Ann Ib Postgrad Med. 2021 Dec;19(2):103-111.
INTRODUCTION: Primary Health Care (PHC) workers are usually the frontline health workers involved in disseminating health education to the community and implementing cholera prevention and management guidelines. Given that inadequate health worker performance has been a problem in resource-limited settings such as Nigeria and poor health worker knowledge has been implicated in poor health status in developing nations, continuous training of health workers to improve their knowledge has been recommended to improve health outcomes.
OBJECTIVE: This study seeks to ascertain the level of improvement in the knowledge of health workers on cholera, if any, after one of such interventions was carried out in Oyo State. Similarly, the study seeks to discern the specific domains of knowledge on cholera, if any, which were significantly affected by the intervention.
METHODS: The research was conducted utilizing a pre-post study design to recruit PHC health workers from four local government areas of Oyo State between October and November 2016. Baseline and endline data were collected at both intervention and control sites using a self-administered questionnaire with sections eliciting responses to questions on general knowledge of symptoms of cholera, prevention methods, knowledge and practice of safety procedures health workers. Descriptive statistics and chi-square tests were used to present the data and test for statistical associations between categorical variables at 5% respectively.
RESULTS: A total of 542 health workers divided into 2 groups (intervention and control), were interviewed at baseline and at endline. At baseline, the 40-49 years age group was the most represented in the intervention arm (40.0%), the 30-39 years age group was the most represented in the control arm (34.2%). At baseline, only 35.2% of health workers in the intervention sites had good knowledge on cholera. This figure was increased to 52.7% after the intervention. This difference in proportions was also statistically significant (p=0.004). In the control sites, the opposite was observed as the proportion of health workers with good knowledge on cholera slightly reduced from 47.2% to 43.6%. This difference was however not statistically significant (p=0.563).
CONCLUSION: The results from the evaluation of the intervention show that the training significantly improved the overall knowledge of health workers. However, future training interventions can be aimed at improving knowledge of health workers on alert threshold of cholera. In addition, continuous education programs on disease and surveillance and notification should be planned for PHC workers to improve their knowledge.
Are better existing WASH practices in urban slums associated with a lower long-term risk of severe cholera? A prospective cohort study with 4 years of follow-up in Mirpur, Bangladesh
BMJ Open. 2022 Sep 21;12(9):e060858. doi: 10.1136/bmjopen-2022-060858.
OBJECTIVE: To investigate the association between existing household water quality, sanitation and hygiene (WASH) practices and severe cholera risk in a dense urban slum where cholera is highly endemic.
DESIGN, SETTING AND PARTICIPANTS: We assembled a large prospective cohort within a cluster randomised trial evaluating the effectiveness of oral cholera vaccine. Our dynamic cohort population (n=193 576) comprised individuals living in the 'non-intervention' clusters of the trial, and were followed over 4 years. This study was conducted in a dense urban slum community of Dhaka, Bangladesh and cholera surveillance was undertaken in 12 hospitals serving the study area.
PRIMARY OUTCOME MEASURE: First severe cholera episode detected during follow-up period.
METHODS: We applied a machine learning algorithm on a training subpopulation (n=96 943) to develop a binary ('better', 'not better') composite WASH variable predictive of severe cholera. The WASH rule was evaluated for performance in a separate validation subpopulation (n=96 633). Afterwards, we used Cox regression models to evaluate the association between 'better' WASH households and severe cholera risk over 4 years in the entire study population.
RESULTS: The 'better' WASH rule found that water quality and access were the most significant factors associated with severe cholera risk. Members of 'better' WASH households, constituting one-third of the population, had a 47% reduced risk of severe cholera (95% CI: 29 to 69; p<0.001), after adjusting for covariates. The protective association between living in a 'better' WASH household and severe cholera persisted in all age groups.
CONCLUSIONS: Salutary existing household WASH practices were associated with a significantly reduced long-term risk of severe cholera in an urban slum of Dhaka. These findings suggest that WASH adaptations already practised in the community may be important for developing and implementing effective and sustainable cholera control programmes in similar settings.
TRIAL REGISTRATION NUMBER: This article is a re-analysis of data from a cluster randomized trial; can be found on ClinicalTrials.gov NCT01339845.
Determining factors associated with cholera disease in Ethiopia using Bayesian hierarchical modeling
BMC Public Health. 2022 Sep 20;22(1):1779. doi: 10.1186/s12889-022-14153-1.
