scholarly journals Phylogeography and Evolutionary analysis of African Rotavirus A genotype G12 reveals district genetic diversification within Lineage III

2019 ◽  
Author(s):  
Babatunde Olanrewaju Motayo ◽  
Olukunle Oluwasemowo ◽  
Babatunde Adebiyi Olusola ◽  
Adewale Victor Opayele ◽  
Adedayo Omotayo Faneye

AbstractRotavirus genotype G12 has become one of the most prevalent genotypes of rotavirus in Africa. To understand the drivers for its genetic diversity we investigated the Bayesian phylogeney, evolution and population demography of the genotype G12 Africa. Rotavirus genotype G12, VP7 sequences were downloaded and aligned from twelve African countries (n=96). Phylogenetic analysis, Evolutionary analysis and Bayesian Phylogeography was carried out, using MEGA Vs 6, BEAST, and SPREAD3. Phylogeny showed that all the African sequences fell into lineage III diversifying into two major clades. The evolutionary rate was 1.678×10-3 (95%HPD, 1.201×10-3 -2.198×10-3) substitutions/ site/ year. The MCC tree topology clustered into three lineages (II, III, IV), African strains diversified into three clusters within lineage III. South Africa was the epicentre of viral dispersal. This study shows the potential for genetic diversification of Rotavirus G12 in Africa, continuous molecular surveillance across Africa is recommended to help control effort.HighlightsOur study revealed that African G12 rotaviruses have diversified into 3 clades within their parental lineage III based on geographic boundaries.Nigeria was identified Nigeria as country of origin, while South Africa served as the epicentre of dispersal of the genotype across Africa.We also discovered that they have a constant demographic profile. Our findings reveal the potential for rapid genetic diversity of Rotavirus G12 and highlight the importance of molecular surveillance in Rotavirus control effort.

2013 ◽  
Vol 94 (4) ◽  
pp. 738-748 ◽  
Author(s):  
Ying Tao ◽  
Mang Shi ◽  
Christina Conrardy ◽  
Ivan V. Kuzmin ◽  
Sergio Recuenco ◽  
...  

Polyomaviruses (PyVs) have been identified in a wide range of avian and mammalian species. However, little is known about their occurrence, genetic diversity and evolutionary history in bats, even though bats are important reservoirs for many emerging viral pathogens. This study screened 380 specimens from 35 bat species from Kenya and Guatemala for the presence of PyVs by semi-nested pan-PyV PCR assays. PyV DNA was detected in 24 of the 380 bat specimens. Phylogenetic analysis revealed that the bat PyV sequences formed 12 distinct lineages. Full-genome sequences were obtained for seven representative lineages and possessed similar genomic features to known PyVs. Strikingly, this evolutionary analysis revealed that the bat PyVs were paraphyletic, suggestive of multiple species jumps between bats and other mammalian species, such that the theory of virus–host co-divergence for mammalian PyVs as a whole could be rejected. In addition, evidence was found for strong heterogeneity in evolutionary rate and potential recombination in a number of PyV complete genomes, which complicates both phylogenetic analysis and virus classification. In summary, this study revealed that bats are important reservoirs of PyVs and that these viruses have a complex evolutionary history.


Author(s):  
R. Kann ◽  
J. Seddon ◽  
M. Kyaw-Tanner ◽  
J.P. Schoeman ◽  
T. Schoeman ◽  
...  

Feline immunodeficiency virus (FIV), a lentivirus, is an important pathogen of domestic cats around the world and has many similarities to human immunodeficiency virus (HIV). A characteristic of these lentiviruses is their extensive genetic diversity, which has been an obstacle in the development of successful vaccines. Of the FIV genes, the envelope gene is the most variable and sequence differences in a portion of this gene have been used to define 5 FIV subtypes (A, B, C, D and E). In this study, the proviral DNA sequence of the V3-V5 region of the envelope gene was determined in blood samples from 31 FIV positive cats from 4 different regions of South Africa. Phylogenetic analysis demonstrated the presence of both subtypes A and C, with subtype A predominating. These findings contribute to the understanding of the genetic diversity of FIV.


