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The cholera outbreak in Yemen: lessons learned and way forward.

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The cholera outbreak in Yemen: lessons learned and way forward.

BMC Public Health. 2018 Dec 04;18(1):1338

Authors: Federspiel F, Ali M

Abstract
The Yemen cholera outbreak has been driven by years of conflict and has now become the largest in epidemiologically recorded history with more than 1.2 million cases since the beginning of the outbreak in April, 2017. In this report we review and discuss the cholera management strategies applied by the major international humanitarian health organizations present in Yemen. We find the response by the organizations examined to have been more focused on case management than on outbreak prevention. Oral Cholera Vaccines (OCVs) were not delivered until nearly 16 months into the outbreak. A recent scale-up of the global OCV stockpile will hopefully allow for rapid mass deployment of the OCV in future humanitarian emergencies. Continuous funding to this stockpile will be crucial to maintain this option for prevention and control of cholera outbreaks. Of equal importance will be the timely recognition of the need for mass OCV deployment and development of more specific, comprehensive and actionable evidence-based frameworks to help guide this decision, however difficult this may be. The outbreak highlights the importance for international humanitarian health organizations to have a continuous discussion about whether and to what extent they should increase their focus on pre-emptively addressing the environmental determinants of communicable diseases in humanitarian emergencies. Strong advocacy from the public health community for peace and the protection of human health, by bringing to attention the public health impacts of armed conflict and keeping the world's political leaders accountable to their actions, will remain crucial.

PMID: 30514336 [PubMed - indexed for MEDLINE]

In silico prediction of drug resistance due to S247R mutation of Influenza H1N1 neuraminidase protein.

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In silico prediction of drug resistance due to S247R mutation of Influenza H1N1 neuraminidase protein.

J Biomol Struct Dyn. 2018 Mar;36(4):966-980

Authors: Mandal RS, Panda S, Das S

Abstract
We present here in silico studies on antiviral drug resistance due to a novel mutation of influenza A/H1N1 neuraminidase (NA) protein. Influenza A/H1N1 virus was responsible for a recent pandemic and is currently circulating among the seasonal influenza strains. M2 and NA are the two major viral proteins related to pathogenesis in humans and have been targeted for drug designing. Among them, NA is preferred because the ligand-binding site of NA is highly conserved between different strains of influenza virus. Different mutations of the NA active site residues leading to drug resistance or susceptibility of the virus were studied earlier. We report here a novel mutation (S247R) in the NA protein that was sequenced earlier from the nasopharyngeal swab from Sri Lanka and Thailand in the year 2009 and 2011, respectively. Another mutation (S247N) was already known to confer resistance to oseltamivir. We did a comparative study of these two mutations vis-a-vis the drug-sensitive wild type NA to understand the mechanism of drug resistance of S247N and to predict the probability of the novel S247R mutation to become resistant to the currently available drugs, oseltamivir and zanamivir. We performed molecular docking- and molecular dynamics-based analysis of both the mutant proteins and showed that mutation of S247R affects drug binding to the protein by positional displacement due to altered active site cavity architecture, which in turn reduces the affinity of the drug molecules to the NA active site. Our analysis shows that S247R may have high probability of being resistant.

PMID: 28279127 [PubMed - indexed for MEDLINE]

Disease and Famine as Weapons of War in Yemen.

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Disease and Famine as Weapons of War in Yemen.

N Engl J Med. 2019 Jan 10;380(2):109-111

Authors: Mohareb AM, Ivers LC

PMID: 30462588 [PubMed - indexed for MEDLINE]

Bacterial contamination and health risks of drinking water from the municipal non-government managed water treatment plants.

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Bacterial contamination and health risks of drinking water from the municipal non-government managed water treatment plants.

Environ Monit Assess. 2018 Oct 29;190(11):685

Authors: Ouf SA, Yehia RS, Ouf AS, Abdul-Rahim RF

Abstract
Water quality and bacterial contamination from 18 drinking water municipal plants in three locations at Giza governorate were investigated. The average total count of bacteria detected after four stages of treatments in the investigated plants was 32 CFU/1 mL compared to 2330 cfu/mL for raw water, with a reduction percentage of 98.6. Although there is a relatively high removal percent of bacterial contamination from the water sources, however, several bacterial pathogens were identified in the produced water prepared for drinking including Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Shigella spp. After 3 days of water incubation at 30 °C, the amount of bacterial endotoxins ranged from 77 to 137 ng/mL in the water produced from the municipal plants compared to 621-1260 ng/mL for untreated water. The main diseases reported from patients attending different clinics and hospitals during summer 2014 at the surveyed locations and assuredly due to drinking water from these plants indicated that diarrheas and gastroenteritis due to E. coli and Campylobacter jejuni constituted 65.7% of the total patients followed by bacillary dysentery or shigellosis due to Shigella spp. (7.9%) and cholera due to Vibrio cholera (7.2%). There was an increase in serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) as well as urea and creatinine values of guinea pigs consuming water produced from the non-governmental plants for 6 months indicating remarkable liver and kidney damages. Histological sections of liver and kidney from the tested animal revealed liver having ballooning degeneration of hepatocytes and distortion and fragmentation of the nuclei, while the section of the kidney showed irregularly distributed wrinkled cells, degenerated Bowman's capsule, congested blood vessels, and inflammatory cells.

PMID: 30374933 [PubMed - indexed for MEDLINE]

The potential impact of case-area targeted interventions in response to cholera outbreaks: A modeling study.

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The potential impact of case-area targeted interventions in response to cholera outbreaks: A modeling study.

PLoS Med. 2018 02;15(2):e1002509

Authors: Finger F, Bertuzzo E, Luquero FJ, Naibei N, Touré B, Allan M, Porten K, Lessler J, Rinaldo A, Azman AS

Abstract
BACKGROUND: Cholera prevention and control interventions targeted to neighbors of cholera cases (case-area targeted interventions [CATIs]), including improved water, sanitation, and hygiene, oral cholera vaccine (OCV), and prophylactic antibiotics, may be able to efficiently avert cholera cases and deaths while saving scarce resources during epidemics. Efforts to quickly target interventions to neighbors of cases have been made in recent outbreaks, but little empirical evidence related to the effectiveness, efficiency, or ideal design of this approach exists. Here, we aim to provide practical guidance on how CATIs might be used by exploring key determinants of intervention impact, including the mix of interventions, "ring" size, and timing, in simulated cholera epidemics fit to data from an