BACKGROUND: Cholera is a diarrheal disease caused by infection of the intestine with the gram-negative bacteria Vibrio cholera. It is caused by the ingestion of food or water and infected all age groups. This study aimed at identifying risk factors associated with cholera disease in Ethiopia using the Bayesian hierarchical model.
METHODS: The study was conducted in Ethiopia across regions and this study used secondary data obtained from the Ethiopian public health institute. Latent Gaussian models were used in this study; which is a group of models that contains most statistical models used in practice. The posterior marginal distribution of the Latent Gaussian models with different priors is determined by R-Integrated Nested Laplace Approximation.
RESULTS: There were 2790 cholera patients in Ethiopia across the regions. There were 81.61% of patients are survived from cholera outbreak disease and the rest 18.39% have died. There was 39% variation across the region in Ethiopia. Latent Gaussian models including random and fixed effects with standard priors were the best model to fit the data based on deviance. The odds of surviving from cholera outbreak disease for inpatient status are 0.609 times less than the outpatient status.
CONCLUSIONS: The authors conclude that the fitted latent Gaussian models indicate the predictor variables; admission status, aged between 15 and 44, another sick person in a family, dehydration status, oral rehydration salt, intravenous, and antibiotics were significantly associated with cholera outbreak disease.
Epidemiology, diagnostics and factors associated with mortality during a cholera epidemic in Nigeria, October 2020-October 2021: a retrospective analysis of national surveillance data
BMJ Open. 2022 Sep 19;12(9):e063703. doi: 10.1136/bmjopen-2022-063703.
OBJECTIVES: Nigeria reported an upsurge in cholera cases in October 2020, which then transitioned into a large, disseminated epidemic for most of 2021. This study aimed to describe the epidemiology, diagnostic performance of rapid diagnostic test (RDT) kits and the factors associated with mortality during the epidemic.
DESIGN: A retrospective analysis of national surveillance data.
SETTING: 33 of 37 states (including the Federal Capital Territory) in Nigeria.
PARTICIPANTS: Persons who met cholera case definition (a person of any age with acute watery diarrhoea, with or without vomiting) between October 2020 and October 2021 within the Nigeria Centre for Disease Control surveillance data.
OUTCOME MEASURES: Attack rate (AR; per 100 000 persons), case fatality rate (CFR; %) and accuracy of RDT performance compared with culture using area under the receiver operating characteristic curve (AUROC). Additionally, individual factors associated with cholera deaths and hospitalisation were presented as adjusted OR with 95% CIs.
RESULTS: Overall, 93 598 cholera cases and 3298 deaths (CFR: 3.5%) were reported across 33 of 37 states in Nigeria within the study period. The proportions of cholera cases were higher in men aged 5-14 years and women aged 25-44 years. The overall AR was 46.5 per 100 000 persons. The North-West region recorded the highest AR with 102 per 100 000. Older age, male gender, residency in the North-Central region and severe dehydration significantly increased the odds of cholera deaths. The cholera RDT had excellent diagnostic accuracy (AUROC=0.91; 95% CI 0.87 to 0.96).
CONCLUSIONS: Cholera remains a serious public health threat in Nigeria with a high mortality rate. Thus, we recommend making RDT kits more widely accessible for improved surveillance and prompt case management across the country.
Genetic, Epigenetic, and Molecular Biology of Obesity: From Pathology to Therapeutics the Way Forward
J Assoc Physicians India. 2022 Sep;70(9):11-12. doi: 10.5005/japi-11001-0080.
Obesity is a globally expanding silent epidemic having multiple risk factors and consequences associated with it. Genetic factors have been found to be playing undeniable roles in obesity. Intermingled relationship between epigenetics, metagenomics, and the environment influences obesity traits. High precision diagnostic tools have outlined many single nucleotide polymorphisms (SNPs), as well as many novel genes, that have been identified that create an obesogenic environment. Rare single-gene diseases can lead to early childhood obesity and less satiety. With almost 30% of the global population being under the grip of obesity, the coming days are alarming. This review summarizes the existing knowledge on the genetic causes of obesity including the epidemiology as well as the issues of concern and new additions to the list. Furthermore, we discuss the ways to enhance the healthcare outcome for patients of obesity through interdepartmental collaborations apart from pharmacological therapy that is still limited to a few drugs. The teamwork of geneticists, genetic counselors, physicians, bariatric surgeons, nurses, endocrinologists, and pharmacists may provide promising results in intervention.
An Assessment of Household Knowledge and Practices during a Cholera Epidemic-Dar es Salaam, Tanzania, 2016
Am J Trop Med Hyg. 2022 Sep 6:tpmd210597. doi: 10.4269/ajtmh.21-0597. Online ahead of print.
