scholarly journals ­Rotavirus group A genotype circulation patterns across Kenya before and after nationwide vaccine introduction, 2010-2018

2020 ◽  
Author(s):  
Mike Mwanga ◽  
Betty Owor ◽  
John Ocheing ◽  
Mwanajuma Ngama ◽  
Billy Ogwel ◽  
...  
Keyword(s):  
Enzyme Linked Immunosorbent Assay ◽  
Genotype Distribution ◽  
Vaccine Introduction ◽  
Circulation Patterns ◽  
Before And After ◽  
Epidemiological Changes ◽  
Group A ◽  
Vaccine Impact ◽  
Stool Samples

Abstract Background: Kenya introduced the monovalent G1P[8] Rotarix® vaccine into the infant immunization schedule in July 2014. We examined trends in rotavirus group A (RVA) genotype distribution pre- (January 2010 - June 2014) and post- (July 2014-December 2018) RVA vaccine introduction.Methods: Stool samples were collected from children aged <13 years from four surveillance sites across Kenya: Kilifi County Hospital, Tabitha Clinic, Lwak Mission Hospital, and Siaya County Referral Hospital (children aged <5 years only). Samples were screened for RVA using enzyme linked immunosorbent assay (ELISA) and G and P genes sequenced to infer genotypes.Results: We genotyped 614 samples in pre-vaccine and 261 in post-vaccine introduction periods. During the pre-vaccine introduction period, the most frequent RVA genotypes were G1P[8] (45.8%), G8P[4] (15.8%), G9P[8] (13.2%), G2P[4] (7.0%) and G3P[6] (3.1%). In the post-vaccine introduction period, the most frequent genotypes were G1P[8] (52.1%), G2P[4] (20.7%) and G3P[8] (16.1%). Predominant genotypes varied by year and site in both pre and post-vaccine periods. Temporal genotype patterns showed an increase in prevalence of heterotypic commonly DS-1-like G2P[4] (7.0 to 20.7%, P <.001) and G3P[8] (1.3 to 16.1%, P< .001) genotypes in the post-vaccine introduction period. Additionally, we observed a decline in prevalence of genotypes G8P[4] (15.8 to 0.4%, P <.001) and G9P[8] (13.2 to 5.4%, P <.001) in the post-vaccine introduction period.Conclusion: Genotype prevalence varied from before to after vaccine introduction. Such observations emphasize the need for long-term surveillance to monitor vaccine impact. These changes may represent natural secular variation or possible immuno-epidemiological changes arising from the introduction of the vaccine. Full length sequencing could provide insights into post-vaccine evolutionary pressures and antigenic diversity.

scholarly journals Rotavirus group A genotype circulation patterns across Kenya before and after nationwide vaccine introduction, 2010–2018

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Mike J. Mwanga ◽  
Betty E. Owor ◽  
John B. Ochieng ◽  
Mwanajuma H. Ngama ◽  
Billy Ogwel ◽  
...  
Keyword(s):  
Vaccine Introduction ◽  
Circulation Patterns ◽  
Before And After ◽  
Group A

Molecular Detection of Group A Rotavirus in under Five Years Old Children with Acute Diarrhoea Admitted to Yangon Children’s Hospital

2019 ◽  
Vol 31 (1) ◽  
pp. 87-92
Keyword(s):  
Acute Diarrhoea ◽  
Enzyme Linked Immunosorbent Assay ◽  
Viral Gastroenteritis ◽  
Cross Sectional ◽  
Under Five ◽  
Group A Rotavirus ◽  
Rotavirus Vaccination ◽  
Group A ◽  
Stool Samples ◽  
Considerable Morbidity