2021 ◽  
Author(s):  
Kebareng G. Rakau ◽  
Martin M. Nyaga ◽  
Maemu P. Gededzha ◽  
Jason M. Mwenda ◽  
M. Jeffrey Mphahlele ◽  
...  

Abstract Background: G12 rotaviruses were first observed in sub-Saharan Africa in 2004 and since then have continued to emerge and spread across the continent and are reported as a significant human rotavirus genotype in several African countries, both prior to and after rotavirus vaccine introduction. This study investigated the genetic variability of 15 G12 rotavirus strains associated with either P[6] or P[8] identified between 2010 and 2014 from Ethiopia, Kenya, Rwanda, Tanzania, Togo and Zambia.Methods: The investigation was carried out by comparing partial VP7 and partial VP4 sequences of the African G12P[6] and G12P[8] strains with the available GenBank sequences and exploring the recognized neutralization epitopes of these strains. Additionally, Bayesian evolutionary analysis was carried out using Markov Chain Monte Carlo (MCMC) implemented in BEAST to estimate the time to the most recent ancestor and evolutionary rate for these G12 rotavirus strains.Results: The findings suggested that the VP7 and VP4 nucleotide and amino acid sequences of the G12 strains circulating in African countries are closely related, irrespective of country of origin and year of detection, with the exception of the Ethiopian strains that clustered distinctly. Neutralization epitope analysis revealed that rotavirus VP4 P[8] genes associated with G12 had amino acid sequences similar to those reported globally including the vaccine strains in RotaTeq and Rotarix. The estimated evolutionary rate of the G12 strains was 1.016 x10−3 substitutions/site/year and was comparable to what has been previously reported. Three sub-clusters formed within the current circulating lineage III shows the diversification of G12 from three independent ancestries within a similar time frame in the late 1990s.Conclusions: At present it appears to be unlikely that widespread vaccine use has driven the molecular evolution and sustainability of G12 strains in Africa. Continuous monitoring of rotavirus genotypes is recommended to assess the long-term impact of rotavirus vaccination on the dynamic nature of rotavirus evolution on the continent.


Pathogens ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1026
Author(s):  
Benilde Munlela ◽  
Eva D. João ◽  
Celeste M. Donato ◽  
Amy Strydom ◽  
Simone S. Boene ◽  
...  

Mozambique introduced the Rotarix® vaccine (GSK Biologicals, Rixensart, Belgium) into the National Immunization Program in September 2015. Although G1P[8] was one of the most prevalent genotypes between 2012 and 2017 in Mozambique, no complete genomes had been sequenced to date. Here we report whole genome sequence analysis for 36 G1P[8] strains using an Illumina MiSeq platform. All strains exhibited a Wa-like genetic backbone (G1-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1). Phylogenetic analysis showed that most of the Mozambican strains clustered closely together in a conserved clade for the entire genome. No distinct clustering for pre- and post-vaccine strains were observed. These findings may suggest no selective pressure by the introduction of the Rotarix® vaccine in 2015. Two strains (HJM1646 and HGM0544) showed varied clustering for the entire genome, suggesting reassortment, whereas a further strain obtained from a rural area (MAN0033) clustered separately for all gene segments. Bayesian analysis for the VP7 and VP4 encoding gene segments supported the phylogenetic analysis and indicated a possible introduction from India around 2011.7 and 2013.0 for the main Mozambican clade. Continued monitoring of rotavirus strains in the post-vaccine period is required to fully understand the impact of vaccine introduction on the diversity and evolution of rotavirus strains.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Kebareng G. Rakau ◽  
Martin M. Nyaga ◽  
Maemu P. Gededzha ◽  
Jason M. Mwenda ◽  
M. Jeffrey Mphahlele ◽  
...  

