Hum Resour Health. 2023 Feb 1;21(1):6. doi: 10.1186/s12960-023-00796-7.

ABSTRACT

BACKGROUND: Healthcare workers' (HCWs) knowledge of multi-stranded cholera interventions (including case management, water, sanitation, and hygiene (WASH), surveillance/laboratory methods, coordination, and vaccination) is crucial to the implementation of these interventions in healthcare facilities, especially in conflict-affected settings where cholera burden is particularly high. We aimed to assess Nigerian HCWs' knowledge of cholera interventions and identify the associated factors.

METHODS: We conducted a cross-sectional study using a structured interviewer-administered questionnaire with HCWs from 120 healthcare facilities in Adamawa and Bauchi States, North-East Nigeria. A knowledge score was created by assigning a point for each correct response. HCWs' knowledge of cholera interventions, calculated as a score, was recoded for ease of interpretation as follows: 0-50 (low); 51-70 (moderate); ≥ 71 (high). Additionally, we defined the inadequacy of HCWs' knowledge of cholera interventions based on a policy-relevant threshold of equal or lesser than 75 scores for an intervention. Multivariable logistic regression was used to identify the factors associated with the adequacy of knowledge score.

RESULTS: Overall, 490 HCWs participated in the study (254 in Adamawa and 236 in Bauchi), with a mean age of 35.5 years. HCWs' knowledge score was high for surveillance/laboratory methods, moderate for case management, WASH, and vaccination, and low for coordination. HCWs' knowledge of coordination improved with higher cadre, working in urban- or peri-urban-based healthcare facilities, and secondary education; cholera case management and vaccination knowledge improved with post-secondary education, working in Bauchi State and urban areas, previous training in cholera case management and response to a cholera outbreak-working in peri-urban areas had a negative effect. HCWs' knowledge of surveillance/laboratory methods improved with a higher cadre, 1-year duration in current position, secondary or post-secondary education, previous training in cholera case management and response to a cholera outbreak. However, HCWs' current position had both positive and negative impacts on their WASH knowledge.

CONCLUSIONS: HCWs in both study locations recorded a considerable knowledge of multi-stranded cholera interventions. While HCWs' demographic characteristics appeared irrelevant in determining their knowledge of cholera interventions, geographic location and experiences from the current position, training and involvement in cholera outbreak response played a significant role.

PMID:36726147 | PMC:PMC9891191 | DOI:10.1186/s12960-023-00796-7

J Travel Med. 2023 Feb 18;30(1):taad010. doi: 10.1093/jtm/taad010.

NO ABSTRACT

PMID:36715147 | DOI:10.1093/jtm/taad010

BMJ Open. 2023 Jan 30;13(1):e059134. doi: 10.1136/bmjopen-2021-059134.

ABSTRACT

OBJECTIVES: This study was conducted to explore the epidemiology and microbiological pattern of the cholera outbreaks that occurred in Zimbabwe from 2018 to 2019.

STUDY SETTING AND DESIGN: This descriptive study used secondary data of 9971 out of 10 730 suspected cases from the Zimbabwean National Diseases Surveillance system and microbiology data of 241 out of 371 patients from the National Microbiology Reference Laboratory in Harare, for the period 5 September 2018 and 3 January 2019. Descriptive analysis was performed to describe the characteristics of the outbreak in terms of person, place and time.

RESULTS: A cumulative total of 10 730 suspected, 371 laboratory-confirmed cholera cases and 68 deaths were reported in Zimbabwe through the situation analysis report (sitrep). The attack rate during the outbreak was 174.6 per 100 000 with a case fatality rate of 0.63%. Most cases seen were among adults from Harare province. Antimicrobial sensitivity testing results showed that a multidrug resistant strain of Vibrio cholerae O1, Ogawa serotype was responsible for the outbreak. The treatment of cases was changed from the standard recommended medicine ciprofloxacin to azithromycin as confirmed by the antimicrobial sensitivity test results. Strategies employed to contain the outbreak included mass oral cholera vaccination in the hotspot areas of Harare, provision of improved and appropriate sanitation measures, provision of safe and adequate water, chlorination of water and improved waste management practice.

