Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Afr J Infect Dis ; 18(1): 1-4, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38058416

RESUMO

Background: In Madagascar, no study has reported the impact of COVID-19 on people living with HIV (PLHIV). The present work aimed to analyze the seroprevalence of SARS-CoV-2 in Malagasy PLHIV before and during the three waves of COVID-19 pandemic.This is a retrospective study. Materials and Methods: We conducted a retrospective serological survey in PLHIV followed up for HIV viral load (VL) monitoring at the Centre d'Infectiologie Charles Mérieux Madagascar (CICM) between June 2019 and April 2022. The presence of IgM and/or IgG antibodies against SARS-CoV-2 nucleoprotein was detected using a rapid diagnostic test (COVID-PRESTO®). Results: A seroprevalence of 2.5% was found in the 877 patients tested before March 2020, compared to 25.4% (512/2,011) between March 2020 and April 2022. This seroprevalence was 21.7%, 22.3% and 60.1% after the first, second and third waves of COVID-19, respectively. We observed a marginally significant difference (p = 0.043) in SARS-CoV-2 seroprevalence between patients on highly active antiretroviral therapy (HAART) (27.5%) and those who were not (23.7%). No statistically significant difference was observed between PLHIV with undetectable HIV VL (27.4%) and the different detectable VL categories (p>0.05). Conclusions: Our data show the presence of antibodies to SARS-CoV-2 among PLHIV as early as December 2019 in Madagascar. At least 25.4% (512/2,011) of Malagasy PLHIV have been in contact with SARS-CoV-2 since March 2020. There is no significant relation between HIV-1 VL and SARS-CoV-2 seroprevalence. Additional studies with more robust assays in the general population are needed for a detailed knowledge of SARS-CoV-2 impact in Madagascar.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22274330

RESUMO

BackgroundMany SARS-CoV-2 seroprevalence surveys since the end of 2020 have disqualified the first misconception that Africa had been spared by the pandemic. Through the analysis of three SARS-CoV-2 seroprevalence surveys carried out in Benin as part of the ARIACOV project, we argue that the integration of epidemiological serosurveillance of the SARS-COV2 infection in the national surveillance package would be of great use to refine the understanding of the COVID-19 pandemic in Africa. MethodsThree repeated cross-sectional surveys have been carried out in Benin, two in Cotonou, the economic capital in March and May 2021, and one in Natitingou, a semi-rural city in North in August 2021. The global and by age-groups weighted seroprevalences have been estimated and the risk factors of the infection by SARS-COV-2 have been assessed by using logistic regression. ResultsIn Cotonou, a slight increase in overall age-standardized SARS-CoV-2 seroprevalence from 29.77% (95% CI: 23.12-37.41%) at the first survey to 34.86% (95% CI: 31.57-38.30%) at the second survey was observed. In Natitingou the global adjusted seroprevalence was 33.34% (95% CI: 27.75-39.44%), much higher than expected. Adults over 40 seemed to be more at risk than the youngest during the first survey in Cotonou but no longer in the second survey, showing the persistence of the SARS-COV-2 virus circulation outside the epidemic waves. ConclusionsA routine serological surveillance on strategic sentinel sites and / or populations could constitute a cost / effective compromise to better anticipate the onset of new waves and define public health strategies.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21256637

RESUMO

Many high-income countries have met the SARS-CoV-2 pandemic with overwhelming sequencing resources and have identified numerous distinct lineages, including some with notably altered biology. Over a year into the pandemic following unprecedented reductions in worldwide human mobility, distinct introduced lineages of SARS-CoV-2 without sequenced antecedents are increasingly discovered in high-income countries as a result of ongoing SARS-CoV-2 genomic surveillance initiatives. We here describe one such SARS-CoV-2 lineage, carrying many mutations and deletions in the spike protein shared with widespread variants of concern (VOCs), including E484K, S477N and deletions HV69{Delta}, Y144{Delta}, and LLA241/243{Delta}. This lineage - designated B.1.620 - is known to circulate in Lithuania and has now been found in several European states, but also in increasing numbers in central Africa owing to important recent increases in genome sequencing efforts on the continent. We provide evidence of likely ongoing local transmission of B.1.620 in Lithuania, France, Germany, Spain, Belgium and the Central African Republic. We describe the suite of mutations this lineage carries, its potential to be resistant to neutralising antibodies, travel histories for a subset of the European cases, and evidence of local B.1.620 transmission in Europe. We make a case for the likely Central African origin of this lineage by providing travel records as well as the outcomes of carefully crafted phylogenetic and phylogeographic inference methodologies, the latter of which is able to exploit individual travel histories recorded for infected travellers having entered different European countries.

4.
Ecohealth ; 14(1): 100-114, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28050688

RESUMO

Like the majority of emerging infectious diseases, HIV and HTLV are of zoonotic origin. Here we assess the risk of cross-species transmissions of their simian counterparts, SIV and STLV, from non-human primates (NHP) to humans in the Democratic Republic of Congo (DRC). A total of 331 samples, derived from NHP bushmeat, were collected as dried blood spots (DBS, n = 283) or as tissue samples (n = 36) at remote forest sites mainly in northern and eastern DRC. SIV antibody prevalences in DBS were estimated with a novel high throughput immunoassay with antigens representing the actual known diversity of HIV/SIV lineages. Antibody-positive samples were confirmed by PCR and sequence analysis. Screening for STLV infection was done with universal primers in tax, and new strains were further characterized in LTR. SIV and STLV infection in tissue samples was done by PCR only. Overall, 5 and 15.4% of NHP bushmeat was infected with SIV and STLV, respectively. A new SIV lineage was identified in Allen's swamp monkeys (Allenopithecus nigroviridis). Three new STLV-1 subtypes were identified in Allen's swamp monkeys (Allenopithecus nigroviridis), blue monkeys (Cercopithecus mitis), red-tailed guenons (Cercopithecus ascanius schmidti) and agile mangabeys (Cercocebus agilis). SIV and STLV prevalences varied according to species and geographic region. Our study illustrates clearly, even on a small sample size from a limited number of geographic areas, that our knowledge on the genetic diversity and geographic distribution of simian retroviruses is still limited and that humans continue to be exposed to relative high proportions on infected NHP bushmeat.


Assuntos
Primatas/virologia , Retrovirus dos Símios/genética , Retrovirus dos Símios/isolamento & purificação , Animais , Anticorpos Antivirais/sangue , Infecções por Deltaretrovirus/diagnóstico , Infecções por Deltaretrovirus/transmissão , República Democrática do Congo , Variação Genética , Humanos , Carne , Filogenia , Prevalência , Retrovirus dos Símios/classificação , Síndrome de Imunodeficiência Adquirida dos Símios/diagnóstico , Síndrome de Imunodeficiência Adquirida dos Símios/transmissão , Zoonoses/transmissão , Zoonoses/virologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...