Recent Cholera Publications on PubMed

Exploring Japanese Kampo medicine in fighting epidemics: discovering and popularising croton and satou as 'specific drugs' to treat cholera

August 25, 2022

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.

PMID:36008309 | DOI:10.3760/cma.j.cn112155-20220617-00087

Heterogeneous Growth Enhancement of Vibrio cholerae in the Presence of Different Phytoplankton Species

August 24, 2022

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.

PMID:36000870 | PMC:PMC9469713 | DOI:10.1128/aem.01158-22

Altered Molecular Attributes and Antimicrobial Resistance Patterns of Vibrio cholerae O1 El Tor Strains Isolated from the Cholera Endemic Regions of India

August 24, 2022

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.

PMID:36000378 | DOI:10.1111/jam.15794

Effectiveness and quality of risk communication process in Ethiopia: The case of risk communication during cholera outbreak in Addis Ababa, Ethiopia

August 19, 2022

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.

PMID:35984824 | PMC:PMC9390904 | DOI:10.1371/journal.pone.0265203

Examining the Relationship between Climate Change and Vibriosis in the United States: Projected Health and Economic Impacts for the 21st Century

August 19, 2022

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.

PMID:35983960 | DOI:10.1289/EHP9999a

Medicaid Coverage Disruptions Among Children Enrolled in North Carolina Medicaid From 2016 to 2018

August 17, 2022

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.

PMID:35977295 | PMC:PMC8796937 | DOI:10.1001/jamahealthforum.2021.4283

Sequence Polymorphisms in <em>Vibrio cholerae</em> HapR Affect Biofilm Formation under Aerobic and Anaerobic Conditions

August 15, 2022

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.

PMID:35969071 | DOI:10.1128/aem.01044-22