Rotaviruses are regarded as the most common cause of viral gastroenteritis and are responsible for considerable morbidity and mortality among children especially under five years of age worldwide. In developing countries like Myanmar, where diarrhoea is in the priority childhood disease, rotavirus surveillance and detection of rotavirus genotypes are utmost important. A hospital-based, cross-sectional descriptive study was conducted at Yangon Children‟s Hospital among under five children admitted for acute diarrhoea from January to October 2016. This study includes detection of Group A rotavirus antigen by commercial enzyme-linked immunosorbent assay (ELISA) and genotyping by multiplex RT-PCR. From a total of 488 collected samples, rotavirus antigen was detected in 219 samples (45%). Rotavirus diarrhoea was most common among the age of 6-11 months (38.8%) followed by 12-23 months (37.9%). The results showed that boys were more commonly affected than girls. Detection of rotavirus positivity was peak in February (57.6 %). Out of 219 stool samples with positive ELISA result, 40 stool samples with high optical density value were proceeded for further determination of G and P genotypes. Regarding distribution of G genotypes, the most common G genotype was G9 which comprised 45%, and that of P genotype was P[8] which comprised 92.5%. Regarding combination of G and P genotypes, the most frequent combination is G9P[8], and it constituted 42.5%. Untypable genotypes were seen in 30% of G and 2.5% of P typing. As rotavirus infection can be prevented by vaccine, WHO recommended that rotavirus vaccination should be included in national immunization program especially in countries where prevalence of rotavirus is high. The distribution of G and P genotypes is important in consideration of appropriate vaccine in pre-vaccination and evaluation of effectiveness of vaccine in post-vaccination period. Therefore, the information on currently circulating genotypes of rotavirus in this study will serve as valuable data for vaccination programme.

scholarly journals PREPARATION AND EVALUATION OF CHEMICALLY INACTIVATED SALMONELLA ENTERITIDIS VACCINE IN CHICKENS

2017 ◽  
Vol 10 (11) ◽  
pp. 341
Author(s):  
Mounir M El-safty ◽  
Hala Mahmoud ◽  
Eman Sa Zaki ◽  
Howaida I Abd-alla
Keyword(s):  
Immune Responses ◽  
Salmonella Enteritidis ◽  
Serum Antibody ◽  
Enzyme Linked Immunosorbent Assay ◽  
Control Group ◽  
Chemically Induced ◽  
Before And After ◽  
Group A ◽  
Group B ◽  
Cell Envelopes

  Objective: Salmonella enteritidis ghosts (SEGs) is a non-living empty bacterial cell envelopes which were generated using a different concentration of sodium hydroxide (NaOH) 6.4 mg/mL and evaluated as a vaccine candidate in specific pathogen-free (SPF) chicken. SEGs have been produced by chemical-mediated lysis and evaluated the potential efficacy of chemically induced SEG vaccine and its ability to induce protective immune responses against virulent S. enteritidis challenge in SPF chickens.Methods: SPF chickens were divided into three groups: Group A (non-vaccinated control), Group B (vaccinated with prepared vaccine), and Group C (vaccinated with commercial vaccine).Results: Vaccination of SPF chicken with SEGs induced higher immune responses before and after virulent challenge. SPF chicken vaccinated with SEGs showed increasing in serum enzyme-linked immunosorbent assay (ELISA) antibodies. During the vaccination period, Groups B and C showed higher serum antibody titer compared to Group A. The minimal inhibitory concentration (MIC) of NaOH was capable of inducing non-living SEGs, and it has successfully generated non-living SEGs by MIC of NaOH.Conclusion: It is a one-step process which means easy manufacturing and low production cost compared to protein E-mediated lysis method. Chemically induced SEG vaccine is a highly effective method for inducing protective immunity. This study strongly suggests that SEGs will be a permissive vaccine, as the method of inhibition of S. enteritidis was safe and cheaper than other methods, and it gave a good protection.

scholarly journals Multiple Introductions and Predominance of Rotavirus Group A Genotype G3P[8] in Coastal Kenya in 2018, 4 Years After Nationwide Vaccine Introduction

2020 ◽  
Author(s):  
Mike J. Mwanga ◽  
Jennifer R. Verani ◽  
Richard Omore ◽  
Jacqueline E. Tate ◽  
Umesh D. Parashar ◽  
...  
Keyword(s):  
Vaccine Coverage ◽  
Childhood Diarrhea ◽  
Vaccine Failure ◽  
Multiple Introductions ◽  
Vaccine Introduction ◽  
Coastal Kenya ◽  
Group A ◽  
Genetic Clusters ◽  
Global Nature ◽  
Stool Samples

