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1.
Malar J ; 22(1): 57, 2023 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36805673

RESUMO

BACKGROUND: Vector populations are a key target for malaria control and elimination. In Honduras, there are at least 12 reported anopheline species, however, the definitive number of species remains uncertain. Due to the inherent limitations of morphological identification of Anopheles species, molecular approaches have been developed to provide accurate identification and robust surveillance of local malaria vectors. The aim of this study was to design and assess three PCR-RFLP assays to identify anopheline species known to presently occur in Honduras. METHODS: Mosquitoes captured between 2018 and 2022 in seven malaria-endemic and non-endemic departments in Honduras were analysed. The ITS2 ribosomal region and three restriction enzyme-based assays were evaluated in silico and experimentally. RESULTS: A total of 132 sequences from 12 anopheline species were analysed. The ITS2 marker showed length polymorphisms that generated products between 388 and 592 bp and no relevant intraspecies polymorphisms were found. Furthermore, the three PCR-RFLP assays were able to differentiate 11 species with sufficient precision and resolution. CONCLUSION: The ITS2 region was shown to be a useful molecular marker for identifying local Anopheles species. In addition, the PCR-RFLP assays evaluated here proved to be capable of discriminating most of the anopheline species present in Honduras. These methods provide alternatives to improve entomological surveillance of Anopheles in Honduras and other Mesoamerican countries.


Assuntos
Anopheles , Animais , Anopheles/genética , Polimorfismo de Fragmento de Restrição , Honduras , Mosquitos Vetores/genética , Reação em Cadeia da Polimerase
2.
Malar J ; 22(1): 110, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36978056

RESUMO

BACKGROUND: Malaria remains a main parasitic disease of humans. Although the largest number of cases is reported in the African region, there are still endemic foci in the Americas. Central America reported 36,000 malaria cases in 2020, which represents 5.5% of cases in the Americas and 0.015% of cases globally. Most malaria infections in Central America are reported in La Moskitia, shared by Honduras and Nicaragua. In the Honduran Moskitia, less than 800 cases were registered in 2020, considering it an area of low endemicity. In low endemicity settings, the number of submicroscopic and asymptomatic infections tends to increase, leaving many cases undetected and untreated. These reservoirs challenge national malaria elimination programmes. This study aimed to assess the diagnostic performance of Light Microscopy (LM), a nested PCR test and a photoinduced electron transfer polymerase chain reaction (PET-PCR) in a population of febrile patients from La Moskitia. METHODS: A total of 309 febrile participants were recruited using a passive surveillance approach at the Puerto Lempira hospital. Blood samples were analysed by LM, nested PCR, and PET-PCR. Diagnostic performance including sensitivity, specificity, negative and positive predictive values, kappa index, accuracy, and ROC analysis was evaluated. The parasitaemia of the positive samples was quantified by both LM and PET-PCR. RESULTS: The overall prevalence of malaria was 19.1% by LM, 27.8% by nPCR, and 31.1% by PET-PCR. The sensitivity of LM was 67.4% compared to nPCR, and the sensitivity of LM and nPCR was 59.6% and 80.8%, respectively, compared to PET-PCR. LM showed a kappa index of 0.67, with a moderate level of agreement. Forty positive cases by PET-PCR were not detected by LM. CONCLUSIONS: This study demonstrated that LM is unable to detect parasitaemia at low levels and that there is a high degree of submicroscopic infections in the Honduran Moskitia.


Assuntos
Malária Falciparum , Malária , Humanos , Malária/epidemiologia , Malária/diagnóstico , Reação em Cadeia da Polimerase , Técnicas de Amplificação de Ácido Nucleico , Parasitemia/epidemiologia , Tomografia por Emissão de Pósitrons , Malária Falciparum/parasitologia , Sensibilidade e Especificidade , Plasmodium falciparum/genética
3.
Malar J ; 20(1): 465, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34906144

