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1.
PLoS One ; 17(9): e0271321, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36149889

RESUMO

Recent reports of haemagglutinin antigen (HA) mismatch between vaccine composition strains and circulating strains, have led to renewed interest in influenza B viruses. Additionally, there are concerns about resistance to neuraminidase inhibitors in new influenza B isolates. To assess the potential impact in Ghana, we characterized the lineages of influenza B viruses that circulated in Ghana between 2016 and 2017 from different regions of the country: Southern, Northern and Central Ghana. Eight representative specimens from the three regions that were positive for influenza B virus by real-time RT-PCR were sequenced and compared to reference genomes from each lineage. A total of eleven amino acids substitutions were detected in the B/Victoria lineage and six in the B/Yamagata lineage. The strains of influenza B viruses were closely related to influenza B/Brisbane/60/2008 and influenza B/Phuket/3073/2013 for the Victoria and Yamagata lineages, respectively. Three main amino acid substitutions (P31S, I117V and R151K) were found in B/Victoria lineages circulating between 2016 and 2017, while one strain of B/Victoria possessed a unique glycosylation site at amino acid position 51 in the HA2 subunit. Two main substitutions (L172Q and M251V) were detected in the HA gene of the B/Yamagata lineage. The U.S. CDC recently reported a deletion sub-group in influenza B virus, but this was not identified among the Ghanaian specimens. Close monitoring of the patterns of influenza B evolution is necessary for the efficient selection of representative viruses for the design and formulation of effective influenza vaccines.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza , Vírus da Influenza B , Influenza Humana , Aminoácidos/genética , Gana/epidemiologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza B/genética , Influenza Humana/virologia , Neuraminidase/genética , Filogenia
2.
Sci Rep ; 9(1): 8621, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197225

RESUMO

The current global malaria control and elimination agenda requires development of additional effective disease intervention tools. Discovery and characterization of relevant parasite antigens is important for the development of new diagnostics and transmission monitoring tools and for subunit vaccine development. This study assessed the natural antibody response profile of seven novel Plasmodium falciparum pre-erythrocytic antigens and their potential association with protection against clinical malaria. Antigen-specific antibody levels in plasma collected at six time points from a longitudinal cohort of one-to-five year old children resident in a seasonal malaria transmission area of northern Ghana were assessed by ELISA. Antibody levels were compared between parasite-positive and parasite-negative individuals and the association of antibody levels with malaria risk assessed using a regression model. Plasma antibody levels against five of the seven antigens were significantly higher in parasite-positive children compared to parasite-negative children, especially during low transmission periods. None of the antigen-specific antibodies showed an association with protection against clinical malaria. The study identified five of the seven antigens as markers of exposure to malaria, and these will have relevance for the development of disease diagnostic and monitoring tools. The vaccine potential of these antigens requires further assessment.


Assuntos
Antígenos de Protozoários/imunologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Plasmodium falciparum/imunologia , Anticorpos Antiprotozoários/imunologia , Pré-Escolar , Estudos de Coortes , Epitopos/imunologia , Gana , Humanos , Lactente , Modelos Lineares , Estudos Longitudinais , Parasitemia/imunologia , Parasitemia/parasitologia
3.
Diagn Microbiol Infect Dis ; 60(3): 323-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18031968

RESUMO

A previously unknown Leishmania spp., inferred by DNA sequence analysis of the small subunit ribosomal RNA gene and the internal transcribed spacer region (ITS1), was detected in tissue biopsies from patients living in the Eastern Ghanaian community of Taviefe. Restriction fragment length polymorphism analysis of the ITS1 amplicon supports the possibility of an uncharacterized Leishmania spp.


Assuntos
Surtos de Doenças , Leishmania/classificação , Leishmania/isolamento & purificação , Leishmaniose/epidemiologia , Leishmaniose/parasitologia , Animais , DNA Intergênico/química , DNA Intergênico/genética , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Gana/epidemiologia , Humanos , Filogenia , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 18S/genética , Homologia de Sequência do Ácido Nucleico
4.
Influenza Other Respir Viruses ; 10(5): 367-74, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27239956

RESUMO

BACKGROUND: Influenza epidemiology in Africa is generally not well understood. Using syndrome definitions to screen patients for laboratory confirmation of infection is an established means to effectively conduct influenza surveillance. METHODS: To compare influenza-related epidemiologic data, from October 2010 through March 2013, we enrolled hospitalized severe acute respiratory infection (SARI; fever with respiratory symptoms) and acute febrile illness (AFI; fever without respiratory or other localizing symptoms) patients from three referral hospitals in Ghana. Demographic and epidemiologic data were obtained from enrolled patients after which nasopharyngeal and oropharyngeal swabs were collected, and processed by molecular methods for the presence of influenza viruses. RESULTS: Of 730 SARI patients, 59 (8%) were influenza positive; of 543 AFI patients, 34 (6%) were positive for influenza. Both SARI and AFI surveillance yielded influenza A(H3N2) (3% versus 1%), A(H1N1)pdm09 (2% versus 1%), and influenza B (3% versus 4%) in similar proportions. Data from both syndromes show year-round influenza transmission but with increased caseloads associated with the rainy seasons. CONCLUSIONS: As an appreciable percentage of influenza cases (37%) presented without defined respiratory symptoms, and thus met the AFI but not the SARI definition, it is important to consider broader screening criteria (i.e., AFI) to identify all laboratory-confirmed influenza. The identified influenza transmission seasonality has important implications for the timing of related public health interventions.


