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1.
J Med Virol ; 94(1): 366-371, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34546584

RESUMO

Co-epidemics happening simultaneously can generate a burden on healthcare systems. The co-occurrence of SARS-CoV-2 with vector-borne diseases (VBD), such as malaria and dengue in resource-limited settings represents an additional challenge to the healthcare systems. Herein, we assessed the coinfection rate between SARS-CoV-2 and VBD to highlight the need to carry out an accurate diagnosis and promote timely measures for these infections in Luanda, the capital city of Angola. This was a cross-sectional study conducted with 105 subjects tested for the SARS-CoV-2 and VBD with a rapid detection test in April 2021. The participants tested positive for SARS-CoV-2 (3.80%), malaria (13.3%), and dengue (27.6%). Low odds related to testing positivity to SARS-CoV-2 or VBD were observed in participants above or equal to 40 years (odds ratio [OR]: 0.60, p = 0.536), while higher odds were observed in male (OR: 1.44, p = 0.392) and urbanized areas (OR: 3.78, p = 0.223). The overall co-infection rate between SARS-CoV-2 and VBD was 11.4%. Our findings showed a coinfection between SARS-CoV-2 with malaria and dengue, which could indicate the need to integrate the screening for VBD in the SARS-CoV-2 testing algorithm and the adjustment of treatment protocols. Further studies are warranted to better elucidate the relationship between COVID-19 and VBD in Angola.


Assuntos
COVID-19/epidemiologia , Coinfecção/epidemiologia , Dengue/epidemiologia , Malária/epidemiologia , Doenças Transmitidas por Vetores/epidemiologia , Adolescente , Adulto , Fatores Etários , Angola/epidemiologia , Anticorpos Antiprotozoários/sangue , Anticorpos Antivirais/sangue , Teste para COVID-19 , Febre de Chikungunya/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , RNA Viral/sangue , SARS-CoV-2/isolamento & purificação , Fatores Sexuais , Adulto Jovem , Infecção por Zika virus/epidemiologia
2.
BMC Infect Dis ; 21(1): 1131, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34727874

RESUMO

BACKGROUND: SARS-CoV-2 emerged in China and spread throughout the world due to its rapid transmission. The exposure rate in the healthy population is unknown, mainly in resource-limited countries. Herein, we estimated the seroprevalence of anti-SARS-CoV-2 antibodies and risk factors among blood donors in Luanda, the capital city of Angola. METHODS: This was a retrospective study conducted with 343 blood donors. Chi-square and logistic regression were calculated to predict the independent variable for SARS-CoV-2 infection and deemed significant when p < 0.05. RESULTS: Seroprevalence of anti-SARS-CoV-2 was 4.7%. Positivity rates varied to age groups (3.5-14.3%), gender (0-5%), area of residence (3.1-.6%), educational level (5.1-10.2%), occupation (4.4-7.7%), and the blood donor category (2.0-5.1%). Past and recent infections were detected in 3.2% and 1.5%, respectively. Blood donors under the age of 20 years (OR: 4.58, p = 0.241) and from non-urbanized areas (OR: 1.86, p = 0.293) presented a high risk related to infection. The infection was higher in blood group A and lower in blood group O. The risk of SARS-CoV-2 infection has increased from January 2020 (OR: 0.03, p = 0.001) to August 2020 (OR: 0.57, p = 0.426). CONCLUSIONS: We provide an estimate of the exposure of healthy blood donors in Luanda. Also, we detected anti-SARS-CoV-2 in January 2020, indicating that the SARS-CoV-2 could have been imported during the first month of 2020. Further studies should be performed to assess the exposure rate in different groups from Angola.


Assuntos
Doadores de Sangue , COVID-19 , Adulto , Angola/epidemiologia , Anticorpos Antivirais , Estudos Transversais , Humanos , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Estudos Soroepidemiológicos , Adulto Jovem
3.
J Med Virol ; 92(12): 3265-3270, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32515502