From August 15, 2015 to March 5, 2016, Tanzania reported 16,521 cholera cases and 251 deaths, with 4,596 cases and 44 deaths in its largest city, Dar es Salaam. To evaluate outbreak response efforts, we conducted a household survey with drinking water testing in the five most affected wards in Dar es Salaam. We interviewed 641 households 6 months after the beginning of the outbreak. Although most respondents knew that cholera causes diarrhea (90%) and would seek care if suspecting cholera (95%), only 45% were aware of the current outbreak in the area and only 5% would use oral rehydration salts (ORS) if ill. Of 200 (31%) respondents reporting no regular water treatment, 46% believed treatment was unnecessary and 18% believed treatment was too expensive. Fecal contamination was found in 45% of water samples and was associated with water availability (P = 0.047). Only 11% of samples had detectable free chlorine residual, which was associated with water availability (P = 0.025), reported current water treatment (P = 0.006), and observed free chlorine product in the household (P = 0.015). The provision of accessible, adequately chlorinated water supply, and implementation of social mobilization campaigns advocating household water treatment and use of ORS should be prioritized to address gaps in cholera prevention and treatment activities.
World J Diabetes. 2022 Jul 15;13(7):584-586. doi: 10.4239/wjd.v13.i7.584.
Spatial epidemiology is the description and analysis of geographic patterns and variations in disease risk factors, morbidity and mortality with respect to their distributions associated with demographic, socioeconomic, environmental, health behavior, and genetic risk factors, and time-varying changes. In the Letter to Editor, we had a brief description of the practice for the mortality and the space-time patterns of John Snow's map of cholera epidemic in London, United Kingdom in 1854. This map is one of the earliest public heath practices of developing and applying spatial epidemiology. In the early history, spatial epidemiology was predominantly applied in infectious disease and risk factor studies. However, since the recent decades, noncommunicable diseases have become the leading cause of death in both developing and developed countries, spatial epidemiology has been used in the study of noncommunicable disease. In the Letter, we addressed two examples that applied spatial epidemiology to cluster and identify stroke belt and diabetes belt across the states and counties in the United States. Similar to any other epidemiological study design and analysis approaches, spatial epidemiology has its limitations. We should keep in mind when applying spatial epidemiology in research and in public health practice.
PLoS Genet. 2022 Aug 26;18(8):e1010250. doi: 10.1371/journal.pgen.1010250. eCollection 2022 Aug.
The current circulating pandemic El Tor biotype of Vibrio cholerae has persisted for over sixty years and is characterized by its acquisition of two unique genomic islands called the Vibrio Seventh Pandemic Islands 1 and 2 (VSP-I and VSP-II). However, the functions of most of the genes on VSP-I and VSP-II are unknown and the advantages realized by El Tor through these two islands are not clear. Recent studies have broadly implicated these two mobile genetic elements with phage defense. Still, protection against phage infection through these islands has not been observed directly in any V. cholerae El Tor biotype. Here we report the isolation of a circulating phage from a cholera patient stool sample and demonstrate that propagation of this phage in its native host is inhibited by elements in both VSP-I and VSP-II, providing direct evidence for the role of these genomic islands in phage defense. Moreover, we show that these defense systems are regulated by quorum sensing and active only at certain cell densities. Finally, we have isolated a naturally occurring phage variant that is resistant to the defense conferred by the VSP islands, illustrating the countermeasures used by phages to evade these defense mechanisms. Together, this work demonstrates a functional role for the VSPs in V. cholerae and highlights the key regulatory and mechanistic insights that can be gained by studying anti-phage systems in their native contexts.
Exploring Japanese Kampo medicine in fighting epidemics: discovering and popularising croton and satou as 'specific drugs' to treat cholera
Zhonghua Yi Shi Za Zhi. 2022 Jul 28;52(4):206-212. doi: 10.3760/cma.j.cn112155-20220617-00087.
Japanese Kampo medicine (medicine with Han Fang) was found effective to treat some epidemic diseases.Historical records show that Namikawa Saimin, a Kampo medicine (Han Fang Medicine) practitioner during the cholera pandemic in the period of Ansei in Japan (1858-1860), discovered that the treatment effect of croton fruit against cholera was remarkable. Another physician in Naniwa also found that satou (Zhǎ Dá, visceral stones of animals and livestock) had the same effect in treating cholera. Subsequently, Wani Tadatane, an official physician in Komatsu Han of Iyo Province, learned about Namikawa Saimin and the use of croton fruit, and a medical officer in Kohofu, Masugi Fuminori, also heard of the story of the physician from Naniwa. Wani Tadatane and Masugi Fuminori verified the effect of croton fruit and satou on cholera treatment respectively. They regarded these two medical materials as the 'specific drugs' for cholera treatment by drawing on the interpretation and understanding of traditional Chinese medicine in terms of the efficacy of these two drugs. In this sense, croton fruit as a 'specific drug' for cholera treatment was widely accepted in the Kampo medical field (Han medicine area in Japan). The development of the use of satou by Masugi Fuminori could not be traced back because of the lack of historical records.