Globally, rotavirus group A (RVA) remains a major cause of severe childhood diarrhea, despite the use of vaccines in &amp;gt; 100 countries. RVA sequencing for local outbreaks facilitates investigation into strain composition, origins, spread, and vaccine failure. In 2018, we collected 248 stool samples from children aged &amp;lt;13 years admitted with diarrheal illness to Kilifi County Hospital, coastal Kenya. Antigen screening detected RVA in 55 samples (22.2%). Of these, VP7 (G) and VP4 (P) segments were successfully sequenced in 48 (87.3%) and phylogenetic analysis based on the VP7 sequences identified seven genetic clusters with six different GP combinations; G3P[8], G1P[8], G2P[4], G2P[8], G9P[8] and G12P[8]. The G3P[8] strains predominated the season (n=37, 67.2%) and comprised three G3 genetic clusters that fell within Lineage I and IX (the latter also known as equine-like G3 lineage). Both two G3 lineages have been recently detected in several countries. Our study is the first to document African children infection with G3 lineage IX. These data highlight the global nature of RVA transmission and the importance of increasing global rotavirus vaccine coverage.

scholarly journals Distinct yearly change of serotype distribution of human rotavirus in Thailand as determined by ELISA and PCR

1993 ◽  
Vol 111 (2) ◽  
pp. 407-412 ◽  
Author(s):  
Y. Pongsuwanna ◽  
K. Taniguchi ◽  
F. Wakasugi ◽  
Y. Sutivijit ◽  
M. Chiwakul ◽  
...  
Keyword(s):  
Enzyme Linked Immunosorbent Assay ◽  
Serotype Distribution ◽  
Chain Reaction ◽  
Positive Stool ◽  
Human Rotavirus ◽  
Serotype 1 ◽  
Group A ◽  
Yearly Change ◽  
Stool Samples ◽  
Polymerase Chain

SummaryA total of 241 group A rotavirus-positive stool samples collected from diarrhoeic patients in Thailand between July 1988 and June 1991 were characterized for their serotypes by enzyme-linked immunosorbent assay (ELISA) using serotype-specific monoclonal antibodies and by a polymerase chain reaction (PCR). In July 1988–June 1989, serotype 1 was the most prevalent (63·4%), followed by serotype 4 (11·0%) and serotype 2 (8·5%). In July 1989–June 1990, 59·8% were serotype 1, 24·3% were serotype 2, and 6·1 % were serotype 3. In contrast, in July 1990–June 1991, serotype 3 was detected in the highest frequency (40·5%), 29·9% were serotype 1, and 27·3% were serotype 2. Thus, a distinct yearly change of serotype distribution of rotavirus in Thailand was observed in the three consecutive years. In particular, it was of note that the prevalence of serotype 3 greatly increased, in contrast to the previous studies in which almost no serotype 3 rotaviruses were detected in the years 1983–8 in Thailand.

Molecular characterization of rotaviruses in mid-western Turkey, 2006–2007

Open Medicine ◽  
2010 ◽  
Vol 5 (5) ◽  
pp. 640-645
Author(s):  
Mustafa Altindis ◽  
Krisztián Bányai ◽  
Raike Kalayci ◽  
Cihangir Gulamber ◽  
Resit Koken ◽  
...  
Keyword(s):  
Immune Escape ◽  
Local Strain ◽  
Western Turkey ◽  
Vaccine Introduction ◽  
Rotavirus Vaccines ◽  
Group A ◽  
Stool Samples ◽  
Commercial Enzyme Immunoassay ◽  
P Type

