ABSTRACT
OBJECTIVE: To examine internal organ tissues and placentas of stillbirths for various pathogens. DESIGN: Prospective, observational study. SETTINGS: Three study hospitals in India and a large maternity hospital in Pakistan. POPULATION: Stillborn infants delivered in a study hospital. METHODS: A prospective observational study. MAIN OUTCOME MEASURES: Organisms identified by pathogen polymerase chain reaction (PCR) in internal organs and placental tissues of stillbirths. RESULTS: Of 2437 stillbirth internal tissues, 8.3% (95% CI 7.2-9.4) were positive. Organisms were most commonly detected in brain (12.3%), cerebrospinal fluid (CSF) (9.5%) and whole blood (8.4%). Ureaplasma urealyticum/parvum was the organism most frequently detected in at least one internal organ (6.4% of stillbirths and 2% of all tissues). Escherichia coli/Shigella was the next most common (4.1% one or more internal organ tissue sample and 1.3% of tissue samples), followed by Staphylococcus aureus in at least one internal organ tissue (1.9% and 0.9% of all tissues). None of the other organisms was found in more than 1.4% of the tissue samples in stillbirths or more than 0.6% of the internal tissues examined. In the placenta tissue, membrane or cord blood combined, 42.8% (95% CI 40.2-45.3) had at least one organism identified, with U. urealyticum/parvum representing the most commonly identified (27.8%). CONCLUSIONS: In about 8% of stillbirths, there was evidence of a pathogen in an internal organ. Ureaplasma urealyticum/parvum was the most common organism found in the placenta and in the internal tissues, especially in the fetal brain.
Subject(s)
Placenta , Stillbirth , Infant , Pregnancy , Female , Humans , Stillbirth/epidemiology , Prospective Studies , Ureaplasma , BrainABSTRACT
BACKGROUND: We identified pathogens found in internal organs and placentas of deceased preterm infants cared for in hospitals in India and Pakistan. METHODS: Prospective, observational study conducted in delivery units and neonatal intensive care units. Tissue samples from deceased neonates obtained by minimally invasive tissue sampling and placentas were examined for 73 different pathogens using multiplex polymerase chain reaction (PCR). RESULTS: Tissue for pathogen PCR was obtained from liver, lung, brain, blood, cerebrospinal fluid, and placentas from 377 deceased preterm infants. Between 17.6% and 34.1% of each type of tissue had at least 1 organism identified. Organism detection was highest in blood (34.1%), followed by lung (31.1%), liver (23.3%), cerebrospinal fluid (22.3%), and brain (17.6%). A total of 49.7% of the deceased infants had at least 1 organism. Acinetobacter baumannii was in 28.4% of the neonates compared with 14.6% for Klebsiella pneumoniae, 11.9% for Escherichia coli/Shigella, and 11.1% for Haemophilus influenzae. Group B streptococcus was identified in only 1.3% of the neonatal deaths. A. baumannii was rarely found in the placenta and was found more commonly in the internal organs of neonates who died later in the neonatal period. The most common organism found in placentas was Ureaplasma urealyticum in 34% of the samples, with no other organism found in >4% of samples. CONCLUSIONS: In organ samples from deceased infants in India and Pakistan, evaluated with multiplex pathogen PCR, A. baumannii was the most commonly identified organism. Group B streptococcus was rarely found. A. baumannii was rarely found in the placentas of these deceased neonates.
