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1.
Front Microbiol ; 14: 1190133, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37333655

RESUMEN

The overall pattern of the SARS-CoV-2 pandemic so far has been a series of waves; surges in new cases followed by declines. The appearance of novel mutations and variants underlie the rises in infections, making surveillance of SARS-CoV-2 mutations and prediction of variant evolution of utmost importance. In this study, we sequenced 320 SARS-CoV-2 viral genomes isolated from patients from the outpatient COVID-19 clinic in the Children's Cancer Hospital Egypt 57357 (CCHE 57357) and the Egypt Center for Research and Regenerative Medicine (ECRRM). The samples were collected between March and December 2021, covering the third and fourth waves of the pandemic. The third wave was found to be dominated by Nextclade 20D in our samples, with a small number of alpha variants. The delta variant was found to dominate the fourth wave samples, with the appearance of omicron variants late in 2021. Phylogenetic analysis reveals that the omicron variants are closest genetically to early pandemic variants. Mutation analysis shows SNPs, stop codon mutation gain, and deletion/insertion mutations, with distinct patterns of mutations governed by Nextclade or WHO variant. Finally, we observed a large number of highly correlated mutations, and some negatively correlated mutations, and identified a general inclination toward mutations that lead to enhanced thermodynamic stability of the spike protein. Overall, this study contributes genetic and phylogenetic data, as well as provides insights into SARS-CoV-2 viral evolution that may eventually help in the prediction of evolving mutations for better vaccine development and drug targets.

2.
Sci Rep ; 12(1): 14511, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-36008511

RESUMEN

A serious global public health emergency emerged late November 2019 in Wuhan City, China, by a new highly pathogenic virus, SARS-CoV-2. The virus evolution spread has been tracked by three developing databases: GISAID, Nextstrain and PANGO to understand its circulating variants. In this study, 110 diagnosed positive COVID-19 patient's samples, were collected from Kasr Al-Aini Hospital and the Children Cancer Hospital Egypt 57357 between May 2020 and January 2021, with clinical severity ranging from mild to severe. The viral genomes were sequenced by next generation sequencing, and phylogenetic analysis was performed to understand viral transmission dynamics. According to Nextstrain clades, most of our sequenced samples belonged to clades 20A and 20D, which in addition to clade 20B were present from the beginning of sample collection in May 2020. Clades 19A and 19B, on the other hand, appeared in the mid and late 2020 respectively, followed by the disappearance of clade 20B at the end of 2020. We identified a relatively high prevalence of the D614G spike protein variant and novel patterns of mutations associated together and with different clades. We also identified four mutations, spike H49Y, ORF3a H78Y, ORF8 E64stop and nucleocapsid E378V, associated with higher disease severity. Altogether, our study contributes genetic, phylogenetic, and clinical correlation data about the spread of the SARS-CoV-2 pandemic in Egypt.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , COVID-19/genética , Niño , Egipto/epidemiología , Genoma Viral , Humanos , Mutación , Pandemias , Filogenia , SARS-CoV-2/genética
3.
mSphere ; 6(6): e0072521, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34787450

RESUMEN

Infection by multidrug-resistant (MDR) Acinetobacter baumannii is one of the major causes of hospital-acquired infections worldwide. The ability of A. baumannii to survive in adverse conditions as well as its extensive antimicrobial resistance make it one of the most difficult to treat pathogens associated with high mortality rates. The aim of this study was to investigate MDR A. baumannii that has spread among pediatric cancer patients in the Children's Cancer Hospital Egypt 57357. Whole-genome sequencing was used to characterize 31 MDR A. baumannii clinical isolates. Phenotypically, the isolates were MDR, with four isolates showing resistance to the last-resort antibiotic colistin. Multilocus sequence typing showed the presence of eight clonal groups, two of which were previously reported to cause outbreaks in Egypt, and one novel sequence type (ST), Oxf-ST2246. Identification of the circulating plasmids showed the presence of two plasmid lineages in the isolates, strongly governed by sequence type. A large number of antimicrobial genes with a range of resistance mechanisms were detected in the isolates, including ß-lactamases and antibiotic efflux pumps. Analysis of insertion sequences (ISs) revealed the presence of ISAba1 and ISAba125 in all the samples, which amplify ß-lactamase expression, causing extensive carbapenem resistance. Mutation analysis was used to decipher underlying mutations responsible for colistin resistance and revealed novel mutations in several outer membrane proteins, in addition to previously reported mutations in pmrB. Altogether, understanding the transmissibility of A. baumannii as well as its resistance and virulence mechanisms will help develop novel treatment options for better management of hospital-acquired infections. IMPORTANCE Acinetobacter baumannii represents a major health threat, in particular among immunocompromised cancer patients. The rise in carbapenem-resistant A. baumannii, and the development of resistance to the last-resort antimicrobial agent colistin, complicates the management of A. baumannii outbreaks and increases mortality rates. Here, we investigate 31 multidrug resistant A. baumannii isolates from pediatric cancer patients in Children's Cancer Hospital Egypt (CCHE) 57357 via whole-genome sequencing. Multilocus sequence typing (MLST) showed the presence of eight clonal groups including a novel sequence type. In silico detection of antimicrobial-resistant genes and virulence factors revealed a strong correlation between certain virulence genes and mortality as well as several point mutations in outer membrane proteins contributing to colistin resistance. Detection of CRISPR/Cas sequences in the majority of the samples was strongly correlated with the presence of prophage sequences and associated with failure of bacteriophage therapy. Altogether, understanding the genetic makeup of circulating A. baumannii is essential for better management of outbreaks.


