Bioinformatic analyses of kappa casein gene in mammalian livestock species

2020 ◽  
Vol 40 (2) ◽  
pp. 7-12
Author(s):  
A. S. Adenaike ◽  
S. O. Peters ◽  
A. O. Fafiolu ◽  
R. A. Lawal ◽  
M. Wheto ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Amino Acids ◽  
Nucleotide Diversity ◽  
Haplotype Diversity ◽  
Recent Common Ancestor ◽  
Comparative Genomic ◽  
Gene Sequences ◽  
Livestock Species ◽  
Percent Identity ◽  
Most Recent Common Ancestor

Kappa casein (CSN3) gene is a variant of the milk protein highly conserved in mammalian species. Genetic variations in CSN3 gene of six mammalian livestock species were investigated using bioinformatics approach. A total of twenty-seven CSN3 gene sequences with corresponding amino acids belonging to the six species studied were retrieved from GenBank. Using a comparative genomic approach, we obtained 1797 bp of the CSN3 sequences from cattle, goat, horse, pig, rabbit and sheep. Alignment of twenty-seven sequences within the region of 1713 bp and containing gaps was carried out using Clustal W. The sequence alignment revealed high polymorphisms of CSN3 sequences among the six species. The percent identity and similarity between species were determined by conducting pair-wise comparisons of the sequences. Results revealed high level of identity and similarity among the ruminant animals (84-97% and 86-99%) which implied the gene is conserved in all the ruminants. However, percent identity and similarity between pig and rabbit were relatively low (45%, 61%). This revealed that CSN3 protein from them might be functionally different and divergence between them is more ancient. Higher polymorphism of amino acids was observed among the species than within species. Four non-synonymous mutations occurred in cattle, six in goat, four in horse, three in rabbit and seven in sheep. The results of DnaSP analysis indicated that the selected region (1-1797 bp) of the twenty-seven sequences from all the species had 1298 nucleotide sites excluding sites with gaps (499). There are invariable and variable sites that include 185 singleton variable sites and 56 parsimony informative sites. The nucleotide diversity (ð= 0.212) and average number of nucleotide diversity (k = 94.84) for all sequences which were lower than the highest values in rabbit (ð = 0.557, k = 229) were estimated. Divergence of the species could be inferred from high genetic diversity of the CSN3 gene. The haplotype diversity was 1.00 in goat, horse and sheep indicating abundant genetic diversity in those species. Close relationship between goat and sheep was observed in phylogenetic tree of CSN3 gene which showed that the comparability of CSN3 gene sequences was highest between the goat and sheep and they evolved from a most recent common ancestor. A more detailed study involving more divergent taxa and complete amino acid sequence will help to delineate how the mutations affect the functions of the gene.

scholarly journals Short Communication: Genetic diversity and phylogenetic analysis of two Indonesian local cattle breeds based on cytochrome b gene sequences

2018 ◽  
Vol 20 (1) ◽  
pp. 17-22
Author(s):  
TETY HARTATIK ◽  
DWI NUR HAPPY HARIYONO ◽  
YUDI ADINATA
Keyword(s):  
Genetic Diversity ◽  
Phylogenetic Analysis ◽  
Cytochrome B ◽  
Nucleotide Diversity ◽  
Haplotype Diversity ◽  
Cytochrome B Gene ◽  
Cyt B ◽  
Gene Sequences ◽  
Cattle Breeds ◽  
Cyt B Gene

Hartatik T, Hariyono DNH, Adinata Y. 2019. Genetic diversity and phylogenetic analysis of two Indonesian local cattle breeds based on cytochrome b gene sequences. Biodiversitas 20: 17-22. Genetic diversity and phylogenetic relationships of two Indonesian local cattle breeds (Pasundan and Pacitan cattle) were investigated using mitochondrial DNA (mtDNA) cytochrome b (cyt b) gene analysis. Partial sequences of cyt b gene, 404 bp in length, were determined for 21 individuals from the two breeds. Genetic diversity of the breeds was assessed based on the number of polymorphic sites, number of haplotypes, haplotype diversity, nucleotide diversity and average number of differences. In addition, a neighbour-joining (NJ) haplotype tree was constructed based on Kimura’s two-parameter model. Among the two breeds, haplotype and nucleotide diversity of Pacitan cattle were the highest with values of 0.3778 and 0.00099, respectively. In contrast, Pasundan cattle had the lowest value for haplotype (0.1818) and nucleotide (0.00045) diversity. Four haplotypes (Hap_16, Hap_17, Hap_18 and Hap_19) were found across the two breeds and around 85.71% of investigated individuals were classified as Hap_16. Phylogenetic analysis with the inclusion of the cyt b sequences from 39 cattle breeds from Genbank database, showed that Indonesian cattle made a separated lineage together with Bos javanicus, B. bison, and B. bonasus. Pasundan and Pacitan cattle were considered from the same lineage based on haplotype distribution as well as phylogenetic analysis. This study may help the future researchers and livestock breeders for designing a breeding program based on a better understanding of the genetic diversity and history of local breeds.

