A cross-sectional study in four provinces of Mozambique: Diarrheagenic Escherichia coli in Mozambique

Funding Information: The National Surveillance of Diarrhea was supported by a Senior Fellowship awarded to Nilsa de Deus by the European Foundations Initiative for African Research into Neglected Tropical Diseases (EFINTD, grant number 98539), the World Health Organization, a Master Fellowship funded by the Italian Agency for Development Cooperation (AICS) project AID10524, Deutsche Forschungsgemeinschaft (DFG, grant number JO369/5–1)—where Adilson Fernando Loforte Bauhofer and Assucênio Chissaque are fellows, GAVI (Global Alliance for Vaccines and Immunization) through Health System Strengthening (HSS), and Fundo Nacional de Investigação (FNI). The protocol was approved by the National Bioethics Committee for Health of Mozambique (IRB00002657, reference number: 348/CNBS/13), and each caregiver gave written informed consent to authorize their child's participation. The authors want to thank the parents or guardians who consented to their children's enrollment in the surveillance program. The authors acknowledge Dr. Octávio Jossai, the National Reference Laboratory of Microbiology team, all the focal points, and the provincial field teams who helped to conduct this study. Funding Information: The National Surveillance of Diarrhea was supported by a Senior Fellowship awarded to Nilsa de Deus by the European Foundations Initiative for African Research into Neglected Tropical Diseases (EFINTD, grant number 98539), the World Health Organization, a Master Fellowship funded by the Italian Agency for Development Cooperation (AICS) project AID10524, Deutsche Forschungsgemeinschaft (DFG, grant number JO369/5–1)—where Adilson Fernando Loforte Bauhofer and Assucênio Chissaque are fellows, GAVI (Global Alliance for Vaccines and Immunization) through Health System Strengthening (HSS), and Fundo Nacional de Investigação (FNI). Publisher Copyright: © 2022Objectives: Analyze the frequency of diarrheagenic Escherichia coli (DEC) pathotypes and their antimicrobial resistance profiles among children aged <15 years with diarrhea in four Mozambican provinces. Methods: A cross-sectional hospital-based surveillance program of diarrhea was implemented in Maputo, Sofala, Zambézia, and Nampula. A single stool sample was collected from each child from May 2014 to May 2017. Culture methods and biochemical characterization were performed to detect E. coli strains. DEC pathotypes were determined by conventional polymerase chain reaction targeting specific virulence genes. Antimicrobial susceptibility was assessed by the Kirby–Bauer method. Results: From 723 specimens analyzed by culture, 262 were positive for E. coli. A total of 208 samples were tested by polymerase chain reaction for DEC identification, of which 101 (48.6%) were positive for a DEC pathotype. The predominant pathotypes were enteroaggregative (66.3%, 67/101), enteropathogenic (15.8%, 16/101), enterotoxigenic (13.9%, 14/101), and enteroinvasive E. coli (4.0%, 4/101). No Shiga toxin–producing E. coli was identified. Regardless of the province, the most frequent pathotype was enteroaggregative E. coli. Isolated DEC presented high frequency of resistance to ampicillin (97.8%), tetracycline (68.3%), chloramphenicol (28.4%), nalidixic acid (19.5%), and gentamicin (14.4%). Conclusion: Children with diarrhea in Mozambique had DEC and higher resistance to ampicillin and tetracycline.publishersversionpublishe

Antigenic and genetic characterization of influenza viruses isolated in Mozambique during the 2015 season.

BACKGROUND:Due to the high rate of antigenic variation of influenza virus, seasonal characterization of the virus is crucial to assess and monitor the emergence of new pathogenic variants and hence formulate effective control measures. However, no study has yet been conducted in Mozambique to assess genetic, antigenic and antiviral susceptibility profile of influenza virus. METHODS:A subset of samples (n = 20) from influenza positive children detected in two hospitals in Maputo city during 2015 season as part of the implementation of influenza surveillance system, were selected. The following assays were performed on these samples: antigenic characterization by hemagglutination inhibition assay, genetic characterization by Sanger sequencing of hemagglutinin (HA) and neuraminidase (NA) and susceptibility to oseltamivir and zanamivir (NA inhibitors) by enzymatic assay. RESULTS:The A(H1N1)pdm09 subtype viruses remained closely related antigenically and genetically to the 2016 vaccine virus A/California/7/2009 and other widely distributed viruses belonging to genetic group 6B. The majority of influenza A(H3N2) viruses studied were antigenically similar to the 2016-2017 vaccine virus, A/Hong Kong/4801/2014, and their HA and NA gene sequences fell into genetic subclade 3C.2a being closely related to viruses circulating in southern Africa. The influenza B viruses were antigenically similar to the 2016 season vaccine virus and HA sequences of all three fell into the B/Yamagata-lineage, clade 3, but contained NA genes of the B/Victoria-lineage. All tested viruses were sensitive to oseltamivir and zanamivir. CONCLUSION:Overall, all Mozambican influenza A and B viruses were most closely related to Southern African viruses and all were sensitive to oseltamivir and zanamivir. These findings suggest the existence of an ecological niche of influenza viruses within the region and hence highlighting the need for joint epidemiologic and virologic surveillance to monitor the evolution of influenza viruses