RESUMO

Infectious diseases during pregnancy remain a public health concern, especially in a resource-limited setting. The study aimed to determine the seroprevalence and determinants of HIV and co-infection with hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis among pregnant women attending antenatal care in Luanda, the capital city of Angola. A cross-sectional study was conducted with 1612 pregnant women screened for HIV during antenatal care. HIV-reactive were also screened for the HBV, HCV, and syphilis using immunoassay kits. A logistic regression model, adjusted odds ratios (AOR) and their 95% confidence interval (CI) were calculated with a level of significance set at 5%. The overall seroprevalence of HIV was 2.6%. About 13% of HIV-positive pregnant women were coinfected. From which, 7.5% were reactive to HBV and 5% to syphilis. There was no reactivity to HCV. Pregnant women younger aged than 25 years were significantly protected from HIV-infection (AOR, 0.43 [95% CI, 0.20-0.91], P = .026). The co-infection was 1.3 times (AOR, 0.04-41.0) in younger aged than 25 years, 7.0 times (AOR, 0.50-99.2) to residents in urbanized areas, and 1.4 times (AOR, 0.10-20.9) in pregnant women with a high educational level. In conclusion, infectious diseases are a public health burden among pregnant women in Luanda. However, include an integrated antenatal screening mainly in urbanized areas is crucial to reduce the spread of infectious diseases in different communities of Angola.

5.
Vaccine ; 41 Suppl 1: A48-A57, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36803869

RESUMO

After six years without any detection of poliomyelitis cases, Angola reported a case of circulating vaccine-derived poliovirus type 2 (cVDPV2) with paralysis onset date of 27 March 2019. Ultimately, 141 cVDPV2 polio cases were reported in all 18 provinces in 2019-2020, with particularly large hotspots in the south-central provinces of Luanda, Cuanza Sul, and Huambo. Most cases were reported from August to December 2019, with a peak of 15 cases in October 2019. These cases were classified into five distinct genetic emergences (emergence groups) and have ties with cases identified in 2017-2018 in the Democratic Republic of Congo. From June 2019 to July 2020, the Angola Ministry of Health and partners conducted 30 supplementary immunization activity (SIA) rounds as part of 10 campaign groups, using monovalent OPV type 2 (mOPV2). There were Sabin 2 vaccine strain detections in the environmental (sewage) samples taken after mOPV2 SIAs in each province. Following the initial response, additional cVDPV2 polio cases occurred in other provinces. However, the national surveillance system did not detect any new cVDPV2 polio cases after 9 February 2020. While reporting subpar indicator performance in epidemiological surveillance, the laboratory and environmental data as of May 2021 strongly suggest that Angola successfully interrupted transmission of cVDPV2 early in 2020. Additionally, the COVID-19 pandemic did not allow a formal Outbreak Response Assessment (OBRA). Improving the sensitivity of the surveillance system and the completeness of AFP case investigations will be vital to promptly detect and interrupt viral transmission if a new case or sewage isolate are identified in Angola or central Africa.


Assuntos
COVID-19 , Poliomielite , Poliovirus , Humanos , Esgotos , Angola/epidemiologia , Pandemias , COVID-19/epidemiologia , Poliomielite/prevenção & controle , Vacina Antipólio Oral/efeitos adversos , Surtos de Doenças/prevenção & controle
6.
Influenza Other Respir Viruses ; 17(9): e13198, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37744993

RESUMO

Background: In Angola, COVID-19 cases have been reported in all provinces, resulting in >105,000 cases and >1900 deaths. However, no detailed genomic surveillance into the introduction and spread of the SARS-CoV-2 virus has been conducted in Angola. We aimed to investigate the emergence and epidemic progression during the peak of the COVID-19 pandemic in Angola. Methods: We generated 1210 whole-genome SARS-CoV-2 sequences, contributing West African data to the global context, that were phylogenetically compared against global strains. Virus movement events were inferred using ancestral state reconstruction. Results: The epidemic in Angola was marked by four distinct waves of infection, dominated by 12 virus lineages, including VOCs, VOIs, and the VUM C.16, which was unique to South-Western Africa and circulated for an extended period within the region. Virus exchanges occurred between Angola and its neighboring countries, and strong links with Brazil and Portugal reflected the historical and cultural ties shared between these countries. The first case likely originated from southern Africa. Conclusion: A lack of a robust genome surveillance network and strong dependence on out-of-country sequencing limit real-time data generation to achieve timely disease outbreak responses, which remains of the utmost importance to mitigate future disease outbreaks in Angola.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Angola/epidemiologia , Epidemiologia Molecular , Pandemias
7.
Am J Trop Med Hyg ; 106(3): 779-784, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35008058