RESUMO

BACKGROUND: Central America and the island of Hispaniola have set out to eliminate malaria by 2030. However, since 2014 a notable upturn in the number of cases has been reported in the Mosquitia region shared by Nicaragua and Honduras. In addition, the proportion of Plasmodium falciparum malaria cases has increased significantly relative to vivax malaria. Chloroquine continues to be the first-line drug to treat uncomplicated malaria in the region. The objective of this study was to evaluate the emergence of chloroquine resistant strains of P. falciparum using a genetic approach. Plasmodium vivax populations are not analysed in this study. METHODS: 205 blood samples from patients infected with P. falciparum between 2018 and 2021 were analysed. The pfcrt gene fragment encompassing codons 72-76 was analysed. Likewise, three fragments of the pfmdr1 gene were analysed in 51 samples by nested PCR and sequencing. RESULTS: All samples revealed the CVMNK wild phenotype for the pfcrt gene and the N86, Y184F, S1034C, N1042D, D1246 phenotype for the pfmdr1 gene. CONCLUSIONS: The increase in falciparum malaria cases in Nicaragua and Honduras cannot be attributed to the emergence of chloroquine-resistant mutants. Other possibilities should be investigated further. This is the first study to report the genotype of pfmdr1 for five loci of interest in Central America.


Assuntos
Antimaláricos/farmacologia , Resistência a Medicamentos/genética , Proteínas de Membrana Transportadoras/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Marcadores Genéticos , Honduras , Malária Falciparum/parasitologia , Proteínas de Membrana Transportadoras/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Nicarágua , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo
4.
Clin Infect Dis ; 69(8): 1440-1442, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-30753364

RESUMO

Despite glucose-6-phosphate dehydrogenase (G6PD) deficiency prevalence of 5% in the Amazon, primaquine is administered without G6PD screening. This is an important cause of hospitalization among Plasmodium vivax-infected individuals, leading to life-threatening anemia and acute renal failure across endemic areas. In Manaus, the frequency of primaquine-induced hemolysis was 85.2 cases per 100 000 primaquine users.


Assuntos
Antimaláricos/uso terapêutico , Deficiência de Glucosefosfato Desidrogenase/complicações , Malária Vivax/complicações , Plasmodium vivax/fisiologia , Primaquina/uso terapêutico , Insuficiência Renal/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia/etiologia , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Hemólise/efeitos dos fármacos , Humanos , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
5.
Malar J ; 18(1): 31, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30704496

RESUMO

BACKGROUND: Malaria is an important disease in many tropical countries. Rapid diagnostic tests (RDTs) are valuable tools for diagnosing malaria in remote areas. The majority of RDTs used for the diagnosis of Plasmodium falciparum are based on the detection of the specific histidine-rich proteins (PfHRP2 and PfHRP3). During the last decade, the threat posed by the lack of expression of these antigens and the variability of the proteins on the diagnosis of malaria has been widely discussed. The aim of this study was to evaluate the genetic diversity of pfhrp2 and pfhrp3 of P. falciparum isolates collected in three Central American countries. METHODS: DNA samples were amplified and sequenced to assess the diversity of nucleotides and amino acids. A search for known epitopes within the amino acid sequence was carried out, and the sensitivity of the sequences was evaluated according to a predictive model. A phylogenetic analysis was carried out including homologous sequences from different regions of the world. Protein structures were predicted in silico. RESULTS: Five different patterns for PfHRP2 and one pattern for PfHRP3 were identified. Isolates from Central America show a high level of genetic diversity in pfhrp2; however, the amino acid sequences seem to contain enough motifs to be detected by the RDTs currently available. CONCLUSION: It is unlikely that the variability of the pfhrp2 and pfhrp3 genes has a significant impact on the ability of the RDTs to detect the PfHRP antigens in Central America.


