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2.
Science ; 378(6623): eadd8737, 2022 12 02.
Article in English | MEDLINE | ID: mdl-36454863

ABSTRACT

The geographic and evolutionary origins of the SARS-CoV-2 Omicron variant (BA.1), which was first detected mid-November 2021 in Southern Africa, remain unknown. We tested 13,097 COVID-19 patients sampled between mid-2021 to early 2022 from 22 African countries for BA.1 by real-time RT-PCR. By November-December 2021, BA.1 had replaced the Delta variant in all African sub-regions following a South-North gradient, with a peak Rt of 4.1. Polymerase chain reaction and near-full genome sequencing data revealed genetically diverse Omicron ancestors already existed across Africa by August 2021. Mutations, altering viral tropism, replication and immune escape, gradually accumulated in the spike gene. Omicron ancestors were therefore present in several African countries months before Omicron dominated transmission. These data also indicate that travel bans are ineffective in the face of undetected and widespread infection.

3.
Gastrointest Tumors ; 6(3-4): 122-136, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31768356

ABSTRACT

Hepatocellular carcinoma (HCC) represents a worrying public health problem in North Africa and particularly in Egypt. The situation is unclear in western North Africa where HCC has been rarely submitted to careful scrutiny. We decided to analyze demographic, biochemical, virological, and clinical data of a series of HCC from Algerian patients to establish the landscape of this tumor in the country. In the present work, we described 337 cases of primary liver cancer from Bologhine Hospital in Algiers, the capital of Algeria. The mean age of patients was 63.8 ± 11.4 years with a male:female sex ratio of 1.5. The most prevalent risk factors were hepatitis C, hepatitis B, and metabolic pathologies (type 2 diabetes and obesity). The mean BMI was 25.6 ± 4.7 at tumor diagnosis. A strong duality of risk factors and tumor presentation between male and female patients was apparent. Women tended to be older (mean 65.4 vs. 62.7 years, p = 0.039) and either seropositive for anti-HCV (60.0 vs. 41.6%, p = 0.0018) resulting primarily from tattoos and/or scarification (47.2 vs. 25.7%, p = 1.0 × 10-4) or more often affected by metabolic disorders (mean BMI 26.1 ± 0.7 vs. 25.1 ± 0.5, p = 0.0248) commonly associated with personal antecedents of cholecystectomy (21.2 vs. 5.8%, p = 4.4 × 10-5). By contrast, men were younger, poorer survivors (mean 9.3 vs. 13.3 months, p = 0.005), more frequently HBsAg carriers (27.8 vs. 10.5%, p = 4.8 × 10-5), and more exposed to lifestyle risk factors such as smoking (39.4 vs. 3.0%, p = 3.9 × 10-16) or alcohol use (19.1 vs. 0.7%, 1.5 × 10-8). Finally, geographic disparities throughout Algeria were reminiscent of the situation of chronic hepatitis C in the country. A significant excess of cases originated from the region of Batna, Eastern Algeria, already known for its high rate of hepatitis C. Our results suggest that due to culture or sex-dependent biological differences, the tumor process affecting the liver is drastically different between sexes in Algeria.