RESUMO

Tuberculosis (TB) is a major cause of illness and public health concern, especially in resource-limited countries. This study analyzed the characteristics related to anti-TB drug resistance. Moreover, we examined the evidence-based indications for the treatment of active TB in Angola. This study evaluated the medical records of 176 patients screened for TB from January to September 2016 in Luanda, the capital city of Angola. Approximately 66.5% of the patients were newly diagnosed with active TB. The residence area showed a significant relationship with TB (P = 0.025), whereas age group (P = 0.272), gender (P = 0.853), and HIV status (P = 0.284) did not showed any relationship with TB. Overall, 72.4% of TB patients had resistance to at least one of the anti-TB drugs. The risk of anti-TB drug resistance was higher in males (odds ratio [OR]: 1.22; 95% confidence interval [CI]: 0.42-3.58, P = 0.685] and in TB-HIV coinfected patients [OR: 1.39; (95% CI: 0.26-7.28), P = 0.700], whereas it was lower in patients aged 30 years or older (OR: 0.56; 95% CI: 0.18-1.69) P = 0.303) and in patients living in urbanized areas (OR: 0.74; 95% CI: 0.17-3.25; P = 0.685). Our findings showed that drug-resistant TB is emerging in Angola. Further studies on factors related to anti-TB drug resistance are urgently needed to ascertain the magnitude of the problem and to proffer strategies toward TB control in Angola.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Angola/epidemiologia , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Masculino , Fatores de Risco , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
8.
Pathogens ; 11(5)2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35631076

RESUMO

Artemisinin (ART) is recommended as the first-line drug for P. falciparum infections combined with a long-acting partner drug. The emergence of P. falciparum resistance to ART (ARTR) is a concern for malaria. The most feared threat remains the spread of ARTR from Southeast Asia to Africa or the independent emergence of ARTR in Africa, where malaria accounts for 93% of all malaria cases and 94% of deaths. To avoid this worst-case scenario, surveillance of Pfkelch13 mutations is essential. We investigated mutations of Pfkelch13 in 78 P. falciparum samples from Huambo, Angola. Most of the parasites had a wild-type Pfkelch13 allele. We identified one synonymous mutation (R471R) in 10 isolates and one non-synonymous mutation (A578S) in two samples. No Pfkelch13 validated or candidate ARTR mutants were identified. The finding suggests that there is little polymorphism in Pfkelch13 in Huambo. Since cases of late response to ART in Africa and the emergence of ARTR mutations in Rwanda and Uganda have been reported, efforts should be made toward continuous molecular surveillance of ARTR. Our study has some limitations. Since we analyzed P. falciparum parasites from a single health facility, the study may not be representative of all Angolan endemic areas.

9.
PLoS Negl Trop Dis ; 16(5): e0010255, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35584153

RESUMO

BACKGROUND: The transmission patterns and genetic diversity of dengue virus (DENV) circulating in Africa remain poorly understood. Circulation of the DENV serotype 1 (DENV1) in Angola was detected in 2013, while DENV serotype 2 (DENV2) was detected in 2018. Here, we report results from molecular and genomic investigations conducted at the Ministry of Health national reference laboratory (INIS) in Angola on suspected dengue cases detected between January 2017 and February 2019. METHODS: A total of 401 serum samples from dengue suspected cases were collected in 13 of the 18 provinces in Angola. Of those, 351 samples had complete data for demographic and epidemiological analysis, including age, gender, province, type of residence, clinical symptoms, as well as dates of onset of symptoms and sample collection. RNA was extracted from residual samples and tested for DENV-RNA using two distinct real time RT-PCR protocols. On-site whole genome nanopore sequencing was performed on RT-PCR+ samples. Bayesian coalescent models were used to estimate date and origin of outbreak emergence, as well as population growth rates. RESULTS: Molecular screening showed that 66 out of 351 (19%) suspected cases were DENV-RNA positive across 5 provinces in Angola. DENV RT-PCR+ cases were detected more frequently in urban sites compared to rural sites. Of the DENV RT-PCR+ cases most were collected within 6 days of symptom onset. 93% of infections were confirmed by serotype-specific RT-PCR as DENV2 and 1 case (1.4%) was confirmed as DENV1. Six CHIKV RT-PCR+ cases were also detected during the study period, including 1 co-infection of CHIKV with DENV1. Most cases (87%) were detected in Luanda during the rainy season between April and October. Symptoms associated with severe dengue were observed in 11 patients, including 2 with a fatal outcome. On-site nanopore genome sequencing followed by genetic analysis revealed an introduction of DENV2 Cosmopolitan genotype (also known as DENV2-II genotype) possibly from India in or around October 2015, at least 1 year before its detection in the country. Coalescent models suggest relatively moderately rapid epidemic growth rates and doubling times, and a moderate expansion of DENV2 in Angola during the studied period. CONCLUSION: This study describes genomic, epidemiological and demographic characteristic of predominately urban transmission of DENV2 in Angola. We also find co-circulation of DENV2 with DENV1 and CHIKV and report several RT-PCR confirmed severe dengue cases in the country. Increasing dengue awareness in healthcare professional, expanding the monitorization of arboviral epidemics across the country, identifying most common mosquito breeding sites in urban settings, implementing innovative vector control interventions and dengue vaccination campaigns could help to reduce vector presence and DENV transmission in Angola.