Assuntos
Antígenos de Protozoários/genética , Variação Genética , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Antígenos de Protozoários/química , Testes Diagnósticos de Rotina , Guatemala , Honduras , Nicarágua , Filogenia , Estrutura Terciária de Proteína , Proteínas de Protozoários/química
6.
Malar J ; 17(1): 320, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30170596

RESUMO

BACKGROUND: Malaria remains a public health problem in some countries of Central America. Rapid diagnostic tests (RDTs) are one of the most useful tools to assist in the diagnosis of malaria in remote areas. Since its introduction, a wide variety of RDTs have been developed for the detection of different parasite antigens. PfHRP2 is the most targeted antigen for the detection of Plasmodium falciparum infections. Genetic mutations and gene deletions are important factors influencing or affecting the performance of rapid diagnostic tests. METHODS: In order to demonstrate the presence or absence of the pfhrp2 and pfhrp3 genes and their flanking regions, a total of 128 blood samples from patients with P. falciparum infection from three Central American countries were analysed through nested or semi-nested PCR approaches. RESULTS: In total, 25.8 and 91.4% of the isolates lacked the region located between exon 1 and exon 2 of pfhrp2 and pfhrp3 genes, respectively. Parasites from the three countries showed deletions of one or both genes. The highest proportion of pfhrp2 deletions was found in Nicaragua while the isolates from Guatemala revealed the lowest number of pfhrp2 deletions. Parasites collected from Honduras showed the highest proportion of phfrp3 absence (96.2%). Twenty-one percent of isolates were double negative mutants for the exon 1-2 segment of both genes, and 6.3% of isolates lacked the full-length coding region of both genes. CONCLUSIONS: This study provides molecular evidence of the existence of P. falciparum isolates lacking the pfhrp2 and pfhrp3 genes, and their flanking regions, in Honduras, Guatemala and Nicaragua. This finding could hinder progress in the control and elimination of malaria in Central America. Continuous evaluation of RDTs and molecular surveillance would be recommended.


Assuntos
Antígenos de Protozoários/genética , Sequência de Bases , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Deleção de Sequência , DNA Intergênico , Guatemala , Honduras , Humanos , Nicarágua
7.
Malar J ; 17(1): 415, 2018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30409136

RESUMO

BACKGROUND: The incidence of malaria in the Americas has decreased markedly in recent years. Honduras and the other countries of Mesoamerica and the island of Hispaniola have set the goal of eliminating native malaria by the year 2020. To achieve this goal, Honduras has recently approved national regulations to expand the possibilities of a shortened double dose primaquine (PQ) treatment for vivax malaria. Considering this new shortened anti-malarial treatment, the high frequency of G6PDd genotypes in Honduras, and the lack of routinely assessment of the G6PD deficiency status, this study aimed at investigating the potential association between the intake of PQ and haemolysis in malaria-infected G6PDd subjects. METHODS: This was a prospective cohort and open-label study. Participants with malaria were recruited. Plasmodium vivax infection was treated with 0.25 mg/kg of PQ daily for 14 days. Safety and signs of haemolysis were evaluated by clinical criteria and laboratory values before and during the 3rd and 7th day of PQ treatment. G6PD status was assessed by a rapid test (CareStart™) and two molecular approaches. RESULTS: Overall 55 participants were enrolled. The frequency of G6PD deficient genotypes was 7/55 (12.7%), where 5/7 (71.4%) were hemizygous A- males and 2/7 (28.6%) heterozygous A- females. Haemoglobin concentrations were compared between G6PD wild type (B) and G6PDd A- subjects, showing a significant difference between the means of both groups in the 3rd and 7th days. Furthermore, a statistically significant difference was evident in the change in haemoglobin concentration between the 3rd day and the 1st day for both genotypes, but there was no statistical difference for the change in haemoglobin concentration between the 7th day and the 1st day. Besides these changes in the haemoglobin concentrations, none of the patients showed signs or symptoms associated with severe haemolysis, and none needed to be admitted to a hospital for further medical attention. CONCLUSIONS: The findings support that the intake of PQ during 14 days of treatment against vivax malaria is safe in patients with a class III variant of G6PDd. In view of the new national regulations in the shortened treatment of vivax malaria for 7 days, it is advisable to be alert of potential cases of severe haemolysis that could occur among G6PD deficient hemizygous males with a class II mutation such as the Santamaria variant, previously reported in the country.


