Low frequency of enterohemorrhagic, enteroinvasive and diffusely adherent Escherichia coli in children under 5 years in rural Mozambique: a case-control study

BACKGROUND NlmCategory: BACKGROUND content: Diarrheagenic Escherichia coli (DEC) are among the leading pathogens associated with endemic diarrhea in low income countries. Yet, few epidemiological studies have focused the contribution of enterohemorrhagic E. coli (EHEC), enteroinvasive E. coli (EIEC) and diffusely adherent E. coli (DAEC). - Label: METHODS NlmCategory: METHODS content: "We assessed the contribution of EHEC, EIEC and DAEC isolated from stool samples from a case-control study conducted in children aged <\xE2\x80\x895\xE2\x80\x89years in Southern Mozambique between December 2007 and November 2012. The isolates were screened by conventional PCR targeting stx1 and stx2 (EHEC), ial and ipaH (EIEC), and daaE (DAEC) genes." - Label: RESULTS NlmCategory: RESULTS content: "We analyzed 297 samples from cases with less-severe diarrhea (LSD) matched to 297 controls, and 89 samples from cases with moderate-to-severe diarrhea (MSD) matched to 222 controls, collected between November 3, 2011 and November 2, 2012. DEC were more common among LSD cases (2.7%, [8/297] of cases vs. 1.3% [4/297] of controls; p\xC2\xA0=\xE2\x80\x890.243]) than in MSD cases (0%, [0/89] of cases vs. 0.4%, [1/222]\xC2\xA0of controls; p\xC2\xA0=\xE2\x80\x891.000). Detailed analysis revealed low frequency of EHEC, DAEC or EIEC and no association with diarrhea in all age strata. Although the low frequency, EIEC was predominant in LSD cases aged 24-59\xE2\x80\x89months (4.1% for cases vs. 0% for controls), followed by DAEC in similar frequency for cases and controls in infants (1.9%) and lastly EHEC from one control. Analysis of a subset of samples from previous period (December 10, 2007 and October 31, 2011) showed high frequency of DEC in controls compared to MSD cases (16.2%, [25/154] vs. 11.9%, [14/118], p\xC2\xA0=\xE2\x80\x890.383, respectively). Among these, DAEC predominated, being detected in 7.7% of cases vs. 17.6% of controls aged 24-59\xE2\x80\x89months, followed by EIEC in 7.7% of cases vs. 5.9% of controls for the same age category, although no association was observed. EHEC was detected in one sample from cases and two from controls." - Label: CONCLUSIONS NlmCategory: CONCLUSIONS content: Our data suggests that although EHEC, DAEC and EIEC are less frequent in endemic diarrhea in rural Mozambique, attention should be given to their transmission dynamics (e.g. the role on sporadic or epidemic diarrhea) considering that the role of asymptomatic individuals as source of dissemination remains unknown

Molecular Epidemiology of Rotavirus Strains in Symptomatic and Asymptomatic Children in Manhiça District, Southern Mozambique 2008–2019

..870-15 SC; the United States Agency for International Development (USAID), grant number AID-656-F-16-00002 and Fundo Nacional de Investiga??o (FNI), Mo?ambique, grant number 245-INV, within the context of diarrhoeal disease surveillance platform implementation. F.M PhD is supported by Calouste Gulbenkian Foundation, grant number 234066. The authors convey many thanks to all the caregivers who consented to their children?s participation in both studies (GEMS and the diarrhoeal disease platform). They would also like to thank all the professionals in the hospitals and those on field recruitment for their full dedication and effort in children enrolment and collection of data and samples whenever possible. Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Group A rotaviruses remain the leading cause of diarrhoea in children aged <5 years. Mozambique introduced rotavirus vaccine (Rotarix® ) in September 2015. We report rotavirus geno-types circulating among symptomatic and asymptomatic children in Manhiça District, Mozambique, pre-and post-vaccine introduction. Stool was collected from enrolled children and screened for ro-tavirus by enzyme-immuno-sorbent assay. Positive specimens were genotyped for VP7 (G genotypes) and VP4 (P genotypes) by the conventional reverse transcriptase polymerase chain reaction. The combination G12P[8] was more frequently observed in pre-vaccine than in post-vaccine introduction, in moderate to severe diarrhoea (34%, 61/177 vs. 0, p < 0.0001) and controls (23%, 26/113 vs. 0, p = 0.0013) and mixed genotypes (36%, 24/67 vs. 7% 4/58, p = 0.0003) in less severe diarrhoea. We observed changes in post-vaccine compared to pre-vaccine introduction, where G3P[4] and G3P[8] were prevalent in moderate to severe diarrhoea (10%, 5/49 vs. 0, p = 0.0002; and 14%, 7/49 vs. 1%, 1/177, p < 0.0001; respectively), and in less severe diarrhoea (21%, 12/58 vs. 0, p = 0.003; and 24%, 14/58 vs. 0, p < 0.0001; respectively). Our surveillance demonstrated the circulation of similar genotypes contemporaneously among cases and controls, as well as switching from pre-to post-vaccine introduction. Continuous surveillance is needed to evaluate the dynamics of the changes in genotypes following vaccine introduction.publishersversionpublishe