Asunto(s)
Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/genética , Acinetobacter baumannii/aislamiento & purificación , Farmacorresistencia Bacteriana Múltiple/genética , Tipificación de Secuencias Multilocus , Infecciones por Acinetobacter/epidemiología , Infecciones por Acinetobacter/transmisión , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/patogenicidad , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Instituciones Oncológicas , Carbapenémicos/farmacología , Colistina/farmacología , Infección Hospitalaria , Egipto , Hospitales Pediátricos , Humanos , Pruebas de Sensibilidad Microbiana , Secuenciación Completa del Genoma , beta-Lactamasas/genética
4.
Asian Pac J Trop Med ; 10(10): 996-1001, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29111196

RESUMEN

OBJECTIVE: To investigate molecular and serological prevalence of Toxoplasma gondii (T. gondii) in pregnant women and sheep in Egypt. METHODS: Blood samples collected from healthy 364 pregnant women and 170 sheep were investigated for T. gondii antibodies and parasitemia using highly specific and sensitive surface antigen (TgSAG2) based enzyme linked immunosorbent assay (ELISA) and real time-polymerase chain reaction (RT-PCR). RESULTS: Overall prevalence of T. gondii was 51.76%, 17.65% in sheep, 33.79%, 11.81% in pregnant women, using ELISA and RT-PCR respectively. Significant differences in T. gondii prevalence were observed on the basis of contact with cats or soil in pregnant women using either RT-PCR or ELISA. In pregnant women, a significant increase was detected in aged and those eating under-cooked mutton using simultaneous ELISA/RT-PCR. CONCLUSIONS: Consumption of under-cooked infected mutton is an important source of human infection and the combination of the two assays provide accurate and precise data during infection.

5.
J Egypt Soc Parasitol ; 47(1): 93-100, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30157336

RESUMEN

Protozoan parasite Toxoplasma gondii is considered as one of the most critical risk factor for recurrent abortion in pregnant females and resulted in multi congenital malformation in fetus world-wide. The present study was carried out on 693 pregnant females from Alexandria, Beheira, Gharbia, Menoufia, Qalyoubia and Fayoum provinces,"The study determined the prevalence of toxoplasmosis in pregnant females during pregnancy trimesters and shed the lights on the main risk factors and possible contamination routes. Detection for the presence of Toxoplasma IgG antibodies were done by enzyme linked fluorescence assay (ELFA). It was found that the overall seroprevalence of T. gondii was 30.16%.The seroprevalence increased with age. Significant relations were observed between Toxoplasma IgG antibodies and abortion history, maternity trimester and consumption of under-cooked meat. No significant differences were reported due to parity, occupation, abortion trimester, contact with cats and/or other animals and exposure to soil.


Asunto(s)
Infecciones Asintomáticas/epidemiología , Complicaciones Parasitarias del Embarazo/epidemiología , Toxoplasmosis/epidemiología , Adulto , Factores de Edad , Animales , Anticuerpos Antiprotozoarios/sangre , Gatos , Ingestión de Alimentos , Egipto/epidemiología , Femenino , Humanos , Carne/parasitología , Ocupaciones , Embarazo , Complicaciones Parasitarias del Embarazo/etiología , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Factores de Riesgo , Estudios Seroepidemiológicos , Toxoplasma/inmunología , Toxoplasmosis/embriología , Toxoplasmosis/etiología , Adulto Joven
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