scholarly journals Genetic diversity analysis and phylogenetic reconstruction of groupers Epinephelus spp. from Madura Island, Indonesia based on partial sequence of CO1 gene

2021 ◽  
Vol 22 (10) ◽  
Author(s):  
ABDUL BASITH ◽  
Abinawanto Abinawanto ◽  
ENI KUSRINI ◽  
YASMAN YASMAN
Keyword(s):  
Genetic Diversity ◽  
Phylogenetic Tree ◽  
Nucleotide Diversity ◽  
Haplotype Diversity ◽  
Phylogenetic Reconstruction ◽  
Partial Sequence ◽  
Diversity Analysis ◽  
Epinephelus Coioides ◽  
Substitution Model ◽  
Genetic Diversity Analysis

Abstract. Basith A, Abinawanto, Kusrini E, Yasman. 2021. Genetic diversity analysis and phylogenetic reconstruction of groupers Epinephelus spp. from Madura Island, Indonesia based on partial sequence of CO1 gene. Biodiversitas 22: 4282-4290. Groupers populations in Indonesia, particularly from Madura Island, East Java are indicated to be over-fished, thereby requiring data collection of more accurate genetic resources as an important step for grouper conservation. A total of 14 samples of the Epinepheplus groupers were obtained from the fish landing port on Madura Island. The 617 bp CO1 gene sequence was utilized for genetic diversity analysis and phylogenetic tree reconstruction. Genetic diversity is based on the value of haplotype diversity (Hd) and nucleotide diversity (?). Reconstruction of the phylogenetic tree includes neighbor-joining (NJ) implementing K2P substitution model, while maximum likelihood (ML) is conducted by implementing HKY+G+I substitution model, both of which were evaluated by employing a bootstrap of 1000 replications. Analysis of genetic distance between species indicated that the farthest distance between E. heniochus and E. fasciatus was 0.189, while the closest distance between E. erythrurus and E. ongus was 0.099. Intrapopulation genetic diversity indicated a high value with details of Hd=0.978 and ?=0.12107. Furthermore, NJ and ML phylogenetic tree demonstrated similar topology in the observed Epinephelus spp. obtained from Madura Island grouped into 7 clades, that is Epinephelus coioides, E. bleekeri, E. areolatus, E. erythrurus, E. heniochus, E. fasciatus, and E. ongus.

scholarly journals Evolution and Genetic Diversity of Porcine Circovirus 3 in China

Viruses ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 786 ◽  
Author(s):  
Ye Chen ◽  
Quanming Xu ◽  
Hong Chen ◽  
Xian Luo ◽  
Qi Wu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Eastern China ◽  
Porcine Circovirus ◽  
Recent Common Ancestor ◽  
Fujian Province ◽  
Tissue Samples ◽  
Genetic Characteristics ◽  
Most Recent Common Ancestor ◽  
Porcine Circovirus 3 ◽  
High Degree