Genomic characterization of the rotavirus G3P[8] strain in vaccinated children, reveals possible reassortment events between human and animal strains in Manhiça District, Mozambique

Mozambique introduced the rotavirus vaccine (Rotarix®; GlaxoSmithKline Biologicals, Rixensart, Belgium) in 2015, and since then, the Centro de Investigação em Saúde de Manhiça has been monitoring its impact on rotavirus-associated diarrhea and the trend of circulating strains, where G3P[8] was reported as the predominant strain after the vaccine introduction. Genotype G3 is among the most commonly detected Rotavirus strains in humans and animals, and herein, we report on the whole genome constellation of G3P[8] detected in two children (aged 18 months old) hospitalized with moderate-to-severe diarrhea at the Manhiça District Hospital. The two strains had a typical Wa-like genome constellation (I1-R1-C1-M1-A1-N1-T1-E1-H1) and shared 100% nucleotide (nt) and amino acid (aa) identities in 10 gene segments, except for VP6. Phylogenetic analysis demonstrated that genome segments encoding VP7, VP6, VP1, NSP3, and NSP4 of the two strains clustered most closely with porcine, bovine, and equine strains with identities ranging from 86.9–99.9% nt and 97.2–100% aa. Moreover, they consistently formed distinct clusters with some G1P[8], G3P[8], G9P[8], G12P[6], and G12P[8] strains circulating from 2012 to 2019 in Africa (Mozambique, Kenya, Rwanda, and Malawi) and Asia (Japan, China, and India) in genome segments encoding six proteins (VP2, VP3, NSP1-NSP2, NSP5/6). The identification of segments exhibiting the closest relationships with animal strains shows significant diversity of rotavirus and suggests the possible occurrence of reassortment events between human and animal strains. This demonstrates the importance of applying next-generation sequencing to monitor and understand the evolutionary changes of strains and evaluate the impact of vaccines on strain diversity

Genomic characterization of the rotavirus G3P[8] strain in vaccinated children, reveals possible reassortment events between human and animal strains in Manhiça District, Mozambique

870–15 SC; the United States Agency for International Development (USAID), grant number AID-656-F-16-00002 and Fundo Nacional de Investigação (FNI), Moçambique, grant number 245-INV, funded the surveillance of rotavirus and other enteropathogens in children less than 5 years of age in Manhiça, in the context of the implementation of the diarrhoeal disease surveillance platform. The Child Health and Mortality Prevention program (Surveillance), CHAMPS funded by the Bill & Melinda Gates Foundation under Grant OPP1126780, the Instituto de Higiene e Medicina Tropical (IHMT), Universidade Nova de Lisboa, Portugal, the Next Generation Sequencing Unit, and the Division of Virology, Faculty of Health Sciences, University of the Free State, South Africa, supported the whole genome analysis costs. The Calouste Gulbenkian Foundation finances Filomena Manjate’s Ph.D. studies under grant number 234066. CISM receives core funding from the Mozambican government and the “Agencia Española de Cooperacion Internacional para el Desarollo (AECID).” Publisher Copyright: Copyright © 2023 Manjate, João, Mwangi, Chirinda, Mogotsi, Messa, Garrine, Vubil, Nobela, Nhampossa, Acácio, Tate, Parashar, Weldegebriel, Mwenda, Alonso, Cunha, Nyaga and Mandomando.Mozambique introduced the rotavirus vaccine (Rotarix®; GlaxoSmithKline Biologicals, Rixensart, Belgium) in 2015, and since then, the Centro de Investigação em Saúde de Manhiça has been monitoring its impact on rotavirus-associated diarrhea and the trend of circulating strains, where G3P[8] was reported as the predominant strain after the vaccine introduction. Genotype G3 is among the most commonly detected Rotavirus strains in humans and animals, and herein, we report on the whole genome constellation of G3P[8] detected in two children (aged 18 months old) hospitalized with moderate-to-severe diarrhea at the Manhiça District Hospital. The two strains had a typical Wa-like genome constellation (I1-R1-C1-M1-A1-N1-T1-E1-H1) and shared 100% nucleotide (nt) and amino acid (aa) identities in 10 gene segments, except for VP6. Phylogenetic analysis demonstrated that genome segments encoding VP7, VP6, VP1, NSP3, and NSP4 of the two strains clustered most closely with porcine, bovine, and equine strains with identities ranging from 86.9–99.9% nt and 97.2–100% aa. Moreover, they consistently formed distinct clusters with some G1P[8], G3P[8], G9P[8], G12P[6], and G12P[8] strains circulating from 2012 to 2019 in Africa (Mozambique, Kenya, Rwanda, and Malawi) and Asia (Japan, China, and India) in genome segments encoding six proteins (VP2, VP3, NSP1-NSP2, NSP5/6). The identification of segments exhibiting the closest relationships with animal strains shows significant diversity of rotavirus and suggests the possible occurrence of reassortment events between human and animal strains. This demonstrates the importance of applying next-generation sequencing to monitor and understand the evolutionary changes of strains and evaluate the impact of vaccines on strain diversity.publishersversionpublishe