Assuntos
Hospitalização/estatística & dados numéricos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/epidemiologia , Pacientes Internados , Infecções Respiratórias/epidemiologia , Vigilância de Evento Sentinela , Doença Aguda/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Febre , Gana/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Infecções Respiratórias/virologia , Adulto Jovem
5.
Mil Med ; 180(1): 17-22, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25562852

RESUMO

OBJECTIVES: We face the specter of global transmission of highly resistant Neisseria gonorrhoeae. The U.S. Department of Defense's Armed Forces Health Surveillance Center has engaged many military and civilian partners (including Ghana) in a sexually transmitted infections (STI) program to address emerging needs in STI surveillance. We implemented gonorrhea surveillance in Ghana to fill the gap in knowledge regarding gonorrhea prevalence and antimicrobial resistance characterization in Ghana. METHODS: Gonorrhea surveillance was conducted from June 2012 to March 2013 as one of the AFHSC surveillance network partners at two Ghana Armed Forces (GAF) military clinics. The population encompassed a convenience sampling of patients presenting with STI symptoms. Urine was taken for nucleic acid amplification testing (NAAT). A urethral or cervical/vaginal specimen was obtained for culture and antibiotic susceptibility testing. RESULTS: 13/220 (6%) specimens tested were positive by culture (7 of which were confirmed); and 39/213 (18%) specimens tested were positive by NAAT. Positive results were biased toward men. Cultures were resistant to ciprofloxacin, penicillin and tetracycline and sensitive to cephalosporins. CONCLUSION: This investigation provides data on gonorrhea prevalence and resistance profiles in Ghana hitherto poorly characterized. We note significant resistance to fluoroquinolones without the presence of resistance yet to the cephalosporins.


Assuntos
Antibacterianos/farmacologia , Gonorreia/epidemiologia , Gonorreia/microbiologia , Neisseria gonorrhoeae/efeitos dos fármacos , Ambulatório Hospitalar , Vigilância da População , Adolescente , Adulto , Farmacorresistência Bacteriana Múltipla , Feminino , Gana/epidemiologia , Hospitais Militares , Humanos , Masculino , Pessoa de Meia-Idade , Neisseria gonorrhoeae/isolamento & purificação , Prevalência , Adulto Jovem
6.
Int J Parasitol ; 45(11): 679-84, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26099650

RESUMO

An active case detection approach with PCR diagnosis was used in the Ho District of the Volta Region, Ghana that identified individuals with active cutaneous leishmaniasis. Three isolates were successfully cultured and DNA sequences from these were analysed (ribosomal RNA internal transcribed spacer 1; ribosomal protein L23a intergenic spacer; RNA polymerase II large subunit), showing them to be Leishmania, identical to each other but different from all other known Leishmania spp. Phylogenetic analysis showed the parasites to be new members of the Leishmania enriettii complex, which is emerging as a possible new subgenus of Leishmania parasites containing human pathogens.


Assuntos
Leishmania enriettii/classificação , Leishmania enriettii/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Feminino , Gana , Humanos , Leishmania enriettii/genética , Leishmaniose Cutânea/diagnóstico , Masculino , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase , RNA Polimerase II/genética , Proteínas Ribossômicas/genética , Análise de Sequência de DNA , Adulto Jovem
7.
PLoS Negl Trop Dis ; 8(2): e2630, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24516676

RESUMO

BACKGROUND: Leishmania major and an uncharacterized species have been reported from human patients in a cutaneous leishmaniasis (CL) outbreak area in Ghana. Reports from the area indicate the presence of anthropophilic Sergentomyia species that were found with Leishmania DNA. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we analyzed the Leishmania DNA positive sand fly pools by PCR-RFLP and ITS1 gene sequencing. The trypanosome was determined using the SSU rRNA gene sequence. We observed DNA of L. major, L. tropica and Trypanosoma species to be associated with the sand fly infections. This study provides the first detection of L. tropica DNA and Trypanosoma species as well as the confirmation of L. major DNA within Sergentomyia sand flies in Ghana and suggests that S. ingrami and S. hamoni are possible vectors of CL in the study area. CONCLUSIONS/SIGNIFICANCE: The detection of L. tropica DNA in this CL focus is a novel finding in Ghana as well as West Africa. In addition, the unexpected infection of Trypanosoma DNA within S. africana africana indicates that more attention is necessary when identifying parasitic organisms by PCR within sand fly vectors in Ghana and other areas where leishmaniasis is endemic.