Subject(s)
Perinatal Death , Infant , Pregnancy , Female , Infant, Newborn , Humans , Infant, Premature , Prospective Studies , Pakistan/epidemiology , Multiplex Polymerase Chain Reaction , Escherichia coliABSTRACT
BACKGROUND: Preterm birth remains the major cause of neonatal death worldwide. South Asia contributes disproportionately to deaths among preterm births worldwide, yet few population-based studies have assessed the underlying causes of deaths. Novel evaluations, including histological and bacteriological assessments of placental and fetal tissues, facilitate more precise determination of the underlying causes of preterm deaths. We sought to assess underlying and contributing causes of preterm neonatal deaths in India and Pakistan. METHODS: The project to understand and research preterm pregnancy outcomes and stillbirths in South Asia (PURPOSe) was a prospective cohort study done in three hospitals in Davangere, India, and two hospitals in Karachi, Pakistan. All pregnant females older than 14 years were screened at the time of presentation for delivery, and those with an expected or known preterm birth, defined as less than 37 weeks of gestation, were enrolled. Liveborn neonates with a weight of 1000 g or more who died by 28 days after birth were included in analyses. Placentas were collected and histologically evaluated. In addition, among all neonatal deaths, with consent, minimally invasive tissue sampling was performed for histological analyses. PCR testing was performed to assess microbial pathogens in the placental, blood, and fetal tissues collected. An independent panel reviewed available data, including clinical description of the case and all clinical maternal, fetal, and placental findings, and results of PCR bacteriological investigation and minimally invasive tissue sampling histology, from all eligible preterm neonates to determine the primary and contributing maternal, placental, and neonatal causes of death. FINDINGS: Between July 1, 2018, and March 26, 2020, of the 3470 preterm neonates enrolled, 804 (23%) died by 28 days after birth, and, of those, 615 were eligible and had their cases reviewed by the panel. Primary maternal causes of neonatal death were hypertensive disease (204 [33%] of 615 cases), followed by maternal complication of pregnancy (76 [12%]) and preterm labour (76 [11%]), whereas the primary placental causes were maternal and fetal vascular malperfusion (172 [28%] of 615) and chorioamnionitis, funisitis, or both (149 [26%]). The primary neonatal cause of death was intrauterine hypoxia (212 [34%] of 615) followed by congenital infections (126 [20%]), neonatal infections (122 [20%]), and respiratory distress syndrome (126 [20%]). INTERPRETATION: In south Asia, intrauterine hypoxia and congenital infections were the major causes of neonatal death among preterm babies. Maternal hypertensive disorders and placental disorders, especially maternal and fetal vascular malperfusion and placental abruption, substantially contributed to these deaths. FUNDING: Bill & Melinda Gates Foundation.
Subject(s)
Communicable Diseases , Perinatal Death , Premature Birth , Communicable Diseases/complications , Female , Humans , Hypoxia/complications , Hypoxia/pathology , Infant, Newborn , Pakistan/epidemiology , Perinatal Death/etiology , Placenta/pathology , Pregnancy , Premature Birth/epidemiology , Prospective StudiesABSTRACT
BACKGROUND: South Asia contributes more than a third of all global stillbirths, yet the causes remain largely unstudied in this region. New investigations, including novel assessments of placental and fetal tissues, facilitate more precise determination of the underlying causes of stillbirth. We sought to assess underlying and contributing causes of stillbirth from settings in India and Pakistan. METHODS: In this prospective cohort study (PURPOSe), we report the cause of death in stillbirths in hospitals in central India and south Pakistan (Davangere, India [three public and private hospitals] and Karachi, Pakistan [one public maternity and one children's hospital]). Women aged 15 years or older and with a known stillbirth (defined as a pregnancy at 20 or more weeks of gestation with the in-utero death of a fetus) weighing 1000 g or more were included in the study. Maternal clinical factors, placental evaluation, fetal tissue evaluation (from minimally invasive tissue sampling), and PCR for microbial pathogens were used to identify the causes of death. An expert panel reviewed available data for all stillbirths to identify the primary and contributing maternal, placental, and fetal causes of stillbirth. FINDINGS: Between Sept 1, 2018, and Feb 12, 2020, 981 stillborns were included and, of those, 611 were reviewed by the expert panel. The primary maternal causes of stillbirth were hypertensive disease in 221 (36%) of 611 stillbirths, followed by severe anaemia in 66 (11%) stillbirths. The primary placental causes were maternal and fetal vascular malperfusion, in 289 (47%) stillbirths. The primary fetal cause of stillbirth was intrauterine hypoxia, in 437 (72%) stillbirths. We assessed the overlap of main causes and 116 (19%) stillbirths had intrauterine hypoxia, placental malperfusion, and eclampsia or pre-eclampsia indicated as primary causes of death. Infection (including of the placenta, its membranes, and in the fetus) and congenital anomalies also were causative of stillbirth. INTERPRETATION: In south Asia, fetal asphyxia is the major cause of stillbirth. Several placental lesions, especially those associated with maternal and fetal vascular malperfusion and placental abruption, have an important role in asphyxia and fetal death. Maternal hypertension, and especially pre-eclampsia, is often the primary maternal condition associated with this pathway. FUNDING: Bill & Melinda Gates Foundation.
