Davidson H Hamer

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Verified

Davidson verified their affiliation via an institutional email.

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• MD
• Professor at Boston University

The early infant gut microbiota is dominated by bifidobacteria, but there is substantial variation at the (sub)species level. Patterns of postnatal Bifidobacterium subspecies colonization in low or middle-income countries have not been widely studied. We used (sub)species-specific qPCR to quantify B. infantis, B. longum , and B. breve in stool samp...

Antimicrobial resistance (AMR) is a global health challenge and there is increasing recognition of the role of the environment, particularly wastewater, in the development and spread of AMR. Although trace metals are common contaminants in wastewater, the quantitative effects of trace metals on AMR in wastewater settings remain understudied. We exp...

Background Children with human immunodeficiency virus (HIV) infection are disproportionately susceptible to bacterial infections. There are a wide range of antibacterial agents available to manage HIV positive children with bacterial infections. However, administration of antibiotics in most children is empirical which could lead to antimicrobial r...

Lactiplantibacillus plantarum ATCC 202195 (LP202195) plus fructooligosaccharide (FOS) for 7 days was previously shown to colonize the infant intestine up to 6 months of age and reduced sepsis rates among young infants in rural India. In a phase 2 randomized controlled trial in Dhaka, Bangladesh ( N = 519), neonatal administration of LP202195 for 1...

Background Understanding factors affecting adoption of an innovation is critical to its long-term success. Maternity waiting homes (MWHs) increase access to facility-based delivery in low-resourced settings; yet, quality issues deter utilization of this innovative approach. We sought to understand how attributes that are thought to promote diffusio...

Background Chagas disease is a neglected parasitic infection that affects ∼300,000 people in the US, with a prevalence of ∼49 per 100,000 in Massachusetts, USA. Untreated Chagas disease leads to irreversible cardiac morbidity and death in 20-30% of cases, yet < 1% receive antitrypanosomal therapy in the US. We describe Chagas disease epidemiology a...

Background Implementation fidelity measures are critical for understanding complex interventions. Though maternity waiting homes (MWHs) are recommended by the WHO and have been used to help pregnant women access health facilities for decades, a gap exists regarding fidelity studies on MWHs. To better understand intervention outcomes results, we ass...

Infant undernutrition, defined by length‐ and weight‐based indices, is common in low‐ and middle‐income countries (LMICs), but corresponding deficits in head size have received less attention. In a cohort of term newborns in Dhaka, Bangladesh, we compared the severity of deficits (vs. World Health Organization Growth Standards) in head circumferenc...

Spatial modelling was employed to identify high-risk zones for the trans-mission of cutaneous leishmaniasis in hyperendemic urban environments, focusing on Mashhad, Iran. Data analysis from 3,033 CL patients (2016-2020) integrated socio-demographic, environmental, and geological factors using negative binomial regression and the technique for order...

Background. Children younger than 5 years old are a vulnerable group whose growth is affected by nutritional intake. However, few studies have evaluated dietary diversity–a proxy measure of dietary adequacy–among HIV-exposed uninfected (HEU) and HIV-unexposed uninfected (HUU) children in resource-limited settings.Objective. To measure dietary diver...

Notwithstanding the obvious interconnection between humans and the world that they share with non-human inhabitants, the impact of our changing climate on certain aspects of the public health ecosystem has been under-investigated. We briefly describe some of the possible climate-induced changes in the procurement, distribution, access and use of me...

Introduction: We present a robust and up-to-date synthesis of evidence on the effectiveness of interventions to prevent and treat newborn infections in low- and middle-income countries (LMICs). Newborn infection prevention interventions included strategies to reduce antimicrobial resistance (AMR), prevention of healthcare-associated infections (HAI...

Background While diarrhoeal disease remains a leading cause of death in children aged <5 years in low- and middle-income countries (LMICs), it also poses significant health risks for older children, underscoring the importance of our study focusing on children aged <10 years. In this systematic review, we assessed common diarrhoea aetiologies in ch...

Background: The effect of the COVID-19 pandemic on healthcare systems emphasized the need for rapid and effective triage tools to identify patients at risk of severe or fatal infection. Measuring host response markers of inflammation and endothelial activation at clinical presentation may help to inform appropriate triage and care practices in pati...