Assuntos
Antimaláricos/uso terapêutico , Deficiência de Glucosefosfato Desidrogenase/fisiopatologia , Hemólise , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Primaquina/uso terapêutico , Adolescente , Adulto , Idoso , Criança , Feminino , Honduras , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Risco , Adulto Jovem
8.
Malar J ; 16(1): 495, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29273053

RESUMO

BACKGROUND: Respiratory complications are uncommon, but often life-threatening features of Plasmodium vivax malaria. This study aimed to estimate the prevalence and lethality associated with such complications among P. vivax malaria patients in a tertiary hospital in the Western Brazilian Amazon, and to identify variables associated with severe respiratory complications, intensive care need and death. Medical records from 2009 to 2016 were reviewed aiming to identify all patients diagnosed with P. vivax malaria and respiratory complications. Prevalence, lethality and risk factors associated with WHO defined respiratory complications, intensive care need and death were assessed. RESULTS: A total of 587 vivax malaria patients were hospitalized during the study period. Thirty (5.1%) developed respiratory complications. Thirteen (43.3%) developed severe respiratory complications, intensive care was required for 12 (40%) patients and 5 (16.6%) died. On admission, anaemia and thrombocytopaenia were common findings, whereas fever was unusual. Patients presented different classes of parasitaemia and six were aparasitaemic on admission. Time to respiratory complications occurred after anti-malarials administration in 18 (60%) patients and progressed very rapidly. Seventeen patients (56.7%) had comorbidities and/or concomitant conditions, which were significantly associated to higher odds of developing severe respiratory complications, need for intensive care and death (p < 0.05). CONCLUSION: Respiratory complications were shown to be associated with significant mortality in this population. Patients with comorbidities and/or concomitant conditions require special attention to avoid this potential life-threatening complication.


Assuntos
Malária Vivax/complicações , Malária Vivax/parasitologia , Plasmodium vivax/isolamento & purificação , Síndrome do Desconforto Respiratório/parasitologia , Adulto , Anemia/epidemiologia , Anemia/etiologia , Anemia/parasitologia , Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Brasil/epidemiologia , Cuidados Críticos , Feminino , Hospitalização , Humanos , Pulmão/patologia , Malária Vivax/epidemiologia , Masculino , Pessoa de Meia-Idade , Parasitemia/parasitologia , Prevalência , Síndrome do Desconforto Respiratório/etiologia , Fatores de Risco , Índice de Gravidade de Doença , Centros de Atenção Terciária , Trombocitopenia/epidemiologia , Trombocitopenia/etiologia , Trombocitopenia/parasitologia , Adulto Jovem
9.
Malar J ; 14: 308, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26249834

RESUMO

BACKGROUND: The frequency of deficient variants of glucose-6-phosphate dehydrogenase (G6PDd) is particularly high in areas where malaria is endemic. The administration of antirelapse drugs, such as primaquine, has the potential to trigger an oxidative event in G6PD-deficient individuals. According to Honduras´ national scheme, malaria treatment requires the administration of chloroquine and primaquine for both Plasmodium vivax and Plasmodium falciparum infections. The present study aimed at investigating for the first time in Honduras the frequency of the two most common G6PDd variants. METHODS: This was a descriptive study utilizing 398 archival DNA samples of patients that had been diagnosed with malaria due to P. vivax, P. falciparum, or both. The most common allelic variants of G6PD: G6PD A+(376G) and G6PD A-(376G/202A) were assessed by two molecular methods (PCR-RFLP and a commercial kit). RESULTS: The overall frequency of G6PD deficient genotypes was 16.08%. The frequency of the "African" genotype A- (Class III) was 11.9% (4.1% A- hemizygous males; 1.5% homozygous A- females; and 6.3% heterozygous A- females). A high frequency of G6PDd alleles was observed in samples from malaria patients residing in endemic regions of Northern Honduras. One case of Santamaria mutation (376G/542T) was detected. CONCLUSIONS: Compared to other studies in the Americas, as well as to data from predictive models, the present study identified a higher-than expected frequency of genotype A- in Honduras. Considering that the national standard of malaria treatment in the country includes primaquine, further research is necessary to ascertain the risk of PQ-triggered haemolytic reactions in sectors of the population more likely to carry G6PD mutations. Additionally, consideration should be given to utilizing point of care technologies to detect this genetic disorder prior administration of 8-aminoquinoline drugs, either primaquine or any new drug available in the near future.