Subject(s)
Pre-Eclampsia , Stillbirth , Asphyxia/pathology , Child , Female , Humans , Hypoxia/pathology , India/epidemiology , Pakistan/epidemiology , Placenta/abnormalities , Placenta/blood supply , Placenta/pathology , Pregnancy , Prospective Studies , Stillbirth/epidemiologyABSTRACT
OBJECTIVE: To assess respiratory distress syndrome (RDS) compared with birth asphyxia as the cause of death in preterm newborns, assigned by the neonatal intensive care unit (NICU) physician at the time of death and assigned by a panel with complete obstetric history, placental evaluation, tissue histology and microbiology. DESIGN: Prospective, observational study. SETTINGS: Study NICUs in India and Pakistan. POPULATION: Preterm infants delivered in study facility. METHODS: A total of 410 preterm infants who died in the NICU with cause of death ascertained by the NICU physicians and independently by expert panels. We compared the percentage of cases assigned RDS versus birth asphyxia as cause of death by the physician and the panel. MAIN OUTCOME MEASURES: RDS and birth asphyxia. RESULTS: Of 410 preterm neonatal deaths, the discharging NICU physicians found RDS as a cause of death among 83.2% of the cases, compared with the panel finding RDS in only 51.0%. In the same neonatal deaths, the NICU physicians found birth asphyxia as a cause of death in 14.9% of the deaths, whereas the panels found birth asphyxia in 57.6% of the deaths. The difference was greater in Pakistan were the physicians attributed 89.7% of the deaths to RDS and less than 1% to birth asphyxia whereas the panel attributed 35.6% of the deaths to RDS and 62.7% to birth asphyxia. CONCLUSIONS: NICU physicians who reported cause of death in deceased preterm infants less often attributed the death to birth asphyxia, and instead more often chose RDS, whereas expert panels with more extensive data attributed a greater proportion of deaths to birth asphyxia than did the physicians.
Subject(s)
Asphyxia Neonatorum , Perinatal Death , Respiratory Distress Syndrome, Newborn , Asphyxia , Asphyxia Neonatorum/complications , Developing Countries , Female , Humans , Infant , Infant Mortality , Infant, Newborn , Infant, Premature , Placenta , Pregnancy , Prospective StudiesABSTRACT
Introduction: Maternal infections likely are an important cause of stillbirths, especially in sub-Saharan Africa and south Asia, where the burden is highest. Due to the lack of routine testing for infection, which can be complex and often expensive, the prevalence of infection during pregnancy and the association of many infections with stillbirth are not well-documented, especially in low-resource countries.Methods: Following an extensive literature review of infection and stillbirth initially published in 2010, we conducted a review of literature in the last 10 years to identify infections associated with stillbirth, focused on those in low-resource settings.Results: During the last 10 years, over 40 bacterial, viral and other pathogens have been associated with stillbirth. Newly emerging viral infections such as Denge as well as several well-established, but not yet eliminated infections such as rubella have been associated with stillbirth. Two of the maternal infections most strongly associated with stillbirth, each with about a 2-fold risk, are malaria and syphilis but others have been associated with risk in a range of studies. With a lack of routine antenatal screening, many pathogens are identified as associated with stillbirth only through case reports. Infection remains an important, yet understudied, cause of stillbirth.Conclusion: Research studies to determine definitive associations between various infections and stillbirth are important to better understand the role of infections and strategies to reduce infection-related stillbirth.Summary This review explores the association between infections and stillbirths focusing on low-income country studies published in the last 10 years. Much information about these relationships comes from case reports. Research resulting in a better understanding of the causes and strategies to reduce infection-related stillbirth is necessary.
Subject(s)
Malaria , Syphilis , Africa South of the Sahara/epidemiology , Female , Humans , Pregnancy , Stillbirth/epidemiologyABSTRACT
BACKGROUND: Complete diagnostic autopsy (CDA) is considered to be the gold-standard procedure that aids in determination of cause of death in stillbirths and neonatal deaths. However, CDA is not routinely practiced in South Asian countries due to religious beliefs, lack of expertise, and lack of resources. Minimally invasive tissue sampling (MITS) has been recommended as a less mutilating and less expensive alternative to CDA for obtaining tissues for analysis. The present study aims to evaluate the yield of lung tissue and histological findings using MITS as part of a cause of death analysis for stillborns and preterm neonatal deaths. METHODS: Data were collected during an observational multicenter prospective study called the Project to Understand and Research Preterm birth and Stillbirth (PURPOSe) conducted in India and Pakistan. After obtaining written informed consent from parents, the eligible stillbirths and neonatal deaths were subjected to MITS using a standard protocol. The tissues were obtained from both lungs for histological and microbiological analysis. RESULTS: At both sites, a total of 453 stillbirths and 352 neonatal deaths underwent MITS. For stillbirths and neonatal deaths, the yield of lung tissue using MITS was high (92%). Intrauterine fetal distress and respiratory distress syndrome were the leading lung pathologies reported in stillbirths and neonatal deaths, respectively. CONCLUSIONS: MITS appears to be a reasonable alternative to CDA in obtaining and evaluating lung tissue to inform accurate cause of death analysis in stillbirth and preterm deaths.