We used cross-sectional data from 226 patients with monkeypox virus to investigate the association between anatomic exposure site and lesion development. Penile, anorectal, and oral exposures predicted lesion presence at correlating anatomic sites. Exposure site also predicted the first lesion site of the penis and anus.

Introduction: Heterogeneity in definitions of severe infection, sepsis and serious bacterial infection (SBI) in young infants limits the comparability of randomized controlled trials (RCTs) of infection prevention and treatment interventions. To inform the design of severe infection prevention RCTs for young infants in low-resource settings, we est...

Background Menstrual disorders, influenced by dietary habits like high fat intake and low fruit and vegetable consumption, are a global public health issue. This study assessed the prevalence of dysmenorrhea, premenstrual syndrome (PMS), and irregular menstrual cycle (IMC) among female university students in Bangladesh, focusing on food cravings an...

Background As part of the Reengineering Primary Health Care initiative, the South African National Department of Health (NDoH) has committed to expanding access to home-based care provided by community health workers. The NDOH also prioritised Community Health Workers (CHWs) in their agenda to improve child development outcomes in South Africa. How...

Vaccine hesitancy has played a major role in slowing the global COVID-19 response. Using cross-sectional, primarily qualitative data collected in four rural districts in Zambia, we aimed to explore community perceptions of COVID-19 disease and vaccines, including perceived motivators, cues to action, benefits, and barriers to vaccine uptake as guid...

Introduction Sepsis, a condition of global public health concern, is a major cause of morbidity and mortality, especially in patients with underlying HIV infection. This study aims to determine outcomes, aetiology and antibiotic resistance patterns among children with HIV exposure or infection admitted with a clinical presentation suggestive of sep...

The risk of dengue emergence in France this summer is likely and must be considered in preparedness planning. The risk could arise from international visitors but also French travellers returning from epidemic areas. The French preparedness and response plan and the importance of international surveillance after the Olympics are highlighted.

Background Dengue is a leading cause of febrile illness among international travellers. We aimed to describe the epidemiology and clinical characteristics of imported dengue in returning travellers evaluated at GeoSentinel sites from 2007–2022. Methods We retrieved GeoSentinel records of dengue among travellers residing in non-endemic countries. W...

We examined the self-rated competence of Ugandan healthcare workers (HCWs) in obtaining informed consent for autopsies, considering the challenges of low autopsy acceptance rates globally. In September and October 2023, we conducted a nationwide cross-sectional study of HCWs, who provided informed consent to participate and completed an online, sel...

Chagas disease is an underrecognized, chronic, and potentially life-threatening disease caused by the parasite Trypanosoma cruzi . We aimed to improve awareness and screening for Chagas disease among patients from endemic areas using a large safety-net academic hospital system in the United States. We developed an educational intervention consistin...

Background: HIV+-to-HIV+ organ transplantation has demonstrated promise and is now authorized for research purposes in certain countries. However, organ transplan- tation is dependent on the availability of organ donors. We assessed the awareness and willingness to donate organs among people with HIV (PWH) in Uganda. Methods: We conducted a multice...

Anthropometric measures at birth, indexing prenatal growth, are associated with later cognitive development. Children in low- and middle-income countries (LMIC) are at elevated risk for impaired prenatal and early postnatal growth and enduring cognitive deficits. However, the associations of neonatal physical growth with neural activity are not wel...

Dengue is the most prevalent mosquito-borne viral disease in humans, and cases are continuing to rise globally. In particular, islands in the Caribbean have experienced more frequent outbreaks, and all four dengue virus (DENV) serotypes have been reported in the region, leading to hyperendemicity and increased rates of severe disease. However, ther...

Highlight Recent epidemics of dengue and chikungunya have highlighted the urgent need for vaccines to reduce the risk of infection in travellers. Given challenges tracking chikungunya outbreaks in real-time and the widespread resurgence of dengue, broader indications for the use of the new chikungunya and dengue vaccines should be considered.

