Rotavirus-Specific Maternal Serum Antibodies and Vaccine Responses to RV3-BB Rotavirus Vaccine Administered in a Neonatal or Infant Schedule in Malawi.

High titres of rotavirus-specific maternal antibodies may contribute to lower rotavirus vaccine efficacy in low- and middle-income countries (LMICs). RV3-BB vaccine (G3P[6]) is based on a neonatal rotavirus strain that replicates well in the newborn gut in the presence of breast milk. This study investigated the association between maternal serum antibodies and vaccine response in infants administered the RV3-BB vaccine.

Impact of rotavirus vaccination in Malawi from 2012 to 2022 compared to model predictions before, during, and after the COVID-19 pandemic.

Background: Rotarix rotavirus vaccine was introduced into the Malawi national immunization program in October 2012. We used a previously developed mathematical models to estimate overall vaccine effectiveness over a 10-year period following rotavirus vaccine introduction.

Methods: We analyzed data on children <5 years old hospitalized with acute gastroenteritis in Blantyre, Malawi from January 2012 to June 2022, compared to pre-vaccination data.

Diarrhea Case Surveillance in the Enterics for Global Health Surveillance Study: Epidemiologic Methods.

Background: is a leading cause of acute watery diarrhea, dysentery, and diarrhea-attributed linear growth faltering, a precursor to stunting and lifelong morbidity. Several promising vaccines are in development and field efficacy trials will require a consortium of potential vaccine trial sites with up-to-date diarrhea incidence data.

Methods: The Enterics for Global Health (EFGH) surveillance study will employ facility-based enrollment of diarrhea cases aged 6-35 months with 3 months of follow-up to establish incidence rates and document clinical, anthropometric, and financial consequences of diarrhea at 7 country sites (Mali, Kenya, The Gambia, Malawi, Bangladesh, Pakistan, and Peru).

The Enterics for Global Health (EFGH) Surveillance Study in Malawi.

Background: Malawi is among 7 countries participating in the Enterics for Global Health (EFGH) surveillance study, which aims to determine the incidence of medically attended diarrhea attributed to , a leading bacterial cause of diarrhea in children in low-resource settings.

Methods: We describe the EFGH study site in the densely populated informal settlement of Ndirande Township, Blantyre, Malawi. We explore the site's geographical location, demographic characteristics, and the healthcare-seeking behavior of its population, particularly for childhood diarrhea.

Microbiological Methods Used in the Enterics for Global Health Surveillance Study.

Background: is a major cause of diarrhea in young children worldwide. Multiple vaccines targeting are in development, and phase 3 clinical trials are imminent to determine efficacy against shigellosis.

Methods: The Enterics for Global Health (EFGH) surveillance study is designed to determine the incidence of medically attended shigellosis in 6- to 35-month-old children in 7 resource-limited settings.

Utilizing river and wastewater as a SARS-CoV-2 surveillance tool in settings with limited formal sewage systems.

The COVID-19 pandemic has profoundly impacted health systems globally and robust surveillance has been critical for pandemic control, however not all countries can currently sustain community pathogen surveillance programs. Wastewater surveillance has proven valuable in high-income settings, but less is known about the utility of water surveillance of pathogens in low-income countries. Here we show how wastewater surveillance of SAR-CoV-2 can be used to identify temporal changes and help determine circulating variants quickly.

Increased bacterial taxonomic and functional diversity is associated with impaired rotavirus vaccine immunogenicity in infants from India and Malawi.

The immunogenicity and effectiveness of oral rotavirus vaccines (ORVs) against severe rotavirus-associated gastroenteritis are impaired in low- and middle-income countries (LMICs) where the burden of disease is highest. Determining risk factors for impaired ORV response may help identify strategies to enhance vaccine effectiveness. In this study, we use metagenomic sequencing to provide a high-resolution taxonomic analysis of stool samples collected at 6 weeks of age (coinciding with the first ORV dose) during a prospective study of ORV immunogenicity in India and Malawi.

Draft genomes of from patients with cholera-like illness during the 2022-2023 cholera outbreak in Malawi.

is an increasingly recognized etiological agent of acute gastroenteritis. Here, we report five draft genomes of isolated from suspected cholera cases during the 2022-2023 cholera outbreak in Malawi.