The identification of a new circovirus (Porcine Circovirus 3, PCV3) has raised concern because its impact on swine health is not fully known. In Fujian Province in eastern China, even its circulating status and genetic characteristics are unclear. Here, we tested 127 tissue samples from swine from Fujian Province that presented respiratory symptoms. All of the PCV3 positive samples were negative for many other pathogens involved in respiratory diseases like PCV2, PRRSV, and CSFV, suggesting that PCV3 is potentially pathogenic. From phylogenetic analysis, PCV3 strains are divided into two main clades and five sub-clades; PCV3a-1, PCV3a-2, PCV3a-3, PCV3b-1, and PCV3b-2. Our identified strains belong to genotypes PCV3a-1, PCV3a-2, PCV3a-3, and PCV3b-2, indicating a high degree of genetic diversity of PCV3 in Fujian province until 2019. Interestingly, we found the time of the most recent common ancestor (tMRCA) of PCV3 was dated to the 1950s, and PCV3 has a similar evolutionary rate as PCV2 (the main epidemic genotypes PCV2b and PCV2d). In addition, positive selection sites N56D/S and S77T/N on the capsid gene are located on the PCV3 antigen epitope, indicating that PCV3 is gradually adaptive in swine. In summary, our results provide important insights into the epidemiology of PCV3.

scholarly journals How old are bacterial pathogens?

2016 ◽  
Vol 283 (1836) ◽  
pp. 20160990 ◽  
Author(s):  
Mark Achtman
Keyword(s):  
Genetic Diversity ◽  
Common Ancestor ◽  
Bacterial Pathogens ◽  
Recent Common Ancestor ◽  
Evolutionary Divergence ◽  
Bacterial Diseases ◽  
Most Recent Common Ancestor ◽  
Anatomically Modern Humans ◽  
H Pylori ◽  
Medical Bacteriology

Only few molecular studies have addressed the age of bacterial pathogens that infected humans before the beginnings of medical bacteriology, but these have provided dramatic insights. The global genetic diversity of Helicobacter pylori , which infects human stomachs, parallels that of its human host. The time to the most recent common ancestor (tMRCA) of these bacteria approximates that of anatomically modern humans, i.e. at least 100 000 years, after calibrating the evolutionary divergence within H. pylori against major ancient human migrations. Similarly, genomic reconstructions of Mycobacterium tuberculosis , the cause of tuberculosis, from ancient skeletons in South America and mummies in Hungary support estimates of less than 6000 years for the tMRCA of M. tuberculosis . Finally, modern global patterns of genetic diversity and ancient DNA studies indicate that during the last 5000 years plague caused by Yersinia pestis has spread globally on multiple occasions from China and Central Asia. Such tMRCA estimates provide only lower bounds on the ages of bacterial pathogens, and additional studies are needed for realistic upper bounds on how long humans and animals have suffered from bacterial diseases.

scholarly journals Population genomics of Mycobacterium tuberculosis in the Inuit

2015 ◽  
Vol 112 (44) ◽  
pp. 13609-13614 ◽  
Author(s):  
Robyn S. Lee ◽  
Nicolas Radomski ◽  
Jean-Francois Proulx ◽  
Ines Levade ◽  
B. Jesse Shapiro ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Mycobacterium Tuberculosis ◽  
Population Genomics ◽  
Purifying Selection ◽  
Synonymous Substitution ◽  
Nonsynonymous Snps ◽  
Recent Common Ancestor ◽  
Nucleotide Polymorphisms ◽  
Most Recent Common Ancestor ◽  
Bacterial Genetic

Nunavik, Québec suffers from epidemic tuberculosis (TB), with an incidence 50-fold higher than the Canadian average. Molecular studies in this region have documented limited bacterial genetic diversity among Mycobacterium tuberculosis isolates, consistent with a founder strain and/or ongoing spread. We have used whole-genome sequencing on 163 M. tuberculosis isolates from 11 geographically isolated villages to provide a high-resolution portrait of bacterial genetic diversity in this setting. All isolates were lineage 4 (Euro-American), with two sublineages present (major, n = 153; minor, n = 10). Among major sublineage isolates, there was a median of 46 pairwise single-nucleotide polymorphisms (SNPs), and the most recent common ancestor (MRCA) was in the early 20th century. Pairs of isolates within a village had significantly fewer SNPs than pairs from different villages (median: 6 vs. 47, P < 0.00005), indicating that most transmission occurs within villages. There was an excess of nonsynonymous SNPs after the diversification of M. tuberculosis within Nunavik: The ratio of nonsynonymous to synonymous substitution rates (dN/dS) was 0.534 before the MRCA but 0.777 subsequently (P = 0.010). Nonsynonymous SNPs were detected across all gene categories, arguing against positive selection and toward genetic drift with relaxation of purifying selection. Supporting the latter possibility, 28 genes were partially or completely deleted since the MRCA, including genes previously reported to be essential for M. tuberculosis growth. Our findings indicate that the epidemiologic success of M. tuberculosis in this region is more likely due to an environment conducive to TB transmission than a particularly well-adapted strain.