Subject(s)
Perinatal Death , Premature Birth , Cause of Death , Female , Humans , Infant, Newborn , Lung , Pregnancy , Prospective Studies , StillbirthABSTRACT
BACKGROUND: Review of data from multiple sources is often necessary to determine cause of death for stillbirths and neonatal deaths, especially in low- to middle-income countries (LMICs) where available data may vary. The minimally invasive tissue sampling (MITS) procedure provides granular histologic and microbiologic data that clinical reports and verbal autopsies cannot provide. Expert panel evaluation of data from individual deaths can be resource-intensive but remains essential to accurately infer causes of death. METHODS: The Project to Understand and Research Preterms and Stillbirths in South Asia (PURPOSe) study uses review panels to evaluate causes of death in 2 LMICs. To make the process manageable, a subset of the study variables was selected with professional input and organized into case reports. Case reports include clinical information, laboratory results, fetal or neonatal organ histology and polymerase chain reaction results from tissue obtained by MITS. Panelists evaluated the complete case report forms and then determined the cause of death based on available data. RESULTS: Computerized case reports averaged 2 to 3 pages. Approximately 6 to 8 cases were reviewed and discussed per 1-hour panel meeting. All panelists were provided the same information; missing data were noted. This limited bias between panelists and across meetings. Study teams notably took ownership of data quality. CONCLUSIONS: Standardized case reports for cause-of-death determination panel evaluation improve the efficiency of the review process, clarify available information, and limit bias across panelists, time, and location.
Subject(s)
Perinatal Death , Stillbirth , Autopsy/methods , Cause of Death , Female , Humans , Infant, Newborn , Pregnancy , Prenatal Care , Stillbirth/epidemiologyABSTRACT
Postmortem studies are crucial for providing insight into emergent diseases. However, a complete autopsy is frequently not feasible in highly transmissible diseases due to biohazard challenges. Minimally invasive autopsy (MIA) is a needle-based approach aimed at collecting samples of key organs without opening the body, which may be a valid alternative in these cases. We aimed to: (a) provide biosafety guidelines for conducting MIAs in COVID-19 cases, (b) compare the performance of MIA versus complete autopsy, and (c) evaluate the safety of the procedure. Between October and December 2020, MIAs were conducted in six deceased patients with PCR-confirmed COVID-19, in a basic autopsy room, with reinforced personal protective equipment. Samples from the lungs and key organs were successfully obtained in all cases. A complete autopsy was performed on the same body immediately after the MIA. The diagnoses of the MIA matched those of the complete autopsy. In four patients, COVID-19 was the main cause of death, being responsible for the different stages of diffuse alveolar damage. No COVID-19 infection was detected in the personnel performing the MIAs or complete autopsies. In conclusion, MIA might be a feasible, adequate and safe alternative for cause of death investigation in COVID-19 cases.