Assuntos
Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Feminino , Frequência do Gene , Deficiência de Glucosefosfato Desidrogenase/sangue , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Deficiência de Glucosefosfato Desidrogenase/genética , Honduras/epidemiologia , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência
10.
Malar J ; 14: 19, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25604310

RESUMO

BACKGROUND: Recent studies have demonstrated the deletion of the histidine-rich protein 2 (PfHRP2) gene (pfhrp2) in field isolates of Plasmodium falciparum, which could result in false negative test results when PfHRP2-based rapid diagnostic tests (RDTs) are used for malaria diagnosis. Although primary diagnosis of malaria in Honduras is determined based on microscopy, RDTs may be useful in remote areas. In this study, it was investigated whether there are deletions of the pfhrp2, pfhrp3 and their respective flanking genes in 68 P. falciparum parasite isolates collected from the city of Puerto Lempira, Honduras. In addition, further investigation considered the possible correlation between parasite population structure and the distribution of these gene deletions by genotyping seven neutral microsatellites. METHODS: Sixty-eight samples used in this study, which were obtained from a previous chloroquine efficacy study, were utilized in the analysis. All samples were genotyped for pfhrp2, pfhrp3 and flanking genes by PCR. The samples were then genotyped for seven neutral microsatellites in order to determine the parasite population structure in Puerto Lempira at the time of sample collection. RESULTS: It was found that all samples were positive for pfhrp2 and its flanking genes on chromosome 8. However, only 50% of the samples were positive for pfhrp3 and its neighboring genes while the rest were either pfhrp3-negative only or had deleted a combination of pfhrp3 and its neighbouring genes on chromosome 13. Population structure analysis predicted that there are at least two distinct parasite population clusters in this sample population. It was also determined that a greater proportion of parasites with pfhrp3-(and flanking gene) deletions belonged to one cluster compared to the other. CONCLUSION: The findings indicate that the P. falciparum parasite population in the municipality of Puerto Lempira maintains the pfhrp2 gene and that PfHRP2-based RDTs could be considered for use in this region; however continued monitoring of parasite population will be useful to detect any parasites with deletions of pfhrp2.


Assuntos
Antígenos de Protozoários/genética , Erros de Diagnóstico , Testes Diagnósticos de Rotina/métodos , Deleção de Genes , Malária Falciparum/diagnóstico , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Genótipo , Honduras , Humanos , Lactente , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Plasmodium falciparum/classificação , Plasmodium falciparum/isolamento & purificação , Reação em Cadeia da Polimerase , Prevalência , Estudos Retrospectivos , Adulto Jovem
11.
Exp Parasitol ; 151-152: 80-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25680279

RESUMO

Amoebiasis caused by Entamoeba histolytica continues to be one of the most common parasitic diseases in the developing world. Despite its relevance, due to the lack of accurate diagnostic methods, the true clinical and public health importance of this parasite remains uncertain. The aim of this study was to develop a new diagnostic tool to differentiate E.histolytica from the morphologically undistinguishable E.dispar and E.moshkovskii. We developed a specific, fast and simple PCR-RFLP method that was able to accurately differentiate experimentally-obtained restriction patterns from the three Entamoeba species. This new method could prove useful for clinical and epidemiological purposes.