Heterogeneous Growth Enhancement of Vibrio cholerae in the Presence of Different Phytoplankton Species
Appl Environ Microbiol. 2022 Sep 13;88(17):e0115822. doi: 10.1128/aem.01158-22. Epub 2022 Aug 24.
Vibrio cholerae is a ubiquitously distributed human pathogen that naturally inhabits marine and estuarine ecosystems. Two serogroups are responsible for causing cholera epidemics, O1 and O139, but several non-O1 and non-O139 V. cholerae (NOVC) strains can induce cholera-like infections. Outbreaks of V. cholerae have previously been correlated with phytoplankton blooms; however, links to specific phytoplankton species have not been resolved. Here, the growth of a NOVC strain (S24) was measured in the presence of different phytoplankton species, alongside phytoplankton abundance and concentrations of dissolved organic carbon (DOC). During 14-day experiments, V. cholerae S24 was cocultured with strains of the axenic phytoplankton species Actinocyclus curvatulus, Cylindrotheca closterium, a Pseudoscourfieldia sp., and a Picochlorum sp. V. cholerae abundances significantly increased in the presence of A. curvatulus, C. closterium, and the Pseudoscourfieldia sp., whereas abundances significantly decreased in the Picochlorum sp. coculture. V. cholerae growth was significantly enhanced throughout the cogrowth experiment with A. curvatulus, whereas when grown with C. closterium and the Pseudoscourfieldia sp., growth only occurred during the late stationary phase of the phytoplankton growth cycle, potentially coinciding with a release of DOC from senescent phytoplankton cells. In each of these cases, significant correlations between phytoplankton-derived DOC and V. cholerae cell abundances occurred. Notably, the presence of V. cholerae also promoted the growth of A. curvatulus and Picochlorum spp., highlighting potential ecological interactions. Variations in abundances of NOVC identified here highlight the potential diversity in V. cholerae-phytoplankton ecological interactions, which may inform efforts to predict outbreaks of NOVC in coastal environments. IMPORTANCE Many environmental strains of V. cholerae do not cause cholera epidemics but remain a public health concern due to their roles in milder gastrointestinal illnesses. With emerging evidence that these infections are increasing due to climate change, determining the ecological drivers that enable outbreaks of V. cholerae in coastal environments is becoming critical. Links have been established between V. cholerae abundance and chlorophyll a levels, but the ecological relationships between V. cholerae and specific phytoplankton species are unclear. Our research demonstrated that an environmental strain of V. cholerae (serogroup 24) displays highly heterogenous interactions in the presence of different phytoplankton species with a relationship to the dissolved organic carbon released by the phytoplankton species. This research points toward the complexity of the interactions of environmental strains of V. cholerae with phytoplankton communities, which we argue should be considered in predicting outbreaks of this pathogen.
Altered Molecular Attributes and Antimicrobial Resistance Patterns of Vibrio cholerae O1 El Tor Strains Isolated from the Cholera Endemic Regions of India
J Appl Microbiol. 2022 Aug 24. doi: 10.1111/jam.15794. Online ahead of print.
AIMS: The present study aimed to document the comparative analysis of differential hyper-virulent features of Vibrio cholerae O1 strains isolated during 2018 from cholera endemic regions in Gujarat and Maharashtra (Western India) and West Bengal (Eastern India).
METHODS AND RESULTS: A total of 87 V. cholerae O1 clinical strains from Western India and 48 from Eastern India were analyzed for a number of biotypic and genotypic features followed by antimicrobial resistance (AMR) profile. A novel PCR was designed to detect a large fragment deletion in the Vibrio seventh pandemic island II (VSP-II) genomic region, which is a significant genetic feature of the V. cholerae strains that has caused Yemen cholera outbreak. All the strains from Western India were belong to the Ogawa serotype, polymyxin B-sensitive, hemolytic, had a deletion in VSP-II (VSP-IIC) region and carried Haitian genetic alleles of ctxB, tcpA and rtxA. Conversely, 14.6% (7/48) of the strains from Eastern India belonged to the Inaba serotype, polymyxin B-resistant, non-hemolytic, harbored VSP-II other than VSP-IIC type, classical ctxB, Haitian tcpA and El Tor rtxA alleles. Resistance to tetracycline and chloramphenicol has been observed in strains from both the regions.