ABSTRACT
Hand hygiene interventions are critical for reducing farmworker hand contamination and preventing the spread of produce-associated illness. Hand hygiene effectiveness may be produce-commodity specific, which could influence implementation strategies. This study's goal was to determine if produce commodity influences the ability of handwashing with soap and water or two-step alcohol-based hand sanitizer (ABHS) interventions to reduce soil and bacteria on farmworker hands. Farmworkers (n = 326) harvested produce (cantaloupe, jalapeño, and tomato) for 30 to 90 minutes before engaging in handwashing, two-step ABHS (jalapeño and cantaloupe), or no hand hygiene. Hands were rinsed to measure amounts of soil (absorbance at 600 nm) and indicator bacteria (coliforms, Enterococcus sp., generic Escherichia coli, and Bacteroidales universal [AllBac] and human-specific [BFD] 16S rRNA gene markers). Without hand hygiene, bacterial concentrations (0.88 to 5.1 log10 CFU/hand) on hands significantly differed by the produce commodity harvested. Moderate significant correlations (ρ = -0.41 to 0.56) between soil load and bacterial concentrations were observed. There were significant produce-commodity-specific differences in the ability of handwashing and two-step ABHS interventions to reduce soil (P < 0.0001), coliforms (P = 0.002), and Enterococcus sp. (P = 0.003), but not the Bacteroidales markers AllBac (P = 0.4) or BFD (P = 0.3). Contamination on hands of farmworkers who harvested cantaloupe was more difficult to remove. Overall, we found that a two-step ABHS intervention was similar to handwashing with soap and water at reducing bacteria on farmworker hands. In summary, produce commodity type should be considered when developing hand hygiene interventions on farms.IMPORTANCE This study demonstrated that the type of produce commodity handled influences the ability of handwashing with soap and water or a two-step alcohol-based hand sanitizer (ABHS) intervention to reduce soil and bacterial hand contamination. Handwashing with soap and water, as recommended by the FDA's Produce Safety Rule, when tested in three agricultural environments, does not always reduce bacterial loads. Consistent with past results, we found that the two-step ABHS method performed similarly to handwashing with soap and water but also does not always reduce bacterial loads in these contexts. Given the ease of use of the two-step ABHS method, which may increase compliance, the two-step ABHS method should be further evaluated and possibly considered for implementation in the agricultural environment. Taken together, these results provide important information on hand hygiene effectiveness in three agricultural contexts.
Subject(s)
Bacterial Load/drug effects , Crop Production , Crops, Agricultural/classification , Hand Disinfection/instrumentation , Hand Sanitizers/administration & dosage , Hand/microbiology , Soil , Capsicum/growth & development , Cucumis melo/growth & development , Ethanol/chemistry , Farmers , Hand Sanitizers/chemistry , Humans , Solanum lycopersicum/growth & development , MexicoABSTRACT
BACKGROUND: Drinking water is a lingering hazard in the effort to eliminate childhood exposure to lead (Pb), a neurotoxin that affects cognitive and behavioral development. This study characterized Pb in municipal drinking water at North Carolina, US, childcare centers. The study also demonstrates a scalable, citizen science-based drinking water testing strategy for Pb at childcare centers. METHODS: Licensed childcare centers in four North Carolina counties were recruited. One administrator per center completed a survey and was trained to collect first-draw drinking water samples in their center. Samples were shipped with pre-paid labels for laboratory analysis using inductively coupled plasma mass spectrometry. Multilevel logistic regression and Bayesian network analysis were used to identify factors associated with a risk of exceeding the 1 µg/L American Academy of Pediatrics reference level and the US Environmental Protection Agency (US EPA) 15 µg/L treatment-based action level. Results were provided to centers along with risk mitigation recommendations. RESULTS: Of 103 enrolled centers, 86 completed the study, submitting 1,266 drinking water samples in total. Approximately 77% of drinking water samples contained detectable Pb (≥0.1 µg/L), and 97% of centers had at least one drinking water sample with detectable Pb. More than 63% of centers had at least one drinking water sample with >1 µg/L Pb, and 17% of centers had at least one drinking water sample with Pb above 15 µg/L. There was high variability in Pb concentrations at water points within the same center. DISCUSSION: This study demonstrated a high prevalence and variability of Pb in first-draw samples of drinking water at childcare centers in North Carolina, US. Results underscore the importance of testing for Pb at every tap used for drinking and cooking in childcare centers. The use of employees as citizen scientists is a feasible strategy to identify Pb in specific drinking water taps.