Assuntos
Entamoeba/classificação , Entamebíase/diagnóstico , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Mapeamento por Restrição , Desoxirribonucleases de Sítio Específico do Tipo II , Diagnóstico Diferencial , Entamoeba/genética , Entamoeba/isolamento & purificação , Entamoeba histolytica/classificação , Entamoeba histolytica/genética , Entamoeba histolytica/isolamento & purificação , Entamebíase/parasitologia , Humanos , Reação em Cadeia da Polimerase/normas
12.
Hemoglobin ; 39(2): 134-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25707678

RESUMO

Sickle cell disease is the most common hemoglobinopathy worldwide, particularly in Africa and among people of African descent. Serious clinical consequences characterize the homozygous condition. To determine the prevalence of Hb S (HBB: c.20A > T) and anemia in a community of people of African descent from Honduras, 202 individuals were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The high prevalence found indicates that it is necessary to implement a program to prevent the consequences of this disease in vulnerable populations of Honduras.


Assuntos
Anemia Falciforme/epidemiologia , Anemia Falciforme/genética , População Negra/genética , Hemoglobina Falciforme/genética , Mutação , Globinas beta/genética , Adolescente , Anemia Falciforme/diagnóstico , Criança , Pré-Escolar , Feminino , Frequência do Gene , Geografia , Homozigoto , Honduras/epidemiologia , Humanos , Lactente , Masculino , Polimorfismo de Fragmento de Restrição , Gravidez , Prevalência , Adulto Jovem
13.
Mem Inst Oswaldo Cruz ; 109(4): 492-3, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25075788

RESUMO

Countries could use the monitoring of drug resistance in malaria parasites as an effective early warning system to develop the timely response mechanisms that are required to avert the further spread of malaria. Drug resistance surveillance is essential in areas where no drug resistance has been reported, especially if neighbouring countries have previously reported resistance. Here, we present the results of a four-year surveillance program based on the sequencing of the pfcrt gene of Plasmodium falciparum populations from endemic areas of Honduras. All isolates were susceptible to chloroquine, as revealed by the pfcrt "CVMNK" genotype in codons 72-76.


Assuntos
Antimaláricos/farmacologia , Cloroquina/farmacologia , Resistência a Medicamentos/genética , Plasmodium falciparum/efeitos dos fármacos , DNA de Protozoário/genética , Genótipo , Honduras , Humanos , Plasmodium falciparum/genética , Plasmodium falciparum/isolamento & purificação , Vigilância da População , Proteínas de Protozoários/genética
14.
J Fungi (Basel) ; 10(3)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38535195

RESUMO

Kodamaea ohmeri is an environmental yeast considered a rare emerging pathogen. In clinical settings, the correct identification of this yeast is relevant because some isolates are associated with resistance to antifungals. There is a lack of available data regarding the geographical distribution, virulence, and drug resistance profile of K. ohmeri. To contribute to the knowledge of this yeast, this study aimed to describe in depth three isolates of K. ohmeri associated with fungemia in Honduras. The identification of the isolates was carried out by sequencing the ribosomal ITS region. In addition, the susceptibility profile to antifungals was determined, and some properties associated with virulence were evaluated (exoenzyme production, biofilm formation, cell adhesion, and invasion). The isolates showed strong protease, phospholipase, and hemolysin activity, in addition to being biofilm producers. Adherence and invasion capacity were evident in the HeLa and Raw 264.7 cell lines, respectively. This study expands the understanding of the underlying biological traits associated with virulence in K. ohmeri, and it is the first report of the detection and identification of K. ohmeri in Honduras as a cause of human infection.

15.
Malar J ; 12: 354, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24093629

RESUMO

BACKGROUND: The Caribbean coast of Central America remains an area of malaria transmission caused by Plasmodium falciparum despite the fact that morbidity has been reduced in recent years. Parasite populations in that region show interesting characteristics such as chloroquine susceptibility and low mortality rates. Genetic structure and diversity of P. falciparum populations in the Honduras-Nicaragua border were analysed in this study. METHODS: Seven neutral microsatellite loci were analysed in 110 P. falciparum isolates from endemic areas of Honduras (n = 77) and Nicaragua (n = 33), mostly from the border region called the Moskitia. Several analyses concerning the genetic diversity, linkage disequilibrium, population structure, molecular variance, and haplotype clustering were conducted. RESULTS: There was a low level of genetic diversity in P. falciparum populations from Honduras and Nicaragua. Expected heterozigosity (H(e)) results were similarly low for both populations. A moderate differentiation was revealed by the F(ST) index between both populations, and two putative clusters were defined through a structure analysis. The main cluster grouped most of samples from Honduras and Nicaragua, while the second cluster was smaller and included all the samples from the Siuna community in Nicaragua. This result could partially explain the stronger linkage disequilibrium (LD) in the parasite population from that country. These findings are congruent with the decreasing rates of malaria endemicity in Central America.


