Subregional origins of emerging SARS-CoV-2 variants during the second pandemic wave in Côte d'Ivoire.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with increased transmissibility, virulence and immune escape abilities have heavily altered the COVID-19 pandemic's course. Deciphering local and global transmission patterns of those variants is thus key in building a profound understanding of the virus' spread around the globe. In the present study, we investigate SARS-CoV-2 variant epidemiology in Côte d'Ivoire, Western sub-Saharan Africa. We therefore generated 234 full SARS-CoV-2 genomes stemming from Central and Northern Côte d'Ivoire. Covering the first and second pandemic wave the country had been facing, we identified 20 viral lineages and showed that in Côte d'Ivoire the second pandemic wave in 2021 was driven by the spread of the Alpha (B.1.1.7) and Eta (B.1.525) variant. Our analyses are consistent with a limited number of international introductions of Alpha and Eta into Côte d'Ivoire, and those introduction events mostly stemmed from within the West African subregion. This suggests that subregional travel to Côte d'Ivoire had more impact on local pandemic waves than direct intercontinental travel.

Multicountry study of SARS-CoV-2 and associated risk factors among healthcare workers in Côte d'Ivoire, Burkina Faso and South Africa.

BACKGROUND: Reports on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread across Africa have varied, including among healthcare workers (HCWs). This study assessed the comparative SARS-CoV-2 burden and associated risk factors among HCWs in three African countries. METHODS: A multicentre study was conducted at regional healthcare facilities in Côte d'Ivoire (CIV), Burkina Faso (BF) and South Africa (SA) from February to May 2021. HCWs provided blood samples for SARS-CoV-2 serology and nasopharyngeal/oropharyngeal swabs for testing of acute infection by polymerase chain reaction and completed a questionnaire. Factors associated with seropositivity were assessed with logistic regression. RESULTS: Among 719 HCWs, SARS-CoV-2 seroprevalence was 34.6% (95% confidence interval 31.2 to 38.2), ranging from 19.2% in CIV to 45.7% in BF. A total of 20 of 523 (3.8%) were positive for acute SARS-CoV-2 infection. Female HCWs had higher odds of SARS-CoV-2 seropositivity compared with males, and nursing staff, allied health professionals, non-caregiver personnel and administration had higher odds compared with physicians. HCWs also reported infection prevention and control (IPC) gaps, including 38.7% and 29% having access to respirators and IPC training, respectively, in the last year. CONCLUSIONS: This study was a unique comparative HCW SARS-CoV-2 investigation in Africa. Seroprevalence estimates varied, highlighting distinctive population/facility-level factors affecting COVID-19 burden and the importance of established IPC programmes to protect HCWs and patients.

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.

Investment in Africa over the past year with regards to SARS-CoV-2 genotyping has led to a massive increase in the number of sequences, exceeding 100,000 genomes generated to track the pandemic on the continent. Our results show an increase in the number of African countries able to sequence within their own borders, coupled with a decrease in sequencing turnaround time. Findings from this genomic surveillance underscores the heterogeneous nature of the pandemic but we observe repeated dissemination of SARS-CoV-2 variants within the continent. Sustained investment for genomic surveillance in Africa is needed as the virus continues to evolve, particularly in the low vaccination landscape. These investments are very crucial for preparedness and response for future pathogen outbreaks. One-Sentence SummaryExpanding Africa SARS-CoV-2 sequencing capacity in a fast evolving pandemic.

A year of genomic surveillance reveals how the SARS-CoV-2 pandemic unfolded in Africa

The progression of the SARS-CoV-2 pandemic in Africa has so far been heterogeneous and the full impact is not yet well understood. Here, we describe the genomic epidemiology using a dataset of 8746 genomes from 33 African countries and two overseas territories. We show that the epidemics in most countries were initiated by importations, predominantly from Europe, which diminished following the early introduction of international travel restrictions. As the pandemic progressed, ongoing transmission in many countries and increasing mobility led to the emergence and spread within the continent of many variants of concern and interest, such as B.1.351, B.1.525, A.23.1 and C.1.1. Although distorted by low sampling numbers and blind-spots, the findings highlight that Africa must not be left behind in the global pandemic response, otherwise it could become a breeding ground for new variants.

First Evidence of Shape Coexistence in the

The N=48 ^{80}Ge nucleus is studied by means of ß-delayed electron-conversion spectroscopy at ALTO. The radioactive ^{80}Ga beam is produced through the isotope separation on line photofission technique and collected on a movable tape for the measurement of γ and e^{-} emission following ß decay. An electric monopole E0 transition, which points to a 639(1) keV intruder 0_{2}^{+} state, is observed for the first time. This new state is lower than the 2_{1}^{+} level in ^{80}Ge, and provides evidence of shape coexistence close to one of the most neutron-rich doubly magic nuclei discovered so far, ^{78}Ni. This result is compared with theoretical estimates, helping to explain the role of monopole and quadrupole forces in the weakening of the N=50 gap at Z=32. The evolution of intruder 0_{2}^{+} states towards ^{78}Ni is discussed.

Measurement of the neutron radius of 208Pb through parity violation in electron scattering.

We report the first measurement of the parity-violating asymmetry A(PV) in the elastic scattering of polarized electrons from 208Pb. A(PV) is sensitive to the radius of the neutron distribution (R(n)). The result A(PV)=0.656±0.060(stat)±0.014(syst) ppm corresponds to a difference between the radii of the neutron and proton distributions R(n)-R(p)=0.33(-0.18)(+0.16) fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.