Subject(s)
Drinking Water , Lead , Water Pollutants, Chemical , Bayes Theorem , Child , Citizen Science , Drinking Water/chemistry , Humans , Lead/analysis , North CarolinaABSTRACT
Globally, vitamin A deficiency (VAD) affects nearly 200 million children with negative health consequences. VAD can be measured by a retinol-binding protein (RBP) and serum retinol concentrations. Their concentrations are not always present in a 1:1 molar ratio and are affected by inflammation. This study sought to quantify VAD and its impact on infant mortality and infectious morbidity during the first 18 months of life in a cohort of mother-infant dyads in El Alto, Bolivia, while accounting for the previously mentioned measurement issues. Healthy mother-infant dyads (n = 461) were enrolled from two hospitals and followed for 12 to 18 months. Three serum samples were collected (at one to two, six to eight, and 12 to 18 months of infant age) and analyzed for RBP, and a random 10% subsample was analyzed for retinol. Linear regression of RBP on retinol was used to generate RBP cut-offs equivalent to retinol <0.7 µmol/L. All measures of RBP and retinol were adjusted for inflammation, which was measured by a C-reactive protein and alpha (1)-acid glycoprotein serum concentrations using linear regression. Infant mortality and morbidity rates were calculated and compared by early VAD status at two months of age. Retinol and RBP were weakly affected by inflammation. This association varied with infant age. Estimated VAD (RBP < 0.7 µmol/L) decreased from 71.0% to 14.8% to 7.7% at two, six to eight, and 12 to 18 months of age. VAD was almost nonexistent in mothers. Early VAD was not significantly associated with infant mortality or morbidity rates. This study confirmed a relationship between inflammation and vitamin A biomarkers for some subsets of the population and suggested that the vitamin A status in early infancy improves with age and may not have significantly affected morbidity in this population of healthy infants.
Subject(s)
C-Reactive Protein/metabolism , Inflammation/blood , Nutritional Status , Orosomucoid/metabolism , Retinol-Binding Proteins/metabolism , Vitamin A Deficiency/blood , Vitamin A/blood , Age Factors , Biomarkers/blood , Bolivia , Cohort Studies , Humans , Infant , Inflammation/complications , Morbidity , Vitamin A Deficiency/complicationsABSTRACT
Lead was a known toxin before the Roman Empire, yet exposure remains a public health concern today. Although there is no safe lead exposure level, a health-based drinking water standard has not been established. The Clean Water for Carolina Kids Study highlights the need for a health-based standard.
Subject(s)
Child Health , Drinking Water/chemistry , Lead/analysis , Water Pollution, Chemical/analysis , Water Pollution, Chemical/prevention & control , Child , Communication , Humans , Water Pollution, Chemical/adverse effectsABSTRACT
BACKGROUND: In South Asia, where most stillbirths and neonatal deaths occur, much remains unknown about the causes of these deaths. About one-third of neonatal deaths are attributed to prematurity, yet the specific conditions which cause these deaths are often unclear as is the etiology of stillbirths. In low-resource settings, most women are not routinely tested for infections and autopsy is rare. METHODS: This prospective, cohort study will be conducted in hospitals in Davengere, India and Karachi, Pakistan. All women who deliver either a stillbirth or a preterm birth at one of the hospitals will be eligible for enrollment. With consent, the participant and, when applicable, her offspring, will be followed to 28-days post-delivery. A series of research tests will be conducted to determine infection and presence of other conditions which may contribute to the death. In addition, all routine clinical investigations will be documented. For both stillbirths and preterm neonates who die ≤ 28 days, with consent, a standard autopsy as well as minimally invasive tissue sampling will be conducted. Finally, an expert panel will review all available data for stillbirths and neonatal deaths to determine the primary and contributing causes of death using pre-specified guidance. CONCLUSION: This will be among the first studies to prospectively obtain detailed information on causes of stillbirth and preterm neonatal death in low-resource settings in Asia. Determining the primary causes of death will be important to inform strategies most likely to reduce the high mortality rates in South Asia. TRIAL REGISTRATION: Clinicaltrials.gov ( NCT03438110 ) Clinical Trial Registry of India ( CTRI/2018/03/012281 ).