Assuntos
Variação Genética , Malária Falciparum/parasitologia , Plasmodium falciparum/classificação , Plasmodium falciparum/genética , Análise por Conglomerados , DNA de Protozoário/genética , Doenças Endêmicas , Honduras , Humanos , Malária Falciparum/epidemiologia , Repetições de Microssatélites , Epidemiologia Molecular , Nicarágua/epidemiologia , Filogenia , Plasmodium falciparum/isolamento & purificação
16.
Travel Med Infect Dis ; 53: 102567, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36958705

RESUMO

Recently, there has been a significant increase in irregular migration from Central America's northern triangle (Honduras, Guatemala and El Salvador). Hondurans who migrate to North America face numerous risks to their lives and health. Infectious diseases are one of the most serious threats to migrants both during the migration process and once they arrive in the host country. The major infectious diseases affecting both migrants and the health services in non-endemic countries that care for these migrants are discussed.


Assuntos
Doenças Transmissíveis , Migração Humana , Humanos , América do Norte , Honduras/epidemiologia , El Salvador/epidemiologia , Guatemala/epidemiologia , Doenças Transmissíveis/epidemiologia
17.
Trop Med Infect Dis ; 8(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37505641

RESUMO

Several studies have documented the presence of Acinetobacter baumannii, a known multi-drug-resistant pathogen, in the human head louse, Pediculus humanus capitis. Since no reports from countries in Latin America have been published, the aim of the present study was to determine whether A. baumannii was present in head lice specimens collected in this geographic region. Head lice specimens from Argentina, Colombia, and Honduras were analyzed. PCR assays were performed to confirm the specimens' species and to investigate whether the DNA of A. baumannii was present. The products of the latter were sequenced to confirm bacterial identity. Altogether, 122 pools of head lice were analyzed, of which two (1.64%) were positive for A. baumannii's DNA. The positive head lice had been collected at the poorest study site in Honduras. The remaining specimens were negative. This study is the first to report the presence of A. baumannii in human head lice from Latin America. Further investigations are required to elucidate whether these ectoparasites can serve as natural reservoirs or even effectively transmit A. baumannii to humans.

18.
Malar J ; 11: 391, 2012 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-23181845

RESUMO

BACKGROUND: Understanding the population structure of Plasmodium species through genetic diversity studies can assist in the design of more effective malaria control strategies, particularly in vaccine development. Central America is an area where malaria is a public health problem, but little is known about the genetic diversity of the parasite's circulating species. This study aimed to investigate the allelic frequency and molecular diversity of five surface antigens in field isolates from Honduras. METHODS: Five molecular markers were analysed to determine the genotypes of Plasmodium vivax and Plasmodium falciparum from endemic areas in Honduras. Genetic diversity of ama-1, msp-1 and csp was investigated for P. vivax, and msp-1 and msp-2 for P. falciparum. Allelic frequencies were calculated and sequence analysis performed. RESULTS AND CONCLUSION: A high genetic diversity was observed within Plasmodium isolates from Honduras. A different number of genotypes were elucidated: 41 (n = 77) for pvama-1; 23 (n = 84) for pvcsp; and 23 (n = 35) for pfmsp-1. Pvcsp sequences showed VK210 as the only subtype present in Honduran isolates. Pvmsp-1 (F2) was the most polymorphic marker for P. vivax isolates while pvama-1 was least variable. All three allelic families described for pfmsp-1 (n = 30) block 2 (K1, MAD20, and RO33), and both allelic families described for the central domain of pfmsp-2 (n = 11) (3D7 and FC27) were detected. However, K1 and 3D7 allelic families were predominant. All markers were randomly distributed across the country and no geographic correlation was found. To date, this is the most complete report on molecular characterization of P. vivax and P. falciparum field isolates in Honduras with regards to genetic diversity. These results indicate that P. vivax and P. falciparum parasite populations are highly diverse in Honduras despite the low level of transmission.