CONCLUSIONS: The recurrence of a cholera outbreak is a global concern, especially with the emergence of multi-drug resistant strains of the causal organism. Improving water, sanitation, hygiene infrastructure, health system strengthening measures and inter-sectoral collaboration in responding to the cholera outbreak was key to controlling the outbreak.

PMID:36717140 | DOI:10.1136/bmjopen-2021-059134

East Mediterr Health J. 2023 Jan 19;29(1):3-5. doi: 10.26719/2023.29.1.3.

ABSTRACT

Countries in the WHO Eastern Mediterranean Region (EMR) are currently experiencing a resurgence of cholera. As of 31 December 2022, 8 of the 22 Member States in the region - Afghanistan, Islamic Republic of Iran, Iraq, Lebanon, Pakistan, Somalia, Syria, and Yemen - were grappling with outbreaks of cholera and acute watery diarrhoea (AWD). More than 1 000 000 suspected AWD/cholera cases, more than 7500 laboratory-confirmed cases, and 375 cholera-associated deaths were reported across the region in 2022.

PMID:36710608 | DOI:10.26719/2023.29.1.3

Am J Nurs. 2023 Feb 1;123(2):17. doi: 10.1097/01.NAJ.0000919688.58866.9a.

ABSTRACT

Natural and human-made disasters have contributed to the rise in cases.

PMID:36698348 | DOI:10.1097/01.NAJ.0000919688.58866.9a

Microbes Infect. 2023 Jan 22:105100. doi: 10.1016/j.micinf.2023.105100. Online ahead of print.

ABSTRACT

In today's world and mostly in low and middle income countries, S. flexneri and S. sonnei remains the major causative agent of clinical bacillary dysentery. Based on contemporary epidemiology, a tetravalent Outer Membrane Vesicle (OMVs) based immunogen was formulated using the most commonly circulating Shigella strains, namely, S. flexneri 2a, S. flexneri 3a, S. flexneri 6 and S. sonnei I, in a 1:1:1:1 ratio. Adult BALB/c mice were orally immunized in a prime-boost-boost manner. Tetravalent Shigella OMVs immunogen induced significant and persistent serum and mucosal antibodies against OMVs, Outer Membrane Proteins (OMPs) and lipopolysaccharides (LPS). Tetravalent OMVs also primed cell mediated immune response effectively. Protective efficacy against six heterologous Shigella strains was checked in an intra-peritoneal mouse model. Immunized mice survived lethal infection better than the non-immunized mice cohort with fewer replicating bacteria isolated from their gut. This study establishes the possibilities of tetravalent OMVs immunogen to become a potent vaccine candidate against human shigellosis, overcoming the limitations of sero-specific cross-protection of Shigella species.

PMID:36696935 | DOI:10.1016/j.micinf.2023.105100

Am J Trop Med Hyg. 2023 Jan 23;108(3):518-523. doi: 10.4269/ajtmh.21-0708. Print 2023 Mar 1.

ABSTRACT

Most cholera outbreaks in Bangladesh are seasonal, peaking in the dry and post-monsoon periods. Therefore, we investigated whether changes in water, sanitation, and hygiene (WASH) behavior in three populations in Bangladesh during the year could help explain why these two periods are particular to cholera transmission. The study used a mixed-method design, including a repeated cross-sectional study, focus group discussions, and key informant interviews. Through a repeated cross-sectional study, WASH-related variables were assessed during the dry, monsoon, and control seasons in 600 households from coastal Satkhira, inland Sirajganj, and the Dhaka slums. Seasonal behavioral changes were observed in all study areas. Dhaka and Satkhira had an increased mean distance to water sources during the dry and monsoon seasons (Dhaka: control season, 12 m [95% CI, 11-13]; dry season, 36 m [95% CI, 18-55]; and monsoon season, 180 m [95% CI, 118-243]; Satkhira: control season, 334 m [95% CI, 258-411]; dry season, 669 m [95% CI, 515-822]; and monsoon season, 2,437 m [95% CI, 1,665-3,209]). The participants attributed this to pollution of the usual water source. Perceived water quantity was lowest during the dry season in Dhaka and Sirajganj, and during the monsoon season in Satkhira. Handwashing with soap declined in all areas during the dry and monsoon seasons. Open defecation was frequent among children younger than 5 years, increasing during seasonal climate hazards. Results show that WASH-related behavior changed seasonally, increasing the risk of cholera transmission through multiple hygiene-related transmission pathways. Future research would benefit by ensuring that the length of studies covers all seasons throughout the year and also by looking in more detail at people's behavior and hygiene practices.