Assuntos
Vírus da Dengue , Dengue , Dengue Grave , Angola/epidemiologia , Animais , Teorema de Bayes , Vírus da Dengue/genética , Surtos de Doenças , Genômica , Humanos , Mosquitos Vetores , Filogenia , RNA , Sorogrupo , Dengue Grave/epidemiologia
10.
Malar J ; 10: 22, 2011 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-21288345

RESUMO

BACKGROUND: Malaria is the major cause of morbidity and mortality in Angola. The most vulnerable groups to Plasmodium falciparum infection are pregnant women and children under five years of age. The use of an intermittent preventive treatment (IPT) with sulphadoxine/pyrimethamine (SP) in pregnant women was introduced in Angola in 2006 by the National Malaria Control Programme, and currently this strategy has been considered to be used for children malaria control. Considering the previous wide use of SP combination in Angola, together to the reported cases of SP treatment failure it is crucial the evaluation of the prevalence of five mutations in pfdhfr and pfdhps genes associated to P. falciparum resistance to SP before the introduction of S/P IPT in children. METHODS: The study was conducted in five provinces, with different transmission intensities: Huambo, Cabinda, Uíge, Kwanza Norte, and Malanje. The detection of the mutations in pfdhfr and pfdhps genes was carried out in 452 P. falciparum blood samples by PCR RFLP. RESULTS: For pfdhfr gene, 90,3% of the samples carried the mutation 51I, with 7.5% of mixed infections; 51% carried wild type allele 59C, with 29.2% mixed infections and; 99.1% of isolates harboured the mutant allele 108N. Concerning, pfdhps gene, 83,1% were mutant type 437G with 11% mixed infections , while 87% of the studied isolates were wild type for codon 540. DISCUSSION: This is the first representative epidemiological study of the whole Angola country on the prevalence of the genotypes associated with SP chemoresistance. A high frequency of individual mutations in both genes (51I and 108N in pfdhfr, and 437G in pfdhps) was found, besides a low prevalence of the quintuple mutation. CONCLUSION: The data showed that the implementation IPT using SP in children needs to be reviewed.


Assuntos
Antimaláricos/farmacologia , Di-Hidropteroato Sintase/genética , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Pirimetamina/farmacologia , Sulfadoxina/farmacologia , Tetra-Hidrofolato Desidrogenase/genética , Angola/epidemiologia , Antimaláricos/uso terapêutico , Quimioprevenção , Pré-Escolar , Combinação de Medicamentos , Resistência a Múltiplos Medicamentos , Feminino , Genes de Protozoários , Genótipo , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Mutação , Gravidez , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico
11.
Mem Inst Oswaldo Cruz ; 106 Suppl 1: 142-58, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21881769

RESUMO

The isolation of bioactive compounds from medicinal plants, based on traditional use or ethnomedical data, is a highly promising potential approach for identifying new and effective antimalarial drug candidates. The purpose of this review was to create a compilation of the phytochemical studies on medicinal plants used to treat malaria in traditional medicine from the Community of Portuguese-Speaking Countries (CPSC): Angola, Brazil, Cape Verde, Guinea-Bissau, Mozambique and São Tomé and Príncipe. In addition, this review aimed to show that there are several medicinal plants popularly used in these countries for which few scientific studies are available. The primary approach compared the antimalarial activity of native species used in each country with its extracts, fractions and isolated substances. In this context, data shown here could be a tool to help researchers from these regions establish a scientific and technical network on the subject for the CPSC where malaria is a public health problem.