CONCLUSIONS: This study showed hyper-virulent, polymyxin B-sensitive epidemic causing strains in India along with the strains with polymyxin B-resistant and non-hemolytic traits that may spread and cause serious disease outcome in future.
SIGNIFICANCE AND IMPACT OF THE STUDY: The outcomes of this study can help to improve the understanding of the hyper-pathogenic property of recently circulating pandemic V. cholerae strains in India. A special attention is also needed on the monitoring of AMR surveillance because V. cholerae strains are losing susceptibility to many antibiotics used as a second line of defense in the treatment of cholera.
Effectiveness and quality of risk communication process in Ethiopia: The case of risk communication during cholera outbreak in Addis Ababa, Ethiopia
PLoS One. 2022 Aug 19;17(8):e0265203. doi: 10.1371/journal.pone.0265203. eCollection 2022.
BACKGROUND: WHO states risk communication as the conversation of actual information, guidance, and thoughts between specialists and people fronting risks to their well-being, economic or social safety. As risk communication activities are complex and costly usually, evaluation assessment are the best approach to advance risk communication interventions. This study aims to evaluate the effectiveness of risk communication and the quality of health communication materials developed during the 2019 cholera outbreak at Addis Ababa, Ethiopia.
METHODS: A community-based parallel mixed design was conducted from May to June 2020 at Addis Ababa. A total of 605 adults were selected randomly from Addis Ketema sub-city and ten purposely selected adults were interviewed for qualitative data. In addition eight health communication materials on cholera were randomly selected for evaluation. The quantitative data were analyzed using SPSS version 25. After audio recorded interviews transcribed verbatim and translated into English the qualitative data were entered into open code version 4.02 for analysis. And then the data were analyzed using thematic analysis.
RESULT: Respondents exposed for cholera related messages and outbreak information were 71.8% and 52.7% respectively. Respondents have moderate knowledge for cholera with (M = 14.72 and SD ±4.02) with (0-34) scale range. Both Television and radio spots were found as simple and easy to understand and printed health communication materials score low quality. Poor documentation, lack of data management system and less attention for risk communication activities were identified as a gaps in risk communication in the study settings.
CONCLUSION: this study revealed the positive effects of risk communication messages in increasing individuals' knowledge. Even though the risk communication spots were found to be simple and easy to understand, the quality of printed materials was low and less attention was given for the risk-communication activities. Thus, strengthening the quality of risk communication and materials development process is very important to bring desired effects in disease prevention strategies and for effective emergency responses in the future.
Examining the Relationship between Climate Change and Vibriosis in the United States: Projected Health and Economic Impacts for the 21st Century
Environ Health Perspect. 2022 Aug;130(8):87007. doi: 10.1289/EHP9999a. Epub 2022 Aug 19.
BACKGROUND: This paper represents, to our knowledge, the first national-level (United States) estimate of the economic impacts of vibriosis cases as exacerbated by climate change. Vibriosis is an illness contracted through food- and waterborne exposures to various Vibrio species (e.g., nonV. cholerae O1 and O139 serotypes) found in estuarine and marine environments, including within aquatic life, such as shellfish and finfish.
OBJECTIVES: The objective of this study was to project climate-induced changes in vibriosis and associated economic impacts in the United States related to changes in sea surface temperatures (SSTs).
METHODS: For our analysis to identify climate links to vibriosis incidence, we constructed three logistic regression models by Vibrio species, using vibriosis data sourced from the Cholera and Other Vibrio Illness Surveillance system and historical SSTs. We relied on previous estimates of the cost-per-case of vibriosis to estimate future total annual medical costs, lost income from productivity loss, and mortality-related indirect costs throughout the United States. We separately reported results for V. parahaemolyticus, V. vulnificus, V. alginolyticus, and "V. spp.," given the different associated health burden of each.
RESULTS: By 2090, increases in SST are estimated to result in a 51% increase in cases annually relative to the baseline era (centered on 1995) under Representative Concentration Pathway (RCP) 4.5, and a 108% increase under RCP8.5. The cost of these illnesses is projected to reach $5.2 billion annually under RCP4.5, and $7.3 billion annually under RCP8.5, relative to $2.2 billion in the baseline (2018 U.S. dollars), equivalent to 140% and 234% increases respectively.
