influenza virus infection was detected in 10.4% (n = 687/6,628) of the specimens. Several trends were observed: influenza circulates throughout the year with two peaks; the major one from September to November and a minor one from March to June. The predominant strains of influenza varied over the years: Seasonal Influenza A(H3) virus was predominant from 2008 to 2009 and from 2012 to 2014; Influenza A(H1N1)pdm01 was dominant in 2010; and Influenza B virus was dominant in 2011. The peaks generally coincided with times of higher humidity, lower temperature, and higher rainfall. CONCLUSION: Influenza circulated throughout the year in Uganda with two major peaks of outbreaks with similar strains circulating elsewhere in the region. Data on the circulating strains of influenza and its patterns of occurrence provided critical insights to informing the design and timing of influenza vaccines for influenza prevention in tropical regions of sub-Saharan Africa.


Assuntos
Influenza Humana/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Umidade , Lactente , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza B/genética , Vírus da Influenza B/isolamento & purificação , Influenza Humana/virologia , Masculino , Nasofaringe/virologia , Orofaringe/virologia , Prevalência , RNA Viral/metabolismo , Chuva , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano , Temperatura , Uganda/epidemiologia
16.
Influenza Other Respir Viruses ; 10(6): 486-492, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27339410

RESUMO

We report a whole-genome analysis of 19 influenza A(H1N1)pdm09 isolates from four Ugandan hospitals between 2009 and 2011. The isolates differed from the vaccine strain A/California/07/2009 by three amino acid substitutions P100S, S220T, and I338V in the hemagglutinin and by two amino acid substitutions V106I and N248D in the neuraminidase proteins with consistent mutations in all gene segments distinguishing isolates from the 2009/2010 to 2010/2011 seasons. Phylogenetic analysis showed low genetic evolution, with genetic distances of 0%-1.3% and 0.1%-1.6% for HA and NA genes, respectively. The amino acid substitutions did not lead to antigenic differences from the reference strains.


Assuntos
Genoma Viral , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/virologia , Substituição de Aminoácidos , Antígenos Virais , Evolução Molecular , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Neuraminidase/química , Neuraminidase/genética , Filogenia , RNA Viral/genética , Estações do Ano , Análise de Sequência de RNA , Uganda/epidemiologia
17.
BMC Vet Res ; 10: 50, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24576325

RESUMO

BACKGROUND: Avian influenza viruses may cause severe disease in a variety of domestic animal species worldwide, with high mortality in chickens and turkeys. To reduce the information gap about prevalence of these viruses in animals in Uganda, this study was undertaken. RESULTS: Influenza A virus prevalence by RT-PCR was 1.1% (45/4,052) while seroprevalence by ELISA was 0.8% (24/2,970). Virus prevalence was highest in domestic ducks (2.7%, 17/629) and turkeys (2.6%, 2/76), followed by free-living waterfowl (1.3%, 12/929) and swine (1.4%, 7/511). A lower proportion of chicken samples (0.4%, 7/1,865) tested positive. No influenza A virus was isolated. A seasonal prevalence of these viruses in waterfowl was 0.7% (4/561) for the dry and 2.2% (8/368) for the wet season. In poultry, prevalence was 0.2% (2/863) for the dry and 1.4% (24/1,713) for the wet season, while that of swine was 0.0% (0/159) and 2.0% (7/352) in the two seasons, respectively. Of the 45 RT-PCR positive samples, 13 (28.9%) of them were H5 but none was H7. The 19 swine sera positive for influenza antibodies by ELISA were positive for H1 antibodies by HAI assay, but the subtype(s) of ELISA positive poultry sera could not be determined. Antibodies in the poultry sera could have been those against subtypes not included in the HAI test panel. CONCLUSIONS: The study has demonstrated occurrence of influenza A viruses in animals in Uganda. The results suggest that increase in volumes of migratory waterfowl in the country could be associated with increased prevalence of these viruses in free-living waterfowl and poultry.