Assuntos
Antimaláricos/uso terapêutico , Malária/tratamento farmacológico , Medicina Tradicional , Fitoterapia/métodos , Plantas Medicinais/classificação , Angola , Antimaláricos/classificação , Antimaláricos/isolamento & purificação , Ilhas Atlânticas , Brasil , Cabo Verde , Guiné-Bissau , Humanos , Idioma , Moçambique
12.
PLoS One ; 16(3): e0249249, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33765102

RESUMO

This study aimed to investigate the characteristics related to SARS-CoV-2 in Luanda, Angola. A total of 622 individuals were screened for SARS-CoV-2 from January to September 2020. Chi-square and logistic regression were used to identify the relationship between sociodemographic characteristics and SARS-CoV-2. Of the 622 tested, 14.3% tested positive. The infection rate was the same for both genders (14.3%). Individuals ≥40 years old, from non-urbanized areas, and healthcare professionals had a higher frequency of infection. The risk of infection was very high in individuals ≥60 years old (AOR: 23.3, 95% CI: 4.83-112), in women (AOR: 1.24, 95% CI: 0.76-2.04), in Luanda (AOR: 7.40, 95% CI: 1.64-33.4), and healthcare professionals (AOR: 1.27, 95% CI: 0.60-2.71), whereas a low risk was observed in individuals from urbanized areas (AOR: 0.44, 95% CI: 0.26-0.75). Our results suggest that Angolan authorities should implement a greater effort in non-urbanized areas and among healthcare professionals since when these individuals presented any indication for a COVID-19 test, such as fever/cough/myalgia, they were more likely to test positive for SARS-CoV-2 than having some other cause for symptoms.


Assuntos
COVID-19/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angola , COVID-19/patologia , COVID-19/virologia , Teste para COVID-19 , Criança , Pré-Escolar , Estudos Transversais , Demografia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , SARS-CoV-2/isolamento & purificação , Adulto Jovem
14.
Pan Afr Med J ; 38: 402, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34381546

RESUMO

INTRODUCTION: accurate and timely laboratory diagnosis of yellow fever (YF) is critical to the Eliminate Yellow Fever Epidemics (EYE) strategy. Gavi, the Vaccine Alliance recognized the need to support and build capacity in the national and regional laboratories in the Global YF Laboratory Network (GYFLN) as part of this strategy. METHODS: to better understand current capacity, gaps and needs of the GYFLN laboratories in Africa, assessments were carried out in national and regional reference laboratories in the 25 African countries at high risk for YF outbreaks that were eligible for new financial support from Gavi. RESULTS: the assessments found that the GYFLN in Africa has high capacity but 21% of specimens were not tested due to lack of testing kits or reagents and approximately 50% of presumptive YF cases were not confirmed at the regional reference laboratory due to problems with shipping. CONCLUSION: the laboratory assessments helped to document the baseline capacities of these laboratories prior to Gavi funding to support strengthening YF laboratories.


Assuntos
Surtos de Doenças , Laboratórios/estatística & dados numéricos , Febre Amarela/diagnóstico , África/epidemiologia , Fortalecimento Institucional , Epidemias , Humanos , Febre Amarela/epidemiologia
15.
Malar J ; 9: 135, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20492669