PMID:36689946 | PMC:PMC9978562 | DOI:10.4269/ajtmh.21-0708

Microbiol Spectr. 2023 Feb 14;11(1):e0263122. doi: 10.1128/spectrum.02631-22. Epub 2023 Jan 23.

ABSTRACT

Cholera caused by pathogenic Vibrio cholerae is still considered one of the major health problems in developing countries including those in Asia and Africa. Australia is known to have unique V. cholerae strains in Queensland waterways, resulting in sporadic cholera-like disease being reported in Queensland each year. We conducted virulence and antimicrobial genetic characterization of O1 and non-O1, non-O139 V. cholerae (NOVC) strains (1983 to 2020) from Queensland with clinical significance and compared these to environmental strains that were collected as part of a V. cholerae monitoring project in 2012 of Queensland waterways. In this study, 87 V. cholerae strains were analyzed where O1 (n = 5) and NOVC (n = 54) strains from Queensland and international travel-associated NOVC (n = 2) (61 in total) strains were sequenced, characterized, and compared with seven previously sequenced O1 strains and 18 other publicly available NOVC strains from Australia and overseas to visualize the genetic context among them. Of the 61 strains, three clinical and environmental NOVC serogroup strains had cholera toxin-producing genes, namely, the CTX phage (identified in previous outbreaks) and the complete Vibrio pathogenicity island 1. Phylogenetic analysis based on core genome analysis showed more than 10 distinct clusters and interrelatedness between clinical and environmental V. cholerae strains from Australia. Moreover, 30 (55%) NOVC strains had the cholix toxin gene (chxA) while only 11 (20%) strains had the mshA gene. In addition, 18 (34%) NOVC strains from Australia had the type three secretion system and discrete expression of type six secretion system genes. Interestingly, four NOVC strains from Australia and one NOVC strain from Indonesia had intSXT, a mobile genetic element. Several strains were found to have beta-lactamase (blaCARB-9) and chloramphenicol acetyltransferase (catB9) genes. Our study suggests that Queensland waterways can harbor highly divergent V. cholerae strains and serve as a reservoir for various V. cholerae-associated virulence genes which could be shared among O1 and NOVC V. cholerae strains via mobile genetic elements or horizontal gene transfer. IMPORTANCE Australia has its own V. cholerae strains, both toxigenic and nontoxigenic, that are associated with cholera disease. This study aimed to characterize a collection of clinical and environmental NOVC strains from Australia to understand their virulence and antimicrobial resistance profile and to place strains from Australia in the genetic context of international strains. The findings from this study suggest the toxigenic V. cholerae strains in the Queensland River water system are of public health concern. Therefore, ongoing monitoring and genomic characterization of V. cholerae strains from the Queensland environment are important and would assist public health departments to track the source of cholera infection early and implement prevention strategies for future outbreaks. Understanding the genomics of V. cholerae could also inform the natural ecology and evolution of this bacterium in natural environments.

PMID:36688638 | PMC:PMC9927259 | DOI:10.1128/spectrum.02631-22

BMC Public Health. 2023 Jan 23;23(1):152. doi: 10.1186/s12889-023-15051-w.