4.
Arch Virol ; 162(6): 1641-1648, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28236070

ABSTRACT

Algeria is the largest country of Africa, with a population of 40 million inhabitants living in disparate environments from the Sahara to the large cities of the Mediterranean coast. The molecular epidemiology of hepatitis B virus (HBV) variants has been partially described, but variations in the seroprevalence of HBV surface antigen (HBsAg) throughout the Algerian territories are still poorly described. We analyzed demographic features of new cases of chronic infection collected in 41 administrative regions (covering 92% of the population) in 2013. The mean age of the 1876 HBsAg(+) patients was 36.8 ± 14.2 years, with a slight excess of males (54%). The seroprevalence of HBV early antigen (HBeAg) was 9.3%, and the mean virus load was 3.2 ± 1.8 log IU/ml. A subset of 15.2% of patients was already cirrhotic at disease discovery. An important heterogeneity was observed throughout the country, with nine regions displaying a significant excess of cases. These regions formed four distinct foci located in distant parts of the country: Adrar-Bechar (southwest), El-Oued-Tebessa (east), M'Sila-Sétif (north central) and Oran-Aïn Temouchent (northwest). An excess of cases was found as well in the national capital Algiers. Patients from southern regions with an excess of cases (Bechar, Adrar, El Oued) were significantly younger (32.0 ± 10.7 years), as were patients from the regions of Bejaia and Bouira (32.1 ± 10.6). The southwestern regions were also marked by a significant imbalance of the sex ratio (58 vs 39% of female cases, P = 4.5 E-5). The highest HBeAg seroprevalence was observed in Setif (26.4 vs. 7.6%, OR = 4.3, 95% CI 2.6-6.5, P = 1.1 × 10-11) in accordance with the higher virus loads observed in the patients (3.9 ± 2.3 vs. 3.1 ± 1.6, P = 0.0002). In conclusion, we observed heterogeneity in HBsAg seroprevalence, demographic traits, and disease evolution in Algeria. Further studies are now warranted to shed light on these differences, which are presumably due to variability in transmission routes or in the infectivity of viral isolates.


Subject(s)
Hepatitis B Surface Antigens/blood , Hepatitis B e Antigens/blood , Hepatitis B virus/isolation & purification , Hepatitis B, Chronic/epidemiology , Adult , Algeria/epidemiology , DNA, Viral/blood , Female , Geography , Hepatitis B Surface Antigens/immunology , Hepatitis B e Antigens/immunology , Hepatitis B virus/genetics , Hepatitis B virus/immunology , Hepatitis B, Chronic/immunology , Hepatitis B, Chronic/virology , Humans , Male , Middle Aged , Real-Time Polymerase Chain Reaction , Seroepidemiologic Studies , Serologic Tests , Viral Load , Young Adult
5.
J Med Virol ; 88(8): 1394-403, 2016 08.
Article in English | MEDLINE | ID: mdl-26856380

ABSTRACT

Algeria is the largest country of Africa, peopled with populations living a range of traditional/rural and modern/urban lifestyles. The variations of prevalence of chronic active hepatitis care poorly known on the Algerian territory. We conducted a retrospective survey on all patients (n = 998) referred to our institution in 2012 and confirmed by us for an active hepatitis C. Half of the hepatitis C virus (HCV) isolates were genotyped. Forty Algerian regions out of the 48 were represented in our study. Three geographical clusters (Aïn-Temouchent/SidiBelAbbes, Algiers, and a large Eastern region) with an excess of active hepatitis C were observed. Patients coming from the Eastern cluster (Batna, Khenchela, Oum el Bouaghi, and Tebessa) were strongly over-represented (49% of cases, OR = 14.5, P < 0.0001). The hallmarks of Eastern region were an excess of women (65% vs. 46% in the remaining population, P < 0.0001) and the almost exclusive presence of HCV genotype 1 (93% vs. 63%, P = 0.0001). The core of the epidemics was apparently located in Khenchela (odds ratio = 24.6, P < 0.0001). This situation is plausibly connected with nosocomial transmission or traditional practices as scarification (Hijama), piercing or tattooing, very lively in this region. Distinct hepatitis C epidemics are currently affecting Algerian population. The most worrying situation is observed in rural regions located east of Algeria. J. Med. Virol. 88:1394-1403, 2016. © 2016 Wiley Periodicals, Inc.


Subject(s)
Cluster Analysis , Cross Infection/epidemiology , Hepacivirus/genetics , Hepatitis C/epidemiology , Hepatitis C/transmission , Adolescent , Adult , Aged , Aged, 80 and over , Algeria/epidemiology , Child , Cross Infection/virology , Female , Genotype , Hepacivirus/classification , Hepacivirus/isolation & purification , Hepatitis C/immunology , Hepatitis C/virology , Hepatitis C Antibodies/blood , Humans , Male , Middle Aged , Polymerase Chain Reaction , Prevalence , RNA, Viral/blood , Retrospective Studies , Risk Factors , Rural Population/trends , Surveys and Questionnaires , Young Adult
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