La Crosse virus (LACV) is an arthropod-borne RNA virus with substantial potential for future spread in North America. La Crosse virus is responsible for La Crosse encephalitis, a leading cause of arboviral encephalitis in children in the United States. Primarily transmitted by Aedes triseriatus (Eastern treehole) mosquitos and amplified by small ma...

Introduction Food security and nutrition have been severely impacted during the COVID-19 pandemic, particularly in low- and middle-income countries (LMICs). We aimed to quantify the impacts of the pandemic on food security and diet diversity within Chilanga District in Zambia and identify target areas for high-impact social protection and safety ne...

Background Limited data exist regarding cardiac manifestations of Chagas disease in migrants living in non-endemic regions. Methods A retrospective cohort analysis of 109 patients with Chagas disease seen at Boston Medical Center (BMC) between January 2016 and January 2023 was performed. Patients were identified by screening and testing migrants f...

We document the development and institutionalization in Zambia of a health innovation for diarrhea treatment aimed at children aged younger than 5 years: a unique oral rehydration salts and zinc (ORSZ) co-pack. Seven recommendations from the World Health Organization/ExpandNet are used retrospectively to analyze and describe the successful scale-up...

The growing complexity of GeoSentinel surveillance data creates opportunities for novel data science-based outbreak detection methods. Challenges may be overcome by effective multidisciplinary collaboration. The early signals generated by outbreak detection methods using GeoSentinel data may influence policymaking, shape public health responses, an...

Objective To describe the mortality risks by fine strata of gestational age and birthweight among 230 679 live births in nine low‐ and middle‐income countries (LMICs) from 2000 to 2017. Design Descriptive multi‐country secondary data analysis. Setting Nine LMICs in sub‐Saharan Africa, Southern and Eastern Asia, and Latin America. Population Live...

Background Chikungunya is an important travel-related disease because of its rapid geographical expansion and potential for prolonged morbidity. Improved understanding of the epidemiology of travel-related chikungunya infections may influence prevention strategies including education and vaccination. Methods We analysed data from travellers with c...

Background:Aspergillosis localized to the kidneys and the urinary tract is uncommon. We conducted a comprehensive systematic review to evaluate risk factors and clinical outcomes of patients with isolated renal and genito-urinary tract aspergillosis. Methods:We systematically searched Medline, CINAHL, Embase, African Journal Online, Google Scholar,...

Background Chagas disease is under-recognized in the United States (US) and little is known about how time spent living in endemic versus non-endemic settings affects features of the disease. Methods We performed a cross-sectional, retrospective analysis of 108 individuals with Chagas disease. Presence of cardiac disease was defined according to t...

Background In 2020–2022, U.S. Major League Soccer (MLS) used SARS-CoV-2 mitigation protocols that included masking, social distancing, avoiding contact with others outside of training and games, testing, quarantine, and isolation. In addition to isolation for those who tested positive, a SARS-CoV-2 genomic sequencing strategy was developed to ident...

Background Universities returned to in-person learning in 2021 while SARS-CoV-2 spread remained high. At the time, it was not clear whether in-person learning would be a source of disease spread. Methods We combined surveillance testing, universal contact tracing, and viral genome sequencing to quantify introductions and identify likely on-campus...

Background Adolescents make up roughly a quarter of the population in Zambia; however, most nutrition-related programming is targeted at the under-five population. Understanding the scale of undernutrition in older children and adolescents is fundamental to alleviating food insecurity and addressing undernutrition across all age groups. Methods A...

Background: Diarrhoea is the second most common cause of death among children under the age of five worldwide. The World Health Organization (WHO) recommends treating diarrhoea with oral rehydration therapy, intravenous fluids for severe dehydration, and zinc supplements. Antibiotics are only recommended to treat acute, invasive diarrhoea. Rising...

Problem/condition: During 2012-2021, the volume of international travel reached record highs and lows. This period also was marked by the emergence or large outbreaks of multiple infectious diseases (e.g., Zika virus, yellow fever, and COVID-19). Over time, the growing ease and increased frequency of travel has resulted in the unprecedented global...

Background: The Sepsis Prevention in Neonates in Zambia study is a prospective cohort study that evaluated an infection prevention and control (IPC) bundle in the University Teaching Hospital neonatal intensive care unit (NICU) in Lusaka, Zambia. We present here the etiologies, antimicrobial resistance profiles, and associated mortality of bloodst...