AbstractVaccines against rotaviruses are now available in numerous countries, including Turkey. As the vaccines may show various efficiencies against different type specificities and routine vaccination in infants might result in selection and immune escape of wild-type rotavirus strains, strain surveillance has been initiated before and during the vaccine introduction. We aimed to provide corresponding information on local strain prevalence in Anatolia, mid-western Turkey during the introduction of rotavirus vaccines. Stool samples positive for group A rotavirus by commercial enzyme immunoassay were subjected to reverse transcription-polymerase chain reaction based genotyping of the outer capsid antigens, VP7 and VP4, determining G and P type specificities respectively. Among 36 fully and 5 partially typeable strains we detected genotype G1, G2, and G9 VP7 specificities and genotype P[4], P[6] and P[8] VP4 specificities in 5 individual and 4 mixed combinations. The most common strain was G2P[4] (n=17), followed by G9P[8] (n=9). Other strains were G1P[8] (n=2), G2P[8] (n=2), G1+2P[8] (n=2), G9P[4] (n=1), G2+9P[8] (n=1), G4+9P[6] (n=1), and G2P[4+8] (n=1). Partially typed strains included 2 G1P[NT] and 3 G2P[NT] strains. Our data may help determine a baseline of the rotavirus genotype prevalence in Turkey and see if changes in the incidence of individual strains will be observed after routine use of vaccine.

scholarly journals Combination of Aerobics and Resistance Training to Obesity University Student Serum Visfatin Level Influence

2015 ◽  
Vol 9 (1) ◽  
pp. 424-428
Author(s):  
Xuhui Li ◽  
Xiaomei Fan
Keyword(s):  
Resistance Training ◽  
University Students ◽  
Blood Lipid ◽  
University Student ◽  
Control Group ◽  
Fat Percentage ◽  
Before And After ◽  
Group A ◽  
Visfatin Level

Purpose: Discuss on combination of long-term aerobics and resistance training to obesity university student serum visfatin level and blood lipid metabolism influence, and reveal potential mechanism of losing weight through exercises. Method: Divide 30 obesity university students into 3 groups, control group (group C), aerobics group (group A as well as aerobics and resistance training combinative group (group A+R), take in 16 periods’ training, before and after intervention respectively test the three groups’ weight (W), body mass index (BMI),fat mass (FM), fat percentage (%F); serum TG,TCH,HDL-C,LDL-C content and visfatin level, result:16 after 16 weeks sports intervention, compare group A and group A+R with group C, W,BMI,FM,%F obvious drop (P<0.05); serum TG,TCH,LDL-C content obvious drop (P<0.05), serum HDL-C obvious rises (P<0.05), serum visfatin content obvious drops (P<0.05), compare group A+R with group A, the FM,%F and serum visfatin content obvious drop, other indicators have no significant differences. Relevant analysis finds that serum visfatin content is positive correlated to W, BMI, FM, F%, TG, TCH and LDL-C(P<0.05), and is negative correlated to HDL-C. Conclusion: Both 16 weeks’ aerobics as well as combination of aerobics and resistance training have good improvements to obesity university students’ weight and body composition, and have good adjustment on blood lipid metabolic disorder, and reduce serum visfatin level. Combination of aerobics and resistance training has more obvious impacts on FM, % F and serum visfatin content, and meanwhile, serum visfatin level is positive correlated to weight, BMI, %F, FM, TG, TCH, LDL-C, while is negative correlated to HDL-C.

scholarly journals Molecular characterization of rotavirus group A strains circulating prior to vaccine introduction in rural coastal Kenya, 2002-2013

2019 ◽  
Vol 3 ◽  
pp. 150
Author(s):  
Betty E. Owor ◽  
Mike J. Mwanga ◽  
Regina Njeru ◽  
Robert Mugo ◽  
Mwanajuma Ngama ◽  
...  
Keyword(s):  
Temporal Fluctuations ◽  
Consensus Sequences ◽  
Vaccine Introduction ◽  
Coastal Kenya ◽  
Circulation Patterns ◽  
Sequencing Method ◽  
Group A ◽  
Wide Scale ◽  
Classification Tool ◽  
The Impact