Subject(s)
Infant Mortality , Infant, Premature , Pregnancy Outcome , Stillbirth , Adolescent , Cohort Studies , Female , Humans , Infant , Infant, Newborn , Perinatal Death/etiology , Pregnancy , Premature Birth/mortality , Prospective StudiesABSTRACT
BACKGROUND: Iron deficiency (ID) is the most common micronutrient deficiency worldwide, with potentially severe consequences on child neurodevelopment. Though exclusive breastfeeding (EBF) is recommended for 6 months, breast milk has low iron content. This study aimed to estimate the effect of the length of EBF on iron status at 6 - 8 months of age among a cohort of Bolivian infants. METHODS: Mother-infant pairs were recruited from 2 hospitals in El Alto, Bolivia, and followed from one through 6 - 8 months of age. Singleton infants > 34 weeks gestational age, iron-sufficient at baseline, and completing blood draws at 2 and 6 - 8 months of age were eligible for inclusion (N = 270). Ferritin was corrected for the effect of inflammation. ID was defined as inflammation-corrected ferritin < 12 µg/L, and anemia was defined as altitude-corrected hemoglobin < 11 g/dL; IDA was defined as ID plus anemia. The effect of length of EBF (infant received only breast milk with no other liquids or solids, categorized as < 4, 4 - 6, and > 6 months) was assessed for ID, IDA, and anemia (logistic regression) and ferritin (Fer) and hemoglobin (Hb, linear regression). RESULTS: Low iron status was common among infants at 6 - 8 months: 56% of infants were ID, 76% were anemic, and 46% had IDA. EBF of 4 months and above was significantly associated with ID as compared with EBF < 4 months (4 - 6 months: OR 2.0 [1.1 - 3.4]; > 6 months: 3.3 [1.0 - 12.3]), but not with IDA (4 - 6 months: OR 1.4 [0.8 - 2.4]; > 6 months: 2.2 [0.7 - 7.4]), or anemia (4 - 6 months: OR 1.4 [0.7 - 2.5]; > 6 months: 1.5 [0.7 - 7.2]). Fer and Hb concentrations were significantly lower with increasing months of EBF. CONCLUSIONS: Results suggest a relationship between prolonged EBF and ID, but are not sufficient to support changes to current breastfeeding recommendations. More research is needed in diverse populations, including exploration of early interventions to address infant IDA.
Subject(s)
Anemia, Iron-Deficiency/etiology , Breast Feeding/adverse effects , Anemia, Iron-Deficiency/diagnosis , Anemia, Iron-Deficiency/epidemiology , Bolivia/epidemiology , Breast Feeding/methods , Developing Countries , Female , Humans , Infant , Linear Models , Longitudinal Studies , Male , Risk Factors , Time FactorsABSTRACT
BACKGROUND: Implementing rigorous epidemiologic studies in low-resource settings involves challenges in participant recruitment and follow-up (e.g., mobile populations, distrust), biological sample collection (e.g., cold-chain, laboratory equipment scarcity) and data collection (e.g., literacy, staff training, and infrastructure). This article describes the use of a monitoring and evaluation (M&E) framework to improve study efficiency and quality during participant engagement, and biological sample and data collection in a longitudinal cohort study of Bolivian infants. METHODS: The study occurred between 2013 and 2015 in El Alto, Bolivia, a high-altitude, urban, low-resource community. The study's M&E framework included indicators for participant engagement (e.g., recruitment, retention, safety), biological sample (e.g., stool and blood), and data (e.g., anthropometry, questionnaires) collection and quality. Monitoring indicators were measured regularly throughout the study and used for course correction, communication, and staff retraining. RESULTS: Participant engagement indicators suggested that enrollment objectives were met (461 infants), but 15% loss-to-follow-up resulted in only 364 infants completing the study. Over the course of the study, there were four study-related adverse events (minor swelling and bruising related to a blood draw) and five severe adverse events (infant deaths) not related to study participation. Biological sample indicators demonstrated two blood samples collected from 95% (333 of 350 required) infants and stool collected for 61% of reported infant diarrhea episodes. Anthropometry data quality indicators were extremely high (median SDs for weight-for-length, length-for-age and weight-for-age z-scores 1.01, 0.98, and 1.03, respectively), likely due to extensive training, standardization, and monitoring efforts. CONCLUSIONS: Conducting human subjects research studies in low-resource settings often presents unique logistical difficulties, and collecting high-quality data is often a challenge. Investing in comprehensive M&E is important to improve participant recruitment, retention and safety, and sample and data quality. The M&E framework from this study can be applied to other longitudinal studies.