Background: Dengue virus is a flavivirus transmitted by Aedes mosquitoes and is an important cause of illness worldwide. Data on the severity of travel-associated dengue illness are limited. Objective: To describe the epidemiology, clinical characteristics, and outcomes among international travelers with severe dengue or dengue with warning sign...

Antimicrobial resistance (AMR) is a global health challenge and there is increasing recognition of the role of the environment, particularly wastewater, in the development and spread of AMR. Although trace metals are common contaminants in wastewater, the quantitative effects of trace metals on AMR in wastewater settings remain understudied. We exp...

Zika virus is a mosquito‐borne flavivirus which caused major epidemics in the Pacific and the Americas between 2013 and 2015. International travellers have previously acted as a sentinel population for Zika virus transmission in endemic areas, where local transmission may be incompletely captured by local surveillance systems. We report five recent...

In early 2020, the Zambian Ministry of Health instituted prevention guidelines to limit spread of COVID-19. We assessed community knowledge, motivations, behavioral skills, and perceived community adherence to prevention behaviors (i.e., hand hygiene, mask wearing, social distancing, and limiting gatherings). Within a cluster-randomized controlled...

Despite reductions in the number of under-five deaths since the release of the Sustainable Development Goals, the proportion of neonatal deaths among all under-five deaths has remained high. Neonatal health is linked to newborn care practices which are tied to distinct cultural perceptions of health and illness. We assessed how community beliefs in...

Background Cutaneous leishmaniasis (CL) is a wide-reaching infection of major public health concern. Iran is one of the six most endemic countries in the world. This study aims to provide a spatiotemporal visualization of CL cases in Iran at the county level from 2011 to 2020, detecting high-risk zones, while also noting the movement of high-risk c...

Objective: We aimed to understand the mortality risks of vulnerable newborns (defined as preterm and/or born weighing smaller or larger compared to a standard population), in low- and middle-income countries (LMICs). Design: Descriptive multi-country, secondary analysis of individual-level study data of babies born since 2000. Setting: Sixteen...

Objective: To examine prevalence of novel newborn types among 541 285 live births in 23 countries from 2000 to 2021. Design: Descriptive multi-country secondary data analysis. Setting: Subnational, population-based birth cohort studies (n = 45) in 23 low- and middle-income countries (LMICs) spanning 2000-2021. Population: Liveborn infants....

To examine prevalence of novel newborn types among 541 285 live births in 23 countries from 2000 to 2021.

Background Professional soccer athletes are at risk of acquiring SARS-CoV-2 when traveling or through domestic community transmission. The U.S. Major League Soccer (MLS) league uses protocol-based SARS-CoV-2 testing for identification of individuals with COVID-19. Methods Per MLS protocol, fully vaccinated players underwent SARS-CoV-2 RT-PCR testi...

Background: International travellers frequently acquire infectious diseases while travelling, yet relatively little is known about the impact and economic burden of these illnesses on travellers. We conducted a prospective exploratory costing study on adult returning travellers with falciparum malaria, dengue, chikungunya, or Zika virus. Methods:...

Small newborns are vulnerable to mortality and lifelong loss of human capital. Measures of vulnerability previously focused on liveborn low-birthweight (LBW) babies, yet LBW reduction targets are off-track. There are two pathways to LBW, preterm birth and fetal growth restriction (FGR), with the FGR pathway resulting in the baby being small for ges...

Introduction: Early reading interventions hold promise for increasing language and literacy development in young children and improving caregiver-child interactions. To engage rural caregivers and young children in home reading, Zambian child psychologists and education specialists developed a culturally representative, local language children's b...

Background Effective integration of home visit interventions focused on early childhood development into existing service platforms is important for expanding access in low- and middle-income countries (LMICs). We designed and evaluated a home visit intervention integrated into community health worker (CHW) operations in South Africa. Methods and...

Maternity waiting homes (MWHs) are one strategy to improve access to skilled obstetric care in low resource settings such as Zambia. The Maternity Homes Access in Zambia project built 10 MWHs at rural health centers in Zambia for women awaiting delivery and postnatal care (PNC) visits. The objective of this paper is to summarize the costs associate...