Background: Kenya introduced the monovalent Rotarix® rotavirus group A (RVA) vaccine nationally in mid-2014.  Long-term surveillance data is important prior to wide-scale vaccine use to assess the impact on disease and to investigate the occurrence of heterotypic strains arising through immune selection. This report presents baseline data on RVA genotype circulation patterns and intra-genotype genetic diversity over a 7-year period in the pre-vaccine era in Kilifi, Kenya, from 2002 to 2004 and from 2010 to 2013. Methods: A total of 745 RVA strains identified in children admitted with acute gastroenteritis to a referral hospital in Coastal Kenya, were sequenced using the di-deoxy sequencing method in the VP4 and VP7 genomic segments (encoding P and G proteins, respectively). Sequencing successfully generated 569 (76%) and 572 (77%) consensus sequences for the VP4 and VP7 genes respectively. G and P genotypes were determined by use of BLAST and the online RotaC v2 RVA classification tool. Results: The most common GP combination was G1P[8] (51%), similar to the Rotarix® strain, followed by G9P[8] (15%) , G8P[4] (14%) and G2P[4] (5%).  Unusual GP combinations—G1P[4], G2P[8], G3P[4,6], G8P[8,14], and G12P[4,6,8]—were observed at frequencies of <5%. Phylogenetic analysis showed that the infections were caused by both locally persistent strains as evidenced by divergence of local strains occurring over multiple seasons from the global ones, and newly introduced strains, which were closely related to global strains. The circulating RVA diversity showed temporal fluctuations both season by season and over the longer-term. None of the unusual strains increased in frequency over the observation period.   Conclusions: The circulating RVA diversity showed temporal fluctuations with several unusual strains recorded, which rarely caused major outbreaks.  These data will be useful in interpreting genotype patterns observed in the region during the vaccine era.

scholarly journals Group A rotavirus surveillance before vaccine introduction in Italy, September 2014 to August 2017

2019 ◽  
Vol 24 (15) ◽  
Author(s):  
Giovanni Ianiro ◽  
Roberto Micolano ◽  
Ilaria Di Bartolo ◽  
Gaia Scavia ◽  
Marina Monini ◽  
...  
Keyword(s):  
Low Income ◽  
Acute Gastroenteritis ◽  
Paediatric Population ◽  
Low Income Countries ◽  
Mixed Infections ◽  
Genotype Distribution ◽  
Vaccine Introduction ◽  
Glycoprotein G ◽  
Group A Rotaviruses ◽  
Group A

Introduction Group A rotaviruses (RVA) are the leading cause of acute gastroenteritis (AGE) in young children, causing ca 250,000 deaths worldwide, mainly in low-income countries. Two proteins, VP7 (glycoprotein, G genotype) and VP4 (protease-sensitive protein, P genotype), are the basis for the binary RVA nomenclature. Although 36 G types and 51 P types are presently known, most RVA infections in humans worldwide are related to five G/P combinations: G1P[8], G2P[4], G3P[8], G4P[8], G9P[8]. Aim This study aimed to characterise the RVA strains circulating in Italy in the pre-vaccination era, to define the trends of circulation of genotypes in the Italian paediatric population. Methods Between September 2014 and August 2017, after routine screening in hospital by commercial antigen detection kit, 2,202 rotavirus-positive samples were collected in Italy from children hospitalised with AGE; the viruses were genotyped following standard European protocols. Results This 3-year study revealed an overall predominance of the G12P[8] genotype (544 of 2,202 cases; 24.70%), followed by G9P[8] (535/2,202; 24.30%), G1P[8] (459/2,202; 20.84%) and G4P[8] (371/2,202; 16.85%). G2P[4] and G3P[8] genotypes were detected at low rates (3.32% and 3.09%, respectively). Mixed infections accounted for 6.49% of cases (143/2,202), uncommon RVA strains for 0.41% of cases (9/2,202). Conclusions The emergence of G12P[8] rotavirus in Italy, as in other countries, marks this genotype as the sixth most common human genotype. Continuous surveillance of RVA strains and monitoring of circulating genotypes are important for a better understanding of rotavirus evolution and genotype distribution, particularly regarding strains that may emerge from reassortment events.

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