Subject(s)
Population Surveillance , Program Evaluation , Rotavirus Infections/prevention & control , Rotavirus Vaccines/administration & dosage , Bolivia/epidemiology , Diarrhea, Infantile/epidemiology , Female , Humans , Infant , Infant Nutritional Physiological Phenomena , Inflammation/epidemiology , Male , Prospective Studies , Research Design/standardsABSTRACT
Wildlife intrusion has been associated with pathogen contamination of produce. However, few studies have examined pathogen transfer from wildlife feces to pre-harvest produce. This study was performed to calculate transfer coefficients for Escherichia coli from simulated wildlife feces to field-grown lettuce during irrigation. Rabbit feces inoculated with a 3-strain cocktail of non-pathogenic E. coli were placed in a lettuce field 2.5-72 h before irrigation. Following irrigation, the E. coli concentration on the lettuce was determined. After exclusion of an outlier with high E. coli levels (Most Probable Number = 5.94*108), the average percent of E. coli in the feces that transferred to intact lettuce heads was 0.0267% (Standard Error [SE] = 0.0172). Log-linear regression showed that significantly more E. coli transferred to outer leaves compared to inner leaves (Effect = 1.3; 95% Confidence Interval = 0.4, 2.1). Additionally, the percent of E. coli that transferred from the feces to the lettuce decreased significantly with time after fecal placement, and as the distance between the lettuce and the feces, and the lettuce and the sprinklers increased. These findings provide key data that may be used in future quantitative risk assessments to identify potential intervention strategies for reducing food safety risks associated with fresh produce.
Subject(s)
Animals, Wild/microbiology , Escherichia coli/isolation & purification , Feces/microbiology , Food Contamination/analysis , Lactuca/microbiology , Agricultural Irrigation , Animals , Escherichia coli/classification , Escherichia coli/genetics , Food Safety , New EnglandABSTRACT
Although wildlife intrusion and untreated manure have been associated with microbial contamination of produce, relatively few studies have examined the survival of Escherichia coli on produce under field conditions following contamination (e.g., via splash from wildlife feces). This experimental study was performed to estimate the die-off rate of E. coli on preharvest lettuce following contamination with a fecal slurry. During August 2015, field-grown lettuce was inoculated via pipette with a fecal slurry that was spiked with a three-strain cocktail of rifampin-resistant nonpathogenic E. coli. Ten lettuce heads were harvested at each of 13 time points following inoculation (0, 2.5, 5, and 24 h after inoculation and every 24 h thereafter until day 10). The most probable number (MPN) of E. coli on each lettuce head was determined, and die-off rates were estimated. The relationship between sample time and the log MPN of E. coli per head was modeled using a segmented linear model. This model had a breakpoint at 106 h (95% confidence interval = 69, 142 h) after inoculation, with a daily decrease of 0.70 and 0.19 log MPN for 0 to 106 h and 106 to 240 h following inoculation, respectively. These findings are consistent with die-off rates obtained in similar studies that assessed E. coli survival on produce following irrigation. Overall, these findings provide die-off rates for E. coli on lettuce that can be used in future quantitative risk assessments.
Subject(s)
Escherichia coli/growth & development , Food Contamination/analysis , Lactuca/microbiology , Microbial Viability , Colony Count, Microbial , Escherichia coli O157 , Food Microbiology , Humans , New EnglandABSTRACT
To improve food safety on farms, it is critical to quantify the impact of environmental microbial contamination sources on fresh produce. However, studies are hampered by difficulties achieving study designs with powered sample sizes to elucidate relationships between environmental and produce contamination. Our goal was to quantify, in the agricultural production environment, the relationship between microbial contamination on hands, soil, and water and contamination on fresh produce. In 11 farms and packing facilities in northern Mexico, we applied a matched study design: composite samples (n = 636, equivalent to 11,046 units) of produce rinses were matched to water, soil, and worker hand rinses during two growing seasons. Microbial indicators (coliforms, Escherichia coli, Enterococcus spp., and somatic coliphage) were quantified from composite samples. Statistical measures of association and correlations were calculated through Spearman's correlation, linear regression, and logistic regression models. The concentrations of all microbial indicators were positively correlated between produce and hands (ρ range, 0.41 to 0.75; P < 0.01). When E. coli was present on hands, the handled produce was nine times more likely to contain E. coli (P < 0.05). Similarly, when coliphage was present on hands, the handled produce was eight times more likely to contain coliphage (P < 0.05). There were relatively low concentrations of indicators in soil and water samples, and a few sporadic significant associations were observed between contamination of soil and water and contamination of produce. This methodology provides a foundation for future field studies, and results highlight the need for interventions surrounding farmworker hygiene and sanitation to reduce microbial contamination of farmworkers' hands.IMPORTANCE This study of the relationships between microbes on produce and in the farm environment can be used to support the design of targeted interventions to prevent or reduce microbial contamination of fresh produce with associated reductions in foodborne illness.