Abstract Background G12 rotaviruses were first observed in sub-Saharan Africa in 2004 and since then have continued to emerge and spread across the continent and are reported as a significant human rotavirus genotype in several African countries, both prior to and after rotavirus vaccine introduction. This study investigated the genetic variability of 15 G12 rotavirus strains associated with either P[6] or P[8] identified between 2010 and 2014 from Ethiopia, Kenya, Rwanda, Tanzania, Togo and Zambia. Methods The investigation was carried out by comparing partial VP7 and partial VP4 sequences of the African G12P[6] and G12P[8] strains with the available GenBank sequences and exploring the recognized neutralization epitopes of these strains. Additionally, Bayesian evolutionary analysis was carried out using Markov Chain Monte Carlo (MCMC) implemented in BEAST to estimate the time to the most recent ancestor and evolutionary rate for these G12 rotavirus strains. Results The findings suggested that the VP7 and VP4 nucleotide and amino acid sequences of the G12 strains circulating in African countries are closely related, irrespective of country of origin and year of detection, with the exception of the Ethiopian strains that clustered distinctly. Neutralization epitope analysis revealed that rotavirus VP4 P[8] genes associated with G12 had amino acid sequences similar to those reported globally including the vaccine strains in RotaTeq and Rotarix. The estimated evolutionary rate of the G12 strains was 1.016 × 10− 3 substitutions/site/year and was comparable to what has been previously reported. Three sub-clusters formed within the current circulating lineage III shows the diversification of G12 from three independent ancestries within a similar time frame in the late 1990s. Conclusions At present it appears to be unlikely that widespread vaccine use has driven the molecular evolution and sustainability of G12 strains in Africa. Continuous monitoring of rotavirus genotypes is recommended to assess the long-term impact of rotavirus vaccination on the dynamic nature of rotavirus evolution on the continent.


2020 ◽  
Author(s):  
Kebareng G. Rakau ◽  
Martin M. Nyaga ◽  
Maemu P. Gededzha ◽  
Jason M. Mwenda ◽  
M. Jeffrey Mphahlele ◽  
...  

Abstract Background: G12 rotaviruses were first observed in sub-Saharan Africa in 2004 and since then have continued to emerge and spread across the continent and are reported as a significant human rotavirus genotype in several African countries, both prior to and after rotavirus vaccine introduction. This study investigated the genetic variability of 15 G12 rotavirus strains associated with either P[6] or P[8] identified between 2010 and 2014 from Ethiopia, Kenya, Rwanda, Tanzania, Togo and Zambia. Methods: The investigation was carried out by comparing partial VP7 and partial VP4 sequences of the African G12P[6] and G12P[8] strains with the available GenBank sequences and exploring the recognized neutralization epitopes of these strains. Additionally, Bayesian evolutionary analysis was carried out using Markov Chain Monte Carlo (MCMC) implemented in BEAST to estimate the time to the most recent ancestor and evolutionary rate for these G12 rotavirus strains.Results: The findings suggested that the VP7 and VP4 nucleotide and amino acid sequences of the G12 strains circulating in African countries are closely related , irrespective of country of origin and year of detection, with the exception of the Ethiopian strains that clustered distinctly. Neutralization epitope analysis revealed that rotavirus VP4 P[8] genes associated with G12 had amino acid sequences similar to those reported globally including the vaccine strains in RotaTeq and Rotarix. The estimated evolutionary rate of the G12 strains was 1.016 x10−3 substitutions/site/year and was comparable to what has been previously reported. Three sub-clusters formed within the current circulating lineage III shows the diversification of G12 from three independent ancestries within a similar time frame in the late 1990s.Conclusions: At present it appears to be unlikely that widespread vaccine use has driven the molecular evolution and sustainability of G12 strains in Africa. Continuous monitoring of rotavirus genotypes is recommended to assess the long-term impact of rotavirus vaccination on the dynamic nature of rotavirus evolution on the continent.


Plants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 15
Author(s):  
Badreddine Sijilmassi ◽  
Abdelkarim Filali-Maltouf ◽  
Hassan Boulahyaoui ◽  
Aymane Kricha ◽  
Kenza Boubekri ◽  
...  