Deficiency of essential trace element, selenium, has been implicated in adverse birth outcomes and in child linear growth because of its important role in redox biology and associated antioxidant effects. We used data from a randomized controlled trial conducted among a cohort of pregnant and lactating women in Dhaka, Bangladesh to examine associat...

Background Compared to 2017, India achieved a significant reduction in malaria cases in 2020. Madhya Pradesh (MP) is a tribal dominated state of India with history of high malaria burden in some districts. District Mandla of MP state showed a considerable decline in malaria cases between 2000 and 2013, except in 2007. Subsequently, a resurgence of...

The COVID-19 pandemic has increased social and emotional stressors globally, increasing mental health concerns and the risk of psychiatric illness worldwide. To date, relatively little is known about the impact of the pandemic on vulnerable groups such as women and children in low-resourced settings who generally have limited access to mental healt...

Background Postnatal care (PNC) is an important set of services offered to the mother and her newborn baby immediately after birth for the first six weeks to prevent maternal and neonatal complications and death. This qualitative study explored user and provider perspectives on quality of PNC services in the selected health facilities within the co...

Travelers to Chagas disease endemic regions of Latin America may be at risk for Trypanosoma cruzi infection. We report a 67-year-old woman who screened positive for T. cruzi infection while donating blood. The patient had a history of an unusual febrile illness and marked swelling of the face sustained at age 10 after camping in northern Mexico tha...

Background: International travellers may seek care abroad to address health problems that arise during their trip or plan healthcare outside their country of residence as medical tourists. Methods: Data were collected on travellers evaluated at GeoSentinel Network sites who reported healthcare during travel. Both unplanned and planned healthcare...

A growing body of evidence shows that early child development varies along a socioeconomic gradient, with poorest outcomes observed in chil- dren from the most disadvantaged environments in low-income countries. Most of this evidence comes from studies using caregiver reports or expert judgments of child behavior. We used eye tracking to examine wh...

Guidelines for improving future preparedness and response to infectious diseases.

Infection remains an important cause of maternal and newborn morbidity and mortality globally despite evidence that it can be reduced with adherence to infection prevention and control (IPC) practices. The implementation of IPC has been especially challenging in rural health centres. This pilot study used a non-randomised quasi-experimental design...

Highlight Increasing numbers of travellers returning from Cuba with dengue virus infection were reported to the GeoSentinel Network from June through September 2022, reflecting an ongoing local outbreak. This report demonstrates the importance of travellers as sentinels of arboviral outbreaks and highlights the need for early identification of trav...

Background Omicron rapidly replaced delta as the predominant strain causing COVID-19 related illness in the United States (US) in December 2021, the same month the US CDC reduced the recommended isolation period from 10 to 5 days for asymptomatic individuals or those with resolving symptoms. New evidence suggests some asymptomatic individuals with...

Background Vaccination is a fundamental element of pandemic control; however, insufficient data exists on vaccine’s impact on SARS-CoV-2 viral dynamics. We aimed to evaluate the relationship between time to negative viral culture conversion after diagnosis and time since most recent COVID-19 vaccination. Scatterplot illustrating relationship betwee...

Zambia instituted prevention behavior guidelines for social gatherings before the first case of COVID-19 was confirmed on March 18, 2020. Guidelines included nonpharmaceutical interventions (NPIs) including mask wearing, social distancing, and reducing sizes of gatherings. Within a larger cluster randomized trial of community-based parenting groups...

Purpose Whether anemia type modifies the risk of pregnancy and newborn outcomes and the effectiveness of iron supplementation is unclear. We examined the association of iron deficiency anemia (IDA) and non-iron deficiency anemia (NIDA) on the risks of these outcomes and the extent to which anemia type modifies the impact of prenatal iron supplement...

Deficiency of selenium, an essential trace element, has been implicated in adverse birth outcomes and the growth of infants and young children. We used data from a randomized controlled trial to examine associations between selenium biomarkers in whole blood (WBSe), serum and selenoprotein P (SEPP1) in maternal delivery and venous cord (VC) blood,...