ABSTRACT

BACKGROUND: Histo-blood group antigens (HBGAs) which include the ABO and Lewis antigen systems have been known for determining predisposition to infections. For instance, blood group O individuals have a higher risk of severe illness due to V. cholerae compared to those with non-blood group O antigens. We set out to determine the influence that these HBGAs have on oral cholera vaccine immunogenicity and seroconversion in individuals residing within a cholera endemic area in Zambia.

METHODOLOGY: We conducted a longitudinal study nested under a clinical trial in which samples from a cohort of 223 adults who were vaccinated with two doses of Shanchol™ and followed up over 4 years were used. We measured serum vibriocidal geometric mean titers (GMTs) at Baseline, Day 28, Months 6, 12, 24, 30, 36 and 48 in response to the vaccine. Saliva obtained at 1 year post vaccination was tested for HBGA phenotypes and secretor status using an enzyme-linked immunosorbent assay (ELISA).

RESULTS: Of the 133/223 participants included in the final analysis, the majority were above 34 years old (58%) and of these, 90% were males. Seroconversion rates to V. cholerae O1 Inaba with non-O (23%) and O (30%) blood types were comparable. The same pattern was observed against O1 Ogawa serotype between non-O (25%) and O (35%). This trend continued over the four-year follow-up period. Similarly, no significant differences were observed in seroconversion rates between the non-secretors (26%) and secretors (36%) against V. cholerae O1 Inaba. The same was observed for O1 Ogawa in non-secretors (22%) and the secretors (36%).

CONCLUSION: Our results do not support the idea that ABO blood grouping influence vaccine uptake and responses against cholera.

PMID:36690955 | DOI:10.1186/s12889-023-15051-w

Microorganisms. 2023 Jan 12;11(1):193. doi: 10.3390/microorganisms11010193.

ABSTRACT

Many antibiotic-resistant bacteria carry resistance genes on conjugative plasmids that are transferable to commensals and pathogens. We determined the ability of multiple enteric bacteria to acquire and retransfer a broad-host-range plasmid RP4. We used human-derived commensal Escherichia coli LM715-1 carrying a chromosomal red fluorescent protein gene and green fluorescent protein (GFP)-labeled broad-host-range RP4 plasmid with ampR, tetR, and kanR in in vitro matings to rifampicin-resistant recipients, including Escherichia coli MG1655, Dec5α, Vibrio cholerae, Pseudomonas putida, Pseudomonas aeruginosa, Klebsiella pneumoniae, Citrobacter rodentium, and Salmonella Typhimurium. Transconjugants were quantified on selective media and confirmed using fluorescence microscopy and PCR for the GFP gene. The plasmid was transferred from E. coli LM715-1 to all tested recipients except P. aeruginosa. Transfer frequencies differed between specific donor-recipient pairings (10-2 to 10-8). Secondary retransfer of plasmid from transconjugants to E. coli LM715-1 occurred at frequencies from 10-2 to 10-7. A serial passage plasmid persistence assay showed plasmid loss over time in the absence of antibiotics, indicating that the plasmid imposed a fitness cost to its host, although some plasmid-bearing cells persisted for at least ten transfers. Thus, the RP4 plasmid can transfer to multiple clinically relevant bacterial species without antibiotic selection pressure.

PMID:36677486 | DOI:10.3390/microorganisms11010193

BMJ. 2023 Jan 19;380:p141. doi: 10.1136/bmj.p141.

NO ABSTRACT

PMID:36657787 | DOI:10.1136/bmj.p141

Math Biosci Eng. 2022 Aug 25;19(12):12427-12447. doi: 10.3934/mbe.2022580.

ABSTRACT

In this paper, we consider an age-structured cholera model with saturation incidence, vaccination age of vaccinated individuals, infection age of infected individuals, and biological age of pathogens. First, the basic reproduction number is calculated. When the basic reproduction number is less than one, the disease-free equilibrium is locally stable. Further, the existence of backward bifurcation of the model is obtained. Numerically, we also compared the effects of various control measures, including basic control measures and vaccination, on the number of infected individuals.