A total of 14 Rhizobium strains were isolated from lentil accessions grown at the ICARDA experimental research station at Marchouch in Morocco and used for molecular characterization and symbiotic efficiency assessment. Individual phylogenetic analysis using the 16S rRNA gene, house-keeping genes rpoB, recA, and gyrB, and symbiotic genes nodD and nodA along with Multilocus Sequence Analysis (MLSA) of the concatenated genes (16S rRNA-rpoB-recA-gyrB) was carried out for the identification and clustering of the isolates. The symbiotic efficiency of the strains was assessed on three Moroccan lentil cultivars (Bakria, Chakkouf, and Zaria) based on the number of nodules, plant height, plant dry weight, and total nitrogen content in leaves. The results showed that the individual phylogenetic analysis clustered all the strains into Rhizobium laguerreae and Rhizobium leguminosarum with sequence similarity ranging from 94 to 100%, except one strain which clustered with Mesorhizobium huakuii with sequence similarity of 100%. The MLSA of the concatenated genes and the related percentages of similarity clustered these strains into two groups of Rhizobium species, with one strain as a new genospecies when applying the threshold of 96%. For symbiotic efficiency, the Bakria variety showed the best association with 10 strains compared to its non-inoculated control (p-value ≤ 0.05), followed by Chakkouf and Zaria. The present study concluded that the genetic diversity and the symbiotic efficiency of Rhizobium strains appeared to be mainly under the control of the lentil genotypes.


Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 89
Author(s):  
Jiayu Li ◽  
Fuxian Yang ◽  
Ruobing Liang ◽  
Sheng Guo ◽  
Yaqiong Guo ◽  
...  

Cryptosporidiumfelis is an important cause of feline and human cryptosporidiosis. However, the transmission of this pathogen between humans and cats remains controversial, partially due to a lack of genetic characterization of isolates from cats. The present study was conducted to examine the genetic diversity of C. felis in cats in China and to assess their potential zoonotic transmission. A newly developed subtyping tool based on a sequence analysis of the 60-kDa glycoprotein (gp60) gene was employed to identify the subtypes of 30 cat-derived C. felis isolates from Guangdong and Shanghai. Altogether, 20 C. felis isolates were successfully subtyped. The results of the sequence alignment showed a high genetic diversity, with 13 novel subtypes and 2 known subtypes of the XIXa subtype family being identified. The known subtypes were previously detected in humans, while some of the subtypes formed well-supported subclusters with human-derived subtypes from other countries in a phylogenetic analysis of the gp60 sequences. The results of this study confirmed the high genetic diversity of the XIXa subtype family of C. felis. The common occurrence of this subtype family in both humans and cats suggests that there could be cross-species transmission of C. felis.


Author(s):  
Samuel Kwasi Opoku ◽  
Walter Leal Filho ◽  
Fudjumdjum Hubert ◽  
Oluwabunmi Adejumo

Climate change is a global problem, which affects the various geographical regions at different levels. It is also associated with a wide range of human health problems, which pose a burden to health systems, especially in regions such as Africa. Indeed, across the African continent public health systems are under severe pressure, partly due to their fragile socioeconomic conditions. This paper reports on a cross-sectional study in six African countries (Ghana, Nigeria, South Africa, Namibia, Ethiopia, and Kenya) aimed at assessing their vulnerabilities to climate change, focusing on its impacts on human health. The study evaluated the levels of information, knowledge, and perceptions of public health professionals. It also examined the health systems’ preparedness to cope with these health hazards, the available resources, and those needed to build resilience to the country’s vulnerable population, as perceived by health professionals. The results revealed that 63.1% of the total respondents reported that climate change had been extensively experienced in the past years, while 32% claimed that the sampled countries had experienced them to some extent. Nigerian respondents recorded the highest levels (67.7%), followed by Kenya with 66.6%. South Africa had the lowest level of impact as perceived by the respondents (50.0%) when compared with the other sampled countries. All respondents from Ghana and Namibia reported that health problems caused by climate change are common in the two countries. As perceived by the health professionals, the inadequate resources reiterate the need for infrastructural resources, medical equipment, emergency response resources, and technical support. The study’s recommendations include the need to improve current policies at all levels (i.e., national, regional, and local) on climate change and public health and to strengthen health professionals’ skills. Improving the basic knowledge of health institutions to better respond to a changing climate is also recommended. The study provides valuable insights which may be helpful to other nations in Sub-Saharan Africa.


2014 ◽  
Vol 43 (1) ◽  
pp. 87-96 ◽  
Author(s):  
Charfeddine Gharsallah ◽  
Amina Ben Halima ◽  
Hatem Fakhfakh ◽  
Faten Gorsane

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