RESUMO

BACKGROUND: Plasmodium falciparum, has developed resistance to many of the drugs in use. The recommended treatment policy is now to use drug combinations. The atovaquone-proguanil (AP) drug combination, is one of the treatment and prophylaxis options. Atovaquone (ATQ) exerts its action by inhibiting plasmodial mitochondria electron transport at the level of the cytochrome bc1 complex. Plasmodium falciparum in vitro resistance to ATQ has been associated with specific point mutations in the region spanning codons 271-284 of the cytochrome b gene. ATQ -resistant Plasmodium yoelii and Plasmodium berghei lines have been obtained and resistant lines have amino acid mutations in their CYT b protein sequences. Plasmodium chabaudi model for studying drug-responses and drug-resistance selection is a very useful rodent malaria model but no ATQ resistant parasites have been reported so far. The aim of this study was to determine the ATQ sensitivity of the P. chabaudi clones, to select a resistant parasite line and to perform genotypic characterization of the cytb gene of these clones. METHODS: To select for ATQ resistance, Plasmodium. chabaudi chabaudi clones were exposed to gradually increasing concentrations of ATQ during several consecutive passages in mice. Plasmodium chabaudi cytb gene was amplified and sequenced. RESULTS: ATQ resistance was selected from the clone AS-3CQ. In order to confirm whether an heritable genetic mutation underlies the response of AS-ATQ to ATQ, the stability of the drug resistance phenotype in this clone was evaluated by measuring drug responses after (i) multiple blood passages in the absence of the drug, (ii) freeze/thawing of parasites in liquid nitrogen and (iii) transmission through a mosquito host, Anopheles stephensi. ATQ resistance phenotype of the drug-selected parasite clone kept unaltered. Therefore, ATQ resistance in clone AS-ATQ is genetically encoded. The Minimum Curative Dose of AS-ATQ showed a six-fold increase in MCD to ATQ relative to AS-3CQ. CONCLUSIONS: A mutation was found on the P. chabaudi cytb gene from the AS-ATQ sample a substitution at the residue Tyr268 for an Asn, this mutation is homologous to the one found in P. falciparum isolates resistant to ATQ.


Assuntos
Antimaláricos/farmacologia , Atovaquona/farmacologia , Citocromos b/genética , Resistência a Medicamentos , Plasmodium chabaudi/efeitos dos fármacos , Animais , Antimaláricos/uso terapêutico , Atovaquona/uso terapêutico , DNA de Protozoário/genética , Feminino , Genótipo , Malária/tratamento farmacológico , Malária/genética , Malária/parasitologia , Camundongos , Testes de Sensibilidade Parasitária , Plasmodium chabaudi/genética , Plasmodium chabaudi/isolamento & purificação , Mutação Puntual
16.
Nat Microbiol ; 5(3): 443-454, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31932713

RESUMO

Metagenomic next-generation sequencing (mNGS), the shotgun sequencing of RNA and DNA from clinical samples, has proved useful for broad-spectrum pathogen detection and the genomic surveillance of viral outbreaks. An additional target enrichment step is generally needed for high-sensitivity pathogen identification in low-titre infections, yet available methods using PCR or capture probes can be limited by high cost, narrow scope of detection, lengthy protocols and/or cross-contamination. Here, we developed metagenomic sequencing with spiked primer enrichment (MSSPE), a method for enriching targeted RNA viral sequences while simultaneously retaining metagenomic sensitivity for other pathogens. We evaluated MSSPE for 14 different viruses, yielding a median tenfold enrichment and mean 47% (±16%) increase in the breadth of genome coverage over mNGS alone. Virus detection using MSSPE arboviral or haemorrhagic fever viral panels was comparable in sensitivity to specific PCR, demonstrating 95% accuracy for the detection of Zika, Ebola, dengue, chikungunya and yellow fever viruses in plasma samples from infected patients. Notably, sequences from re-emerging and/or co-infecting viruses that have not been specifically targeted a priori, including Powassan and Usutu, were successfully enriched using MSSPE. MSSPE is simple, low cost, fast and deployable on either benchtop or portable nanopore sequencers, making this method directly applicable for diagnostic laboratory and field use.


Assuntos
Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Metagenoma , Metagenômica/métodos , Vírus/genética , Vírus/isolamento & purificação , Vírus Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , Biologia Computacional , DNA Viral/genética , Dengue/diagnóstico , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Ebolavirus/genética , Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/diagnóstico , Humanos , Reação em Cadeia da Polimerase , RNA Viral/genética , RNA Viral/isolamento & purificação , Viroses/diagnóstico , Febre Amarela/diagnóstico , Zika virus/genética , Infecção por Zika virus/diagnóstico
18.
PLoS One ; 14(11): e0225251, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31770425