PMID:36654005 | DOI:10.3934/mbe.2022580

New Microbes New Infect. 2022 Dec 23;51:101077. doi: 10.1016/j.nmni.2022.101077. eCollection 2023 Jan.

NO ABSTRACT

PMID:36654941 | PMC:PMC9841269 | DOI:10.1016/j.nmni.2022.101077

JAMA. 2023 Jan 17;329(3):200. doi: 10.1001/jama.2022.23551.

NO ABSTRACT

PMID:36648460 | DOI:10.1001/jama.2022.23551

Rev Environ Health. 2023 Jan 16. doi: 10.1515/reveh-2022-0201. Online ahead of print.

ABSTRACT

OBJECTIVES: Cholera has a long history in India and Bangladesh, the region where six out of the past seven global pandemics have been seeded. The changing climate and growing population have led to global cholera cases remaining high despite a consistent improvement in the access to clean water and sanitation. We aim to provide a holistic overview of variables influencing environmental cholera transmission within the context of India and Bangladesh, with a focus on the mechanisms by which they act.

CONTENT: We identified 56 relevant texts (Bangladesh n = 40, India n = 7, Other n = 5). The results of the review found that cholera transmission is associated with several socio-economic and environmental factors, each associated variable is suggested to have at least one mediating mechanism. Increases in ambient temperature and coastal sea surface temperature support cholera transmission via increases in plankton and a preference of Vibrio cholerae for warmer waters. Increased rainfall can potentially support or reduce transmission via several mechanisms.

SUMMARY AND OUTLOOK: Common issues in the literature are co-variance of seasonal factors, limited access to high quality cholera data, high research bias towards research in Dhaka and Matlab (Bangladesh). A specific and detailed understanding of the relationship between SST and cholera incidence remains unclear.

PMID:36639850 | DOI:10.1515/reveh-2022-0201

J Glob Health. 2023 Jan 14;13:03004. doi: 10.7189/jogh.13.03004.

NO ABSTRACT

PMID:36637804 | DOI:10.7189/jogh.13.03004

MMWR Morb Mortal Wkly Rep. 2023 Jan 13;72(2):21-25. doi: 10.15585/mmwr.mm7202a1.

ABSTRACT

On September 30, 2022, after >3 years with no confirmed cholera cases (1), the Directorate of Epidemiology, Laboratories and Research (DELR) of the Haitian Ministry of Public Health and Population (Ministère de la Santé Publique et de la Population [MSPP]) was notified of two patients with acute, watery diarrhea in the metropolitan area of Port-au-Prince. Within 2 days, Haiti's National Public Health Laboratory confirmed the bacterium Vibrio cholerae O1 in specimens from the two patients with suspected cholera infection, and an outbreak investigation began immediately. As of January 3, 2023, >20,000 suspected cholera cases had been reported throughout the country, and 79% of patients have been hospitalized. The moving 14-day case fatality ratio (CFR) was 3.0%. Cholera, which is transmitted through ingestion of water or food contaminated with fecal matter, can cause acute, severe, watery diarrhea that can rapidly lead to dehydration, shock, and death if not treated promptly (2). Haiti is currently facing ongoing worsening of gang violence, population displacement, social unrest, and insecurity, particularly in the metropolitan area of Port-au-Prince, including Belair, Bas-Delmas, Centre-Ville, Martissant, Cité Soleil, Croix-des Bouquets, and Tabarre, creating an environment that has facilitated the current resurgence of cholera (3). This report describes the initial investigation, ongoing outbreak, and public health response to cholera in Haiti. Cholera outbreak responses require a multipronged, multisectoral approach including surveillance; case management; access to safe water, sanitation, and hygiene (WASH) services; targeted oral cholera vaccine (OCV) campaigns; risk communication; and community engagement. This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.

PMID:36634024 | DOI:10.15585/mmwr.mm7202a1

Zhonghua Yi Shi Za Zhi. 2022 Nov 28;52(6):354-361. doi: 10.3760/cma.j.cn112155-20220621-00091.