Assuntos
DNA de Protozoário/análise , Leishmania tropica/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Psychodidae/parasitologia , Trypanosoma/isolamento & purificação , Animais , DNA de Protozoário/genética , Feminino , Gana , Humanos , Leishmania tropica/genética , Trypanosoma/genética
8.
Mil Med ; 178(3): 306-14, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23707118

RESUMO

Militaries are especially susceptible to operationally important outbreaks of acute respiratory infections such as pandemic and seasonal influenza. In addition, militaries play important roles for State Parties working to meet International Health Regulations 2005, particularly in developing countries. In 2009, the U.S. Naval Medical Research Unit No. 3 joined with the Noguchi Memorial Institute for Medical Research and the armed forces of Ghana, Burkina Faso, and Côte d'Ivoire to create or improve influenza surveillance capacities within the militaries. This article describes the process undertaken to achieve this goal. In the Ghana Armed Forces, influenza surveillance for outpatients was instituted at seven medical stations throughout the country and for inpatients at the tertiary referral hospital in Accra. As a result, military sites now contribute around half of the influenza cases detected in Ghana and reported weekly to the World Health Organization. Samples were also collected by the militaries of Côte d'Ivoire and Burkina Faso, although political instability slowed progress. This effort is part of an ongoing strategy to build influenza surveillance capacity within West African militaries in support of military services, global outbreak investigations, International Health Regulations-2005, and the development of country-specific pandemic preparedness plans.


Assuntos
Países em Desenvolvimento , Surtos de Doenças/estatística & dados numéricos , Influenza Humana/epidemiologia , Militares , Vigilância da População/métodos , África Ocidental/epidemiologia , Humanos , Estudos Retrospectivos
9.
MSMR ; 20(2): 25-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23461308

RESUMO

Multi-drug resistant Neisseria gonorrhoeae (GC) threatens the successful treatment of gonorrhea. This report presents preliminary findings with regard to the prevalence of laboratory-confirmed GC and the extent of drug-resistance among sample populations in five countries. Between October 2010 and January 2013, 1,694 subjects (54% male; 45% female; 1% unknown) were enrolled and screened for the presence of laboratory-confirmed GC in the United States, Djibouti, Ghana, Kenya, and Peru. Overall, 108 (6%) of enrolled subjects tested positive for GC. Antimicrobial susceptibility testing results were available for 66 GC isolates. Resistance to at least three antibiotics was observed at each overseas site. All isolates tested in Ghana (n=6) were resistant to ciprofloxacin, penicillin, and tetracycline. In Djibouti, preliminary results suggested resistance to penicillin, tetracycline, ciprofloxacin, cefepime, and ceftriaxone. The small sample size and missing data prevent comparative analysis and limit the generalizability of these preliminary findings.


Assuntos
Farmacorresistência Bacteriana Múltipla , Gonorreia/epidemiologia , Gonorreia/microbiologia , Medicina Militar , Neisseria gonorrhoeae , Vigilância da População , Antibacterianos , Djibuti/epidemiologia , Feminino , Gana/epidemiologia , Humanos , Quênia/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Peru/epidemiologia , Estados Unidos/epidemiologia , Uretra/microbiologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-21765823

RESUMO

Human cutaneous leishmaniasis (CL) has previously been reported in West Africa, but more recently, sporadic reports of CL have increased. Leishmania major has been identified from Mauritania, Senegal, Mali, and Burkina Faso. Three zymodemes (MON-26, MON-117, and MON-74, the most frequent) have been found. The geographic range of leishmaniasis is limited by the sand fly vector, its feeding preferences, and its capacity to support internal development of specific species of Leishmania. The risk of acquiring CL has been reported to increase considerably with human activity and epidemics of CL have been associated with deforestation, road construction, wars, or other activities where humans intrude the habitat of the vector. In the Ho Municipality in the Volta Region of Ghana, a localised outbreak of skin ulcers, possibly CL, was noted in 2003 without any such documented activity. This outbreak was consistent with CL as evidenced using various methods including parasite identification, albeit, in a small number of patients with ulcers. This paper reports the outbreak in Ghana. The report does not address a single planned study but rather a compilation of data from a number of ad-hoc investigations in response to the outbreak plus observations and findings made by the authors. It acknowledges that a number of the observations need to be further clarified. What is the detailed epidemiology of the disease? What sparked the epidemic? Can it happen again? What was the causative agent of the disease, L. major or some other Leishmania spp.? What were the main vectors and animal reservoirs? What are the consequences for surveillance of the disease and the prevention of its reoccurrence when the communities see a self-healing disease and may not think it is important?


Assuntos
Surtos de Doenças , Insetos Vetores/parasitologia , Leishmania major/patogenicidade , Leishmaniose Cutânea/epidemiologia , Psychodidae/parasitologia , Animais , Análise por Conglomerados , Doenças Endêmicas , Gana/epidemiologia , Humanos , Leishmania major/parasitologia , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/transmissão
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