Association Between Maternal Breastmilk Microbiota Composition and Rotavirus Vaccine Response in African, Asian, and European Infants: A Prospective Cohort Study.

Background: Maternal breastmilk is a source of pre- and pro-biotics that impact neonatal gut microbiota colonization. Because oral rotavirus vaccines (ORVs) are administered at a time when infants are often breastfed, breastmilk microbiota composition may have a direct or indirect influence on vaccine take and immunogenicity.

Methods: Using standardized methods across sites, we compared breastmilk microbiota composition in relation to geographic location and ORV response in cohorts prospectively followed from birth to 18 weeks of age in India (n = 307), Malawi (n = 119), and the United Kingdom ([UK] n = 60).

Comparative whole genome analysis reveals re-emergence of human Wa-like and DS-1-like G3 rotaviruses after Rotarix vaccine introduction in Malawi.

G3 rotaviruses rank among the most common rotavirus strains worldwide in humans and animals. However, despite a robust long-term rotavirus surveillance system from 1997 at Queen Elizabeth Central Hospital in Blantyre, Malawi, these strains were only detected from 1997 to 1999 and then disappeared and re-emerged in 2017, 5 years after the introduction of the Rotarix rotavirus vaccine. Here, we analysed representative twenty-seven whole genome sequences (G3P[4], = 20; G3P[6], = 1; and G3P[8], = 6) randomly selected each month between November 2017 and August 2019 to understand how G3 strains re-emerged in Malawi.

Utilizing river and wastewater as a SARS-CoV-2 surveillance tool to predict trends and identify variants of concern in settings with limited formal sewage systems.

The COVID-19 pandemic continues to impact health systems globally and robust surveillance is critical for pandemic control, however not all countries can sustain community surveillance programs. Wastewater surveillance has proven valuable in high-income settings, but little is known about how river and informal sewage in low-income countries can be used for environmental surveillance of SARS-CoV-2. In Malawi, a country with limited community-based COVID-19 testing capacity, we explored the utility of rivers and wastewater for SARS-CoV-2 surveillance.

Co-Surveillance of Rotaviruses in Humans and Domestic Animals in Central Uganda Reveals Circulation of Wide Genotype Diversity in the Animals.

Rotavirus genotypes are species specific. However, interspecies transmission is reported to result in the emergence of new genotypes. A cross-sectional study of 242 households with 281 cattle, 418 goats, 438 pigs, and 258 humans in Uganda was undertaken between 2013 and 2014.

Omicron B.1.1.529 variant infections associated with severe disease are uncommon in a COVID-19 under-vaccinated, high SARS-CoV-2 seroprevalence population in Malawi.

Background: The B.1.1.

Evolutionary changes between pre- and post-vaccine South African group A G2P[4] rotavirus strains, 2003-2017.

The transient upsurge of G2P[4] group A rotavirus (RVA) after Rotarix vaccine introduction in several countries has been a matter of concern. To gain insight into the diversity and evolution of G2P[4] strains in South Africa pre- and post-RVA vaccination introduction, whole-genome sequencing was performed for RVA positive faecal specimens collected between 2003 and 2017 and samples previously sequenced were obtained from GenBank (=103; 56 pre- and 47 post-vaccine). Pre-vaccine G2 sequences predominantly clustered within sub-lineage IVa-1.

AstraZeneca COVID-19 vaccine induces robust broadly cross-reactive antibody responses in Malawian adults previously infected with SARS-CoV-2.

Background: Binding and neutralising anti-Spike antibodies play a key role in immune defence against SARS-CoV-2 infection. Since it is known that antibodies wane with time and new immune-evasive variants are emerging, we aimed to assess the dynamics of anti-Spike antibodies in an African adult population with prior SARS-CoV-2 infection and to determine the effect of subsequent COVID-19 vaccination.

Methods: Using a prospective cohort design, we recruited adults with prior laboratory-confirmed mild/moderate COVID-19 in Blantyre, Malawi, and followed them up for 270 days (n = 52).