ABSTRACT

The cholera epidemic in 1919 started from coastal cities in the south of China and the cities near Russia in the north. It centered on those cities with relatively developed economies with well-developed transportation, and spread along railway lines and coastal lines in both directions to the North and the South, based on the reports in Ta Kung Pao. It covered 14 provinces, the municipalities under the Central Government and the special administrative regions. To prevent and control the 1919 cholera epidemic, the Republic of China government took some effective measures, such as reminding people of prevention, providing medical assistance, controlling the flow of people and cutting off transmission routes. It was found that some serious issues were exposed in the process of preventing and controlling the 1919 cholera epidemic, such as corrupt government, the ignorance of part of the population and poor medical services and technology. Analysing the historical materials of the 1919 cholera epidemic and summarising its experience and lessons in Ta Kung Pao can provide references for future epidemic prevention and control.

PMID:36624676 | DOI:10.3760/cma.j.cn112155-20220621-00091

Mar Pollut Bull. 2023 Feb;187:114521. doi: 10.1016/j.marpolbul.2022.114521. Epub 2023 Jan 7.

ABSTRACT

Human vibriosis, caused by pathogenic Vibrio spp., such as Vibrio parahaemolyticus, Vibrio cholerae and Vibrio vulnificus, has been increasing worldwide, mediated by increasing consumption of seafood. The present study was conducted to examine the global prevalence of V. vulnificus, V. parahaemolyticus and V. cholerae in fishes. We searched PubMed, Web of Science, Scopus, and CNKI for peer-reviewed articles and dissertations prior to December 31, 2021. A total of 24,831 articles were retrieved, and 82 articles contained 61 fish families were included. The global pooled prevalence of V. cholerae, V. parahaemolyticus and V. vulnificus in fishes was 9.56 % (95 % CI: 2.12-20.92), 24.77 % (95 % CI: 17.40-32.93) and 5.29 % (95 % CI: 0.38-13.61), respectively. Subgroup and meta-regression analyses showed that study-level covariates, including temperature, country, continent, origin and detection methods partly explained the between-study heterogeneity. These heterogeneities were underpinned by differences of the three Vibrio spp. in fishes at geographical and climatic scales. These results reveal a high global prevalence of pathogenic Vibrio spp. in fishes and highlight the need for implementation of more effective prevention and control measures to reduce food-borne infection in humans.

PMID:36621299 | DOI:10.1016/j.marpolbul.2022.114521

Int J Mol Sci. 2022 Dec 28;24(1):531. doi: 10.3390/ijms24010531.

ABSTRACT

Oral immunization with the choleric toxin (CT) elicits a high level of protection against its enterotoxin activities and can control cholera in endemic settings. However, the complete B-cell epitope map of the CT that is responsible for protection remains to be clarified. A library of one-hundred, twenty-two 15-mer peptides covering the entire sequence of the three chains of the CT protein (CTP) was prepared by SPOT synthesis. The immunoreactivity of membrane-bound peptides with sera from mice vaccinated with an oral inactivated vaccine (Schankol™) allowed the mapping of continuous B-cell epitopes, topological studies, multi-antigen peptide (MAP) synthesis, and Enzyme-Linked Immunosorbent Assay (ELISA) development. Eighteen IgG epitopes were identified; eight in the CTA, three in the CTB, and seven in the protein P. Three V. cholera specific epitopes, Vc/TxA-3, Vc/TxB-11, and Vc/TxP-16, were synthesized as MAP4 and used to coat ELISA plates in order to screen immunized mouse sera. Sensitivities and specificities of 100% were obtained with the MAP4s of Vc/TxA-3 and Vc/TxB-11. The results revealed a set of peptides whose immunoreactivity reflects the immune response to vaccination. The array of peptide data can be applied to develop improved serological tests in order to detect cholera toxin exposure, as well as next generation vaccines to induce more specific antibodies against the cholera toxin.

PMID:36613974 | DOI:10.3390/ijms24010531