Assuntos
Antígenos de Protozoários/genética , Variação Genética , Plasmodium falciparum/classificação , Plasmodium falciparum/genética , Plasmodium vivax/classificação , Plasmodium vivax/genética , DNA de Protozoário/química , DNA de Protozoário/genética , Frequência do Gene , Genótipo , Honduras , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Dados de Sequência Molecular , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Análise de Sequência de DNA
19.
Malar J ; 11: 119, 2012 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-22513192

RESUMO

BACKGROUND: Honduras is a tropical country with more than 70% of its population living at risk of being infected with either Plasmodium vivax or Plasmodium falciparum. Laboratory diagnosis is a very important factor for adequate treatment and management of malaria. In Honduras, malaria is diagnosed by both, microscopy and rapid diagnostic tests and to date, no molecular methods have been implemented for routine diagnosis. However, since mixed infections, and asymptomatic and low-parasitaemic cases are difficult to detect by light microscopy alone, identifying appropriate molecular tools for diagnostic applications in Honduras deserves further study. The present study investigated the utility of different molecular tests for the diagnosis of malaria in Honduras. METHODS: A total of 138 blood samples collected as part of a clinical trial to assess the efficacy of chloroquine were used: 69 microscopically confirmed P. falciparum positive samples obtained on the day of enrollment and 69 follow-up samples obtained 28 days after chloroquine treatment and shown to be malaria negative by microscopy. Sensitivity and specificity of microscopy was compared to an 18 s ribosomal RNA gene-based nested PCR, two single-PCR reactions designed to detect Plasmodium falciparum infections, one single-PCR to detect Plasmodium vivax infections, and one multiplex one-step PCR reaction to detect both parasite species. RESULTS: Of the 69 microscopically positive P. falciparum samples, 68 were confirmed to be P. falciparum-positive by two of the molecular tests used. The one sample not detected as P. falciparum by any of the molecular tests was shown to be P. vivax-positive by a reference molecular test indicating a misdiagnosis by microscopy. The reference molecular test detected five cases of P. vivax/P. falciparum mixed infections, which were not recognized by microscopy as mixed infections. Only two of these mixed infections were recognized by a multiplex test while a P. vivax-specific polymerase chain reaction (PCR) detected three of them. In addition, one of the day 28 samples, previously determined to be malaria negative by microscopy, was shown to be P. vivax-positive by three of the molecular tests specific for this parasite. CONCLUSIONS: Molecular tests are valuable tools for the confirmation of Plasmodium species and in detecting mixed infections in malaria endemic regions.


Assuntos
Malária Falciparum/diagnóstico , Malária Vivax/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Parasitologia/métodos , Plasmodium falciparum/isolamento & purificação , Plasmodium vivax/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Primers do DNA/genética , Honduras , Humanos , Plasmodium falciparum/genética , Plasmodium vivax/genética , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Sensibilidade e Especificidade
20.
Trop Med Infect Dis ; 7(8)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35893657

RESUMO

The elimination of malaria requires strengthening diagnosis and offering adequate and timely treatment. Imported cases of falciparum malaria represent a major challenge for pre-elimination areas, such as Central America, where chloroquine and primaquine continue to be used as first-line treatment. The pfs47 gene has been previously described as a precise molecular marker to track the geographic origin of the parasite. The aim of this study was to design a simple and low-cost technique using the polymorphic region of pfs47 to assess the geographic origin of P. falciparum strains. A PCR-RFLP technique was developed and evaluated using the MseI enzyme that proved capable of discriminating, with reasonable precision, the geographical origin of the parasites. This method could be used by national surveillance laboratories and malaria elimination programs in countries such as Honduras and Nicaragua in cases of malaria where an origin outside the Central American isthmus is suspected.

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