Assuntos
Animais Selvagens , Anseriformes , Vírus da Influenza A/isolamento & purificação , Gado , Animais , Feminino , Modelos Logísticos , Masculino , Razão de Chances , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/veterinária , Infecções por Orthomyxoviridae/virologia , Fatores de Risco , Estudos Soroepidemiológicos , Uganda/epidemiologia
18.
Virol J ; 10: 11, 2013 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-23289789

RESUMO

BACKGROUND: Influenza B viruses can cause morbidity and mortality in humans but due to the lack of an animal reservoir are not associated with pandemics. Because of this, there is relatively limited genetic sequences available for influenza B viruses, especially from developing countries. Complete genome analysis of one influenza B virus and several gene segments of other influenza B viruses isolated from Uganda from May 2009 through December 2010 was therefore undertaken in this study. METHODS: Samples were collected from patients showing influenza like illness and screened for influenza A and B by PCR. Influenza B viruses were isolated on Madin-Darby Canine Kidney cells and selected isolates were subsequently sequenced and analyzed phylogenetically. FINDINGS: Of the 2,089 samples collected during the period, 292 were positive by PCR for influenza A or B; 12.3% of the PCR positives were influenza B. Thirty influenza B viruses were recovered and of these 25 that grew well consistently on subculture were subjected to further analysis. All the isolates belonged to the B/Victoria-lineage as identified by hemagglutination inhibition assay and genetic analysis except one isolate that grouped with the B-Yamagata-lineage. The Ugandan B/Victoria-lineage isolates grouped in clade 1 which was defined by the N75K, N165K and S172P substitutions in hemagglutinin (HA) protein clustered together with the B/Brisbane/60/2008 vaccine strain. The Yamagata-like Ugandan strain, B/Uganda/MUWRP-053/2009, clustered with clade 3 Yamagata viruses such as B/Bangladesh/3333/2007 which is characterized by S150I and N166Y substitutions in HA. CONCLUSION: In general there was limited variation among the Ugandan isolates but they were interestingly closer to viruses from West and North Africa than from neighboring Kenya. Our isolates closely matched the World Health Organization recommended vaccines for the seasons.


Assuntos
Vírus da Influenza B/classificação , Vírus da Influenza B/genética , Influenza Humana/epidemiologia , Análise de Sequência de DNA , Adolescente , Linhagem Celular , Criança , Pré-Escolar , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Lactente , Vírus da Influenza B/isolamento & purificação , Influenza Humana/virologia , Rim/virologia , Epidemiologia Molecular , Dados de Sequência Molecular , Neuraminidase/genética , Filogenia , Reação em Cadeia da Polimerase , Estações do Ano , Uganda/epidemiologia , Adulto Jovem
19.
PLoS One ; 6(11): e27803, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22132146

RESUMO

The increasing availability of complete influenza virus genomes is deepening our understanding of influenza evolutionary dynamics and facilitating the selection of vaccine strains. However, only one complete African influenza virus sequence is available in the public domain. Here we present a complete genome analysis of 59 influenza A/H3N2 viruses isolated from humans in Uganda during the 2008 and 2009 season. Isolates were recovered from hospital-based sentinel surveillance for influenza-like illnesses and their whole genome sequenced. The viruses circulating during these two seasons clearly differed from each other phylogenetically. They showed a slow evolution away from the 2009/10 recommended vaccine strain (A/Brisbane/10/07), instead clustering with the 2010/11 recommended vaccine strain (A/Perth/16/09) in the A/Victoria/208/09 clade, as observed in other global regions. All of the isolates carried the adamantane resistance marker S31N in the M2 gene and carried several markers of enhanced transmission; as expected, none carried any marker of neuraminidase inhibitor resistance. The hemagglutinin gene of the 2009 isolates differed from that of the 2008 isolates in antigenic sites A, B, D, and to a lesser extent, C and E indicating evidence of an early phylogenetic shift from the 2008 to 2009 viruses. The internal genes of the 2009 isolates were similar to those of one 2008 isolate, A/Uganda/MUWRP-050/2008. Another 2008 isolate had a truncated PB1-F2 protein. Whole genome sequencing can enhance surveillance of future seasonal changes in the viral genome which is crucial to ensure that selected vaccine strains are protective against the strains circulating in Eastern Africa. This data provides an important baseline for this surveillance. Overall the influenza virus activity in Uganda appears to mirror that observed in other regions of the southern hemisphere.


Assuntos
Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/epidemiologia , Influenza Humana/virologia , Adolescente , Adulto , Criança , Pré-Escolar , Genes Virais/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Uganda/epidemiologia , Adulto Jovem
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