scholarly journals Evolutionary dynamics of human and avian metapneumoviruses

2008 ◽  
Vol 89 (12) ◽  
pp. 2933-2942 ◽  
Author(s):  
Miranda de Graaf ◽  
Albert D. M. E. Osterhaus ◽  
Ron A. M. Fouchier ◽  
Edward C. Holmes
Keyword(s):  
Genetic Diversity ◽  
Evolutionary Dynamics ◽  
Recent Common Ancestor ◽  
Human Populations ◽  
Population Bottlenecks ◽  
Genetic Lineages ◽  
The Past ◽  
Most Recent Common Ancestor ◽  
Large Sets ◽  
Respiratory Tract Illnesses

Human (HMPV) and avian (AMPV) metapneumoviruses are closely related viruses that cause respiratory tract illnesses in humans and birds, respectively. Although HMPV was first discovered in 2001, retrospective studies have shown that HMPV has been circulating in humans for at least 50 years. AMPV was first isolated in the 1970s, and can be classified into four subgroups, A–D. AMPV subgroup C is more closely related to HMPV than to any other AMPV subgroup, suggesting that HMPV has emerged from AMPV-C upon zoonosis. Presently, at least four genetic lineages of HMPV circulate in human populations – A1, A2, B1 and B2 – of which lineages A and B are antigenically distinct. We used a Bayesian Markov Chain Monte Carlo (MCMC) framework to determine the evolutionary and epidemiological dynamics of HMPV and AMPV-C. The rates of nucleotide substitution, relative genetic diversity and time to the most recent common ancestor (TMRCA) were estimated using large sets of sequences of the nucleoprotein, the fusion protein and attachment protein genes. The sampled genetic diversity of HMPV was found to have arisen within the past 119–133 years, with consistent results across all three genes, while the TMRCA for HMPV and AMPV-C was estimated to have existed around 200 years ago. The relative genetic diversity observed in the four HMPV lineages was low, most likely reflecting continual population bottlenecks, with only limited evidence for positive selection.

scholarly journals Extensive genetic diversity of bat-borne polyomaviruses reveals inter-family host-switching events

2019 ◽  
Author(s):  
Zhizhou Tan ◽  
Gabriel Gonzalez ◽  
Jinliang Sheng ◽  
Jianmin Wu ◽  
Fuqiang Zhang ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Large Population ◽  
Recent Common Ancestor ◽  
Host Switching ◽  
Evolutionary Divergence ◽  
Dna Viruses ◽  
Most Recent Common Ancestor ◽  
Evolutionary Scheme ◽  
Horseshoe Bat ◽  
Horseshoe Bats