Antigenic (HI) analyses of A(H1N1)pdm09 viruses.

<p>Antigenic (HI) analyses of A(H1N1)pdm09 viruses.</p

Phylogenetic comparison of influenza A(H3N2) HA genes.

<p>The month of clinical specimen collection is indicated by colour (March to July 2015) after each virus name. Specific viruses are highlighted: vaccine virus (bold red), reference viruses to which post-infection ferret antisera were raised (bold black) and Mozambican viruses (boxed). Amino acid substitutions defining specific genetic clusters are indicated at nodes and virus-specific substitutions are shown after the virus name (* indicates polymorphism). Genetic clades and subclades are indicated at the right of the tree and the scale bar indicates the distance between isolates.</p

Antigenic (HI) analyses of A(H3N2) viruses (guinea pig RBCs in the presence of 20 nM oseltamivir).

<p>Antigenic (HI) analyses of A(H3N2) viruses (guinea pig RBCs in the presence of 20 nM oseltamivir).</p

Antigenic (HI) analyses of influenza B viruses.

<p>Antigenic (HI) analyses of influenza B viruses.</p

General characteristics of the participants analyzed in this study.

<p>General characteristics of the participants analyzed in this study.</p

Phylogenetic comparison of influenza A(H1N1)pdm09 HA genes.

<p>The month of clinical specimen collection is indicated by colour (April to July 2015) and after each virus name. Specific viruses are highlighted: vaccine virus (bold red), reference viruses to which post-infection ferret antisera were raised (bold black) and Mozambican viruses (boxed). Amino acid substitutions defining specific genetic clusters are indicated at nodes and virus-specific substitutions are shown after the virus name (* indicates polymorphism). Genetic group 6B, defined by HA1 amino acid substitutions K163Q and A256T, is indicated and the scale bar indicates the distance between isolates.</p

Clinical and epidemiological characterization of influenza virus infections in children with severe acute respiratory infection in Maputo, Mozambique: Results from the implementation of sentinel surveillance, 2014 – 2016

<div><p>In Sub-Saharan Africa, where burden, impact, and incidence of acute respiratory infections (ARI) are the highest in the world, conversely, the epidemiology of influenza-associated severe acute respiratory infections (SARI) is incompletely known. The aim of this study was to describe the clinical and epidemiological features of influenza-associated SARI in hospitalized children in Maputo city, Mozambique. Nasopharyngeal and oropharyngeal swabs were collected from children aged 0–14 years old who met the case definition for SARI in two hospitals in Maputo city after their parents or legal representative consented to participate. A structured questionnaire was used to collect clinical and demographic data. Typing and subtyping of influenza were performed by real-time PCR. From January 2014 to December 2016, a total of 2,007 eligible children were recruited, of whom 1,997 (99.5%) were screened for influenza by real-time PCR. The median age of participants was 16.9 months (IQR: 7.0–38.9 months) and 53.9% (1076/1991) were male. A total of 77 were positive for influenza, yielding a frequency of 3.9% (77/1,991), with the highest frequency being reported in the age group 1–5 years old. Cases of influenza peaked twice each year, during which, its frequency reached up to 60%-80%. Among all influenza confirmed cases, 33.7% (26/77), 35.1% (27/77) and 28.6% (22/77) were typed as influenza A/H3N2, A/H1N1pdm09, and B, respectively. This represents the first report of influenza in urban/sub urban setting in Mozambique and the first evidence of distribution of strains of influenza in the country. Our data showed that frequency of influenza was lower than reported in a rural setting in Mozambique and the frequency of seasonal (A/H1N1pdm09) and (A/H3N2) subtypes were similar in children with SARI.</p></div

Monthly variation of influenza virus types and subtypes and positivity rates from January 2014 to December 2016.

<p>Nasopharyngeal and oropharyngeal swabs from children admitted with SARI were tested for Influenza virus using RT-PCR.</p