DISCUSSION: Vibriosis incidence is likely to increase in the United States under moderate and unmitigated climate change scenarios through increases in SST, resulting in a substantial burden of morbidity and mortality, and costing billions of dollars. These costs are mostly attributable to deaths, primarily from exposure to V. vulnificus. Evidence suggests that other factors, including sea surface salinity, may contribute to further increases in vibriosis cases in some regions of the United States and should also be investigated. https://doi.org/10.1289/EHP9999a.
JAMA Health Forum. 2021 Dec 23;2(12):e214283. doi: 10.1001/jamahealthforum.2021.4283. eCollection 2021 Dec.
IMPORTANCE: Brief disruptions in insurance coverage among eligible participants are associated with poorer health outcomes for children.
OBJECTIVE: To describe factors associated with coverage disruptions among children enrolled in North Carolina Medicaid from 2016 to 2018 and estimate the outcome of preventing such disruptions on medical expenditures.
DESIGN SETTING AND PARTICIPANTS: This was a retrospective cohort study using North Carolina Medicaid claims data. All enrolled individuals were aged 1 to 20 years on January 1, 2016, and with 30 days of prior continuous enrollment. Children were observed from January 1, 2016, until December 31, 2018. Analyses were conducted from June 2020 through December 2020.
MAIN OUTCOMES AND MEASURES: Risk of Medicaid coverage disruptions of 1 to less than 12 months was assessed. Among children who disenrolled from Medicaid for 30 or more days, the risk of reenrollment within 1 to 6 months and 7 to 11 months was assessed. An inverse probability of censoring weights method was then used to estimate the outcome of an intervention to reduce coverage disruptions through preventing disenrollment on per member per month (PMPM) cost.
RESULTS: The study population included 831 173 Medicaid beneficiaries aged 1 to 5 years (23%), 6 to 17 years (68%), and 18 to 20 years (9%); 35% were Black, 44% were White, and 14% were Hispanic/Latinx. Among those with a first disenrollment (n = 214 401, 26%), the risk of reenrollment within 6 months and 7 to 11 months was 19% and 7%, respectively. Risk of coverage disruption was higher for Black children (hazard ratio [HR], 1.21; 95% CI, 1.18-1.24), children of other races (Asian, American Indian, Hawaiian or Pacific Islander, multiple races, or unreported; HR, 1.37; 95% CI, 1.33-1.40), and Latinx children (HR, 1.65; 95% CI, 1.60-1.70) compared with White children. Risk of coverage disruption was also higher for children with higher medical complexity (HR, 1.15; 95% CI, 1.12-1.19). The risk of coverage disruption was lower for children living in counties with the highest unemployment rates (HR, 0.89; 95% CI, 0.85-0.94), and comparisons between county-level measures of child poverty and graduation rates showed little or no difference. The estimated PMPM cost for the full population under a scenario in which all medical costs were included was $125.73. Estimated PMPM cost for the full cohort in a counterfactual scenario in which disenrollment was prevented was slightly lower ($122.14). Across all subgroups, estimated PMPM costs were modestly lower ($2-$8) in the scenario in which disenrollment was prevented.
CONCLUSIONS AND RELEVANCE: In this cohort study, the risk of Medicaid coverage disruption was high, with many eligible children in historically marginalized communities continuing to experience unstable enrollment. In addition to improving health outcomes, preventing coverage gaps through policies that decrease disenrollment may also reduce Medicaid costs.
Sequence Polymorphisms in <em>Vibrio cholerae</em> HapR Affect Biofilm Formation under Aerobic and Anaerobic Conditions
Appl Environ Microbiol. 2022 Aug 15:e0104422. doi: 10.1128/aem.01044-22. Online ahead of print.