AbstractPolyomaviruses (PyVs) are small, double-stranded DNA tumor viruses carried by diverse vertebrates. PyVs have previously been considered highly host restricted in mammalian hosts, with host-switching events thought rare or nonexistent. Prior investigations have revealed short-range host-switching events of PyVs in two different African bat species within the horseshoe bat genusRhinolophus. Herein, we have conducted a systematic investigation of PyVs in 1,083 archived bat samples collected from five provinces across China, and identified 192 PyVs from 186 bats from 15 host species within 6 families (Rhinolophidae, Vespertilionidae, Hipposideridae, Emballonuridae, Miniopteridae and Pteropodidae) representing 28 newly-described PyVs, indicative of extensive genetic diversity of bat PyVs. Surprisingly, two PyVs were identified in multiple bat species from different families, and another PyV clustered phylogenetically with PyVs carried by bats from a different host family, indicative of three inter-family PyV host-switching events. The time to most recent common ancestor (tMRCA) of the three events was estimated at 0.02-11.6 million years ago (MYA), which is inconsistent with the estimated tMRCA of their respective bat hosts (36.3-66.7 MYA), and is most parsimoniously explained by host-switching events. PyVs identified from geographically separated Chinese horseshoe bat species in the present study showed close genetic identities, and clustered with each other and with PyVs from African horseshoe bats, allowing assessment of the effects of positive selection in VP1 within the horseshoe bat family Rhinolophidae. Correlation analysis indicated that co-evolution with their hosts contributed much more to evolutionary divergence of PyV than geographic distance. In conclusion, our findings provide the first evidence of inter-family host-switching events of PyV in mammals and challenge the prevailing evolutionary paradigm for strict host restriction of mammalian PyVs.Author summarySince the discovery of murine polyomavirus in the 1950s, polyomaviruses (PyVs) have been considered both genetically stable and highly host-restricted in their mammalian hosts. In this study, we have identified multiple cases of host-switching events of PyVs by large scale surveillance in diverse bat species collected in China. These host-switching events occurred between bat families living in the same colony, indicating that a large population with frequent contacts between different bat species may represent an ecological niche facilitating PyV host-switching. The cases studied involved members of bats from several families, including horseshoe bats, which were previously found to harbor a number of highly virulent viruses to both humans and domestic animals. Our findings have provided evidence that even highly host-specific DNA viruses can transmit between bats of different species and indicate an increased propensity for spillover events involving horseshoe bats. We propose an evolutionary scheme for bat-borne PyVs in which intra-host divergence and host-switching has generated the diverse PyVs in present day bats. This scheme provides a useful model to study the evolution of PyVs in other hosts and, potentially, the modeling of bat zoonoses and the transmission of other DNA viruses in other mammals, including humans.

scholarly journals Beyond RuBisCO: Convergent molecular evolution of multiple chloroplast genes in C4 plants

2021 ◽  
Author(s):  
Claudio Casola ◽  
Jingjia Li
Keyword(s):  
Amino Acid ◽  
Convergent Evolution ◽  
Protein Sequences ◽  
Recent Common Ancestor ◽  
Grass Species ◽  
Comparative Genomic ◽  
Chloroplast Genes ◽  
Chloroplast Proteins ◽  
Most Recent Common Ancestor ◽  
Molecular Convergence

AbstractBackgroundThe recurrent evolution of the C4 photosynthetic pathway in angiosperms represents one of the most extraordinary examples of convergent evolution of a complex trait. Comparative genomic analyses have unveiled some of the molecular changes associated with the C4 pathway. For instance, several key enzymes involved in the transition from C3 to C4 photosynthesis have been found to share convergent amino acid replacements along C4 lineages. However, the extent of convergent replacements potentially associated with the emergence of C4 plants remains to be fully assessed. Here, we introduced a robust empirical approach to test molecular convergence along a phylogeny including multiple C3 and C4 taxa. By analyzing proteins encoded by chloroplast genes, we tested if convergent replacements occurred more frequently than expected in C4 lineages compared to C3 lineages. Furthermore, we sought to determine if convergent evolution occurred in multiple chloroplast proteins beside the well-known case of the large RuBisCO subunit encoded by the chloroplast gene rbcL.MethodsOur study was based on the comparative analysis of 43 C4 and 21 C3 grass species belonging to the PACMAD clade, a focal taxonomic group in many investigations of C4 evolution. We first used protein sequences of 67 orthologous chloroplast genes to build an accurate phylogeny of these species. Then, we inferred amino acid replacements along 13 C4 lineages and 9 C3 lineages using reconstructed protein sequences of their ancestral branches, corresponding to the most recent common ancestor of each lineage. Pairwise comparisons between ancestral branches allowed us to identify both convergent and divergent amino acid replacements between C4-C4, C3-C3 and C3-C4 lineages.ResultsThe reconstructed phylogenetic tree of 64 PACMAD grasses was characterized by strong supports in all nodes used for analyses of convergence. We identified 217 convergent replacements and 201 divergent replacements in 45/67 chloroplast proteins in both C4 and C3 ancestral branches. Pairs of C4-C4 ancestral branches showed higher levels of convergent replacements than C3-C3 and C3-C4 pairs. Furthermore, we found that more proteins shared unique convergent replacements in C4 lineages, with both RbcL and RpoC1 (the RNA polymerase beta’ subunit 1) showing a significantly higher convergent/divergent replacements ratio in C4 branches. Notably, significantly more C4-C4 pairs of ancestral branches showed higher numbers of convergent vs. divergent replacements than C3-C3 and C3-C4 pairs. Our results demonstrated that, in the PACMAD clade, C4 grasses experienced higher levels of molecular convergence than C3 species across multiple chloroplast genes. These findings have important implications for both our understanding of the evolution of photosynthesis and the goal of engineering improved crop varieties that integrates components of the C4 pathway.