RESUMO

Monitoring genetic diversity and drug resistance mutations (DRMs) is critical for understanding HIV epidemiology. Here, we report HIV-1 genetic diversity and DRMs in blood samples from 42 HIV-positive pregnant women naive to antiretroviral therapy (ART), in Luanda. The samples were subjected to nested-PCR, followed by sequencing of HIV-1 pol gene, targeting the protease and reverse transcriptase fragments. HIV-1 diversity was analyzed using the REGA HIV-1 subtyping tool and DRMs were identified using the Calibrated Population Resistance tool. A total of 34 sequences were obtained. The data revealed wide HIV-1 subtypes heterogeneity, with subtype C (38%, 13/34) the most frequent, followed by the subtypes F1 (18%, 6/34), A1 (9%, 3/34), G (9%, 3/34), D (6%, 2/34) and H (3%, 1/34). In addition, recombinants strains were detected, with CRF02_AG (6%, 2/34) the most frequent, followed by CRF37_cpx, F1/C, A1/G and H/G, all with 3% (1/34). A total of 6/34 (18%) of the sequences presented DRMs. The non-nucleoside reverse transcriptase inhibitors presented 15% (5/34) of resistance. Moreover, 1/34 (3%) sequence presented resistance against both non-nucleoside reverse transcriptase inhibitors and nucleoside reverse transcriptase inhibitors, simultaneously. Despite the small sample size, our results suggest the need to update currently used ART regimens. Surveillance of HIV-1 subtypes and DRMs are necessary to understand HIV epidemiology and to guide modification of ART guidelines in Angola.


Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral , Infecções por HIV/diagnóstico , HIV-1/genética , Complicações Infecciosas na Gravidez/virologia , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética , Adolescente , Adulto , Angola , Estudos Transversais , Feminino , Variação Genética , Técnicas de Genotipagem , HIV-1/classificação , HIV-1/efeitos dos fármacos , Humanos , Filogenia , Vigilância da População , Gravidez , Tamanho da Amostra , Análise de Sequência de RNA/métodos , Adulto Jovem
19.
Lancet Infect Dis ; 19(10): 1138-1147, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31559967

RESUMO

BACKGROUND: Zika virus infections and suspected microcephaly cases have been reported in Angola since late 2016, but no data are available about the origins, epidemiology, and diversity of the virus. We aimed to investigate the emergence and circulation of Zika virus in Angola. METHODS: Diagnostic samples collected by the Angolan Ministry of Health as part of routine arboviral surveillance were tested by real-time reverse transcription PCR by the Instituto Nacional de Investigação em Saúde (Ministry of Health, Luanda, Angola). To identify further samples positive for Zika virus and appropriate for genomic sequencing, we also tested samples from a 2017 study of people with HIV in Luanda. Portable sequencing was used to generate Angolan Zika virus genome sequences from three people positive for Zika virus infection by real-time reverse transcription PCR, including one neonate with microcephaly. Genetic and mobility data were analysed to investigate the date of introduction and geographical origin of Zika virus in Angola. Brain CT and MRI, and serological assays were done on a child with microcephaly to confirm microcephaly and assess previous Zika virus infection. FINDINGS: Serum samples from 54 people with suspected acute Zika virus infection, 76 infants with suspected microcephaly, 24 mothers of infants with suspected microcephaly, 336 patients with suspected dengue virus or chikungunya virus infection, and 349 samples from the HIV study were tested by real-time reverse transcription PCR. Four cases identified between December, 2016, and June, 2017, tested positive for Zika virus. Analyses of viral genomic and human mobility data suggest that Zika virus was probably introduced to Angola from Brazil between July, 2015, and June, 2016. This introduction probably initiated local circulation of Zika virus in Angola that continued until at least June, 2017. The infant with microcephaly in whom CT and MRI were done had brain abnormalities consistent with congenital Zika syndrome and serological evidence for Zika virus infection. INTERPRETATION: Our analyses show that autochthonous transmission of the Asian lineage of Zika virus has taken place in Africa. Zika virus surveillance and surveillance of associated cases of microcephaly throughout the continent is crucial. FUNDING: Royal Society, Wellcome Trust, Global Challenges Research Fund (UK Research and Innovation), Africa Oxford, John Fell Fund, Oxford Martin School, European Research Council, Departamento de Ciência e Tecnologia/Ministério da Saúde/National Council for Scientific and Technological Development, and Ministério da Educação/Coordenação de Aperfeicoamento de Pessoal de Nível Superior.


Assuntos
Surtos de Doenças , Transmissão Vertical de Doenças Infecciosas , Filogenia , Complicações Infecciosas na Gravidez/virologia , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/transmissão , Zika virus/genética , Angola/epidemiologia , Sequência de Bases , Feminino , Genoma Viral/genética , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Microcefalia/sangue , Microcefalia/etiologia , Microcefalia/virologia , Mães , Gravidez , RNA Viral/genética , Infecção por Zika virus/complicações , Infecção por Zika virus/virologia
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