We investigated the influence of hapR sequence mutations on the biofilm formation of Vibrio cholerae. In this study, hapR sequences from 85 V. cholerae strains belonging to both pandemic and nonpandemic serogroup were investigated through phylogenetic and sequence analyses. Biofilm formation assays under aerobic and anaerobic conditions were also performed. Sequence variations include single point mutations and insertions/deletions (indels) leading to either truncated or frameshifted HapR. Population structure analysis revealed two major hapR haplogroups, hapR1 and hapR2. Phylogenetic reconstruction displayed a hypothetical ancestral hapR sequence located within the hapR1 haplogroup. Higher numbers of single nucleotide polymorphisms and genetic diversity indices were observed in hapR1, while indels occurred dominantly in hapR2. Aerobic conditions supported more robust biofilms compared to anaerobic conditions. Strains with frameshifted HapR produced the largest amount of biofilm under both oxygen conditions. Quantitative real-time PCR assay confirmed that strains with truncated and frameshifted HapR resulted in a nonfunctional regulator as exhibited by the significantly low hapA gene expression. The present study shows that HapR mutations had a strong influence on biofilm formation and that sequence polymorphisms leading to the disruption of DNA-binding sites or dimerization of the HapR will result in more-robust V. cholerae biofilms. IMPORTANCE Our study revealed an ancestral hapR sequence from a phylogenetic reconstruction that displayed the evolutionary lineage of the nonpandemic to the pandemic strains. Here, we established hapR1 and hapR2 as major hapR haplogroups. The association of the O1 and O139 serogroups with the hapR2 haplogroup demonstrated the distinction of hapR2 in causing cholera infection. Moreover, mutations in this regulator that could lead to the disruption of transcription factor-binding sites or dimerization of the HapR can significantly affect the biofilm formation of V. cholerae. These observations on the relationship of the hapR polymorphism and V. cholerae biofilm formation will provide additional considerations for future biofilm studies and insights into the epidemiology of the pathogen that could ultimately help in the surveillance and mitigation of future cholera disease outbreaks.
Prevalence and Distribution of Potentially Human Pathogenic <em>Vibrio</em> spp. on German North and Baltic Sea Coasts
Front Cell Infect Microbiol. 2022 Jul 22;12:846819. doi: 10.3389/fcimb.2022.846819. eCollection 2022.
Global ocean warming results in an increase of infectious diseases including an elevated emergence of Vibrio spp. in Northern Europe. The European Centre for Disease Prevention and Control reported annual periods of high to very high risks of infection with Vibrio spp. during summer months along the North Sea and Baltic Sea coasts. Based on those facts, the risk of Vibrio infections associated with recreational bathing in European coastal waters increases. To obtain an overview of the seasonal and spatial distribution of potentially human pathogenic Vibrio spp. at German coasts, this study monitored V. cholerae, V. parahaemolyticus, and V. vulnificus at seven recreational bathing areas from 2017 to 2018, including the heat wave event in summer 2018. The study shows that all three Vibrio species occurred in water and sediment samples at all sampling sites. Temperature was shown to be the main driving factor of Vibrio abundance, whereas Vibrio community composition was mainly modulated by salinity. A species-specific rapid increase was observed at water temperatures above 10°C, reaching the highest detection numbers during the heat wave event with abundances of 4.5 log10 CFU+1/100 ml of seawater and 6.5 log10 CFU+1/100 g of sediment. Due to salinity, the dominant Vibrio species found in North Sea samples was V. parahaemolyticus, whereas V. vulnificus was predominantly detected in Baltic Sea samples. Most detections of V. cholerae were associated with estuarine samples from both seas. Vibrio spp. concentrations in sediments were up to three log higher compared to water samples, indicating that sediments are an important habitat for Vibrio spp. to persist in the environment. Antibiotic resistances were found against beta-lactam antibiotics (ampicillin 31%, cefazolin 36%, and oxacillin and penicillin 100%) and trimethoprim-sulfamethoxazole (45%). Moreover, isolates harboring pathogenicity-associated genes such as trh for V. parahaemolyticus as well as vcg, cap/wcv, and the 16S rRNA-type B variant for V. vulnificus were detected. All sampled V. cholerae isolates were identified as non-toxigenic non-O1/non-O139 serotypes. To sum up, increasing water temperatures at German North Sea and Baltic Sea coasts provoke elevated Vibrio numbers and encourage human recreational water activities, resulting in increased exposure rates. Owing to a moderate Baltic Sea salinity, the risk of V. vulnificus infections is of particular concern.
Genomic dissection of the <em>Vibrio cholerae</em> O-serogroup global reference strains: reassessing our view of diversity and plasticity between two chromosomes
Microb Genom. 2022 Aug;8(8). doi: 10.1099/mgen.0.000860.
Approximately 200 O-serogroups of Vibrio cholerae have already been identified; however, only 2 serogroups, O1 and O139, are strongly related to pandemic cholera. The study of non-O1 and non-O139 strains has hitherto been limited. Nevertheless, there are other clinically and epidemiologically important serogroups causing outbreaks with cholera-like disease. Here, we report a comprehensive genome analysis of the whole set of V. cholerae O-serogroup reference strains to provide an overview of this important bacterial pathogen. It revealed structural diversity of the O-antigen biosynthesis gene clusters located at specific loci on chromosome 1 and 16 pairs of strains with almost identical O-antigen biosynthetic gene clusters but differing in serological patterns. This might be due to the presence of O-antigen biosynthesis-related genes at secondary loci on chromosome 2.