scholarly journals Diversitas Genetika dan Identifikasi Jenis Kelamin Burung Pelikan (Pelecanus conspicillatus Temminck, 1824) di Penangkaran Taman Margasatwa Ragunan Jakarta

2021 ◽  
Vol 17 (2) ◽  
pp. 105-114
Author(s):  
Anik Budhi Dharmayanthi ◽  
Achmad Muchsinin ◽  
Afriana Pulungan ◽  
Moch Syamsul Arifin Zein
Keyword(s):  
Genetic Diversity ◽  
Nucleotide Diversity ◽  
Haplotype Diversity ◽  
Population Expansion ◽  
Bird Populations ◽  
Low Genetic Diversity ◽  
In Captivity ◽  
D Loop ◽  
Haplotype 1

Pelicans (Pelecanus conspicillatus) is one of the wild species that have a widely distribution. This bird has been successfully bred in Ragunan Zoo, Jakarta. The indicator of inbreeding in the captive population is shown by the decrease of nucleotide diversity and number of haplotypes. The result of genetic diversity analysis using D-loop fragment sequences showed low genetic diversity with nucleotide diversity (p) = 0.00064 ± 0.00010 and haplotype diversity (Hd) = 0.532 ± 0.061 in Pelecanus conspicillatus populations in the Ragunan Zoo. However, negative Fu's Fs value (-3,246) indicates population expansion. We found that there were seven haplotypes in bird populations in the captivity: haplotype 1, 2 and 3 consist of 43 individuals (65.15%), five individuals (7.57%), and 14 individuals (21.21%), respectively. For each haplotype 4, 5, 6 and 7 is only represented by one individual of Pelecanus conspicillatus (1.51%). The sex ratio of males to females is 1: 8.86 with four males identified as haplotype 1, and one male on haplotypes 3, 5 and 7, respectively. Genetic diversity data of the population is an important way for designing long-term plans and goals in efforts to maintain genetic diversity of the Pelecanus conspicillatus population in captivity.

scholarly journals Evolution and Genetic Diversity of SARSCoV-2 in Africa Using Whole Genome Sequences

2020 ◽  
Author(s):  
Babatunde Olarenwaju Motayo ◽  
Olukunle Oluwapamilerin Oluwasemowo ◽  
Paul Akiniyi Akinduti ◽  
Babatunde Adebiyi Olusola ◽  
Olumide T Aerege ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Amino Acid ◽  
Spike Protein ◽  
Recent Common Ancestor ◽  
Whole Genome ◽  
Genome Sequences ◽  
Protein Amino Acid ◽  
Protein Variant ◽  
Health Crisis ◽  
Most Recent Common Ancestor

ABSTRACTThe ongoing SARSCoV-2 pandemic was introduced into Africa on 14th February 2020 and has rapidly spread across the continent causing severe public health crisis and mortality. We investigated the genetic diversity and evolution of this virus during the early outbreak months using whole genome sequences. We performed; recombination analysis against closely related CoV, Bayesian time scaled phylogeny and investigated spike protein amino acid mutations. Results from our analysis showed recombination signals between the AfrSARSCoV-2 sequences and reference sequences within the N and S genes. The evolutionary rate of the AfrSARSCoV-2 was 4.133 × 10−4 high posterior density HPD (4.132 × 10−4 to 4.134 × 10−4) substitutions/site/year. The time to most recent common ancestor TMRCA of the African strains was December 7th 2019. The AfrSARCoV-2 sequences diversified into two lineages A and B with B being more diverse with multiple sub-lineages confirmed by both maximum clade credibility MCC tree and PANGOLIN software. There was a high prevalence of the D614-G spike protein amino acid mutation (82.61%) among the African strains. Our study has revealed a rapidly diversifying viral population with the G614 spike protein variant dominating, we advocate for up scaling NGS sequencing platforms across Africa to enhance surveillance and aid control effort of SARSCoV-2 in Africa.

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