Antibiotic resistance genes in the gut microbiota of mothers and linked neonates with or without sepsis from low- and middle-income countries
Nat Microbiol. 2022 Aug 4. doi: 10.1038/s41564-022-01184-y. Online ahead of print.
Early development of the microbiome has been shown to affect general health and physical development of the infant and, although some studies have been undertaken in high-income countries, there are few studies from low- and middle-income countries. As part of the BARNARDS study, we examined the rectal microbiota of 2,931 neonates (term used up to 60 d) with clinical signs of sepsis and of 15,217 mothers screening for blaCTX-M-15, blaNDM, blaKPC and blaOXA-48-like genes, which were detected in 56.1%, 18.5%, 0% and 4.1% of neonates' rectal swabs and 47.1%, 4.6%, 0% and 1.6% of mothers' rectal swabs, respectively. Carbapenemase-positive bacteria were identified by MALDI-TOF MS and showed a high diversity of bacterial species (57 distinct species/genera) which exhibited resistance to most of the antibiotics tested. Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae/E. cloacae complex, the most commonly found isolates, were subjected to whole-genome sequencing analysis and revealed close relationships between isolates from different samples, suggesting transmission of bacteria between neonates, and between neonates and mothers. Associations between the carriage of antimicrobial resistance genes (ARGs) and healthcare/environmental factors were identified, and the presence of ARGs was a predictor of neonatal sepsis and adverse birth outcomes.
Differences in epidemiology of enteropathogens in children pre- and post-rotavirus vaccine introduction in Kilifi, coastal Kenya
Gut Pathog. 2022 Aug 1;14(1):32. doi: 10.1186/s13099-022-00506-z.
BACKGROUND: Kenya introduced Rotarix® (GlaxoSmithKline Biologicals, Rixensart, Belgium) vaccination into its national immunization programme beginning July 2014. The impact of this vaccination program on the local epidemiology of various known enteropathogens is not fully understood.
METHODS: We used a custom TaqMan Array Card (TAC) to screen for 28 different enteropathogens in 718 stools from children aged less than 13 years admitted to Kilifi County Hospital, coastal Kenya, following presentation with diarrhea in 2013 (before vaccine introduction) and in 2016-2018 (after vaccine introduction). Pathogen positivity rate differences between pre- and post-Rotarix® vaccination introduction were examined using both univariate and multivariable logistic regression models.
RESULTS: In 665 specimens (92.6%), one or more enteropathogen was detected, while in 323 specimens (48.6%) three or more enteropathogens were detected. The top six detected enteropathogens were: enteroaggregative Escherichia coli (EAggEC; 42.1%), enteropathogenic Escherichia coli (EPEC; 30.2%), enterovirus (26.9%), rotavirus group A (RVA; 24.8%), parechovirus (16.6%) and norovirus GI/GII (14.4%). Post-rotavirus vaccine introduction, there was a significant increase in the proportion of samples testing positive for EAggEC (35.7% vs. 45.3%, p = 0.014), cytomegalovirus (4.2% vs. 9.9%, p = 0.008), Vibrio cholerae (0.0% vs. 2.3%, p = 0.019), Strongyloides species (0.8% vs. 3.6%, p = 0.048) and Dientamoeba fragilis (2.1% vs. 7.8%, p = 0.004). Although not reaching statistical significance, the positivity rate of adenovirus 40/41 (5.8% vs. 7.3%, p = 0.444), norovirus GI/GII (11.2% vs. 15.9%, p = 0.089), Shigella species (8.7% vs. 13.0%, p = 0.092) and Cryptosporidium spp. (11.6% vs. 14.7%, p = 0.261) appeared to increase post-vaccine introduction. Conversely, the positivity rate of sapovirus decreased significantly post-vaccine introduction (7.8% vs. 4.0%, p = 0.030) while that of RVA appeared not to change (27.4% vs. 23.5%, p = 0.253). More enteropathogen coinfections were detected per child post-vaccine introduction compared to before (mean: 2.7 vs. 2.3; p = 0.0025).
CONCLUSIONS: In this rural Coastal Kenya setting, childhood enteropathogen infection burden was high both pre- and post-rotavirus vaccination introduction. Children who had diarrheal admissions post-vaccination showed an increase in coinfections and changes in specific enteropathogen positivity rates. This study highlights the utility of multipathogen detection platforms such as TAC in understanding etiology of childhood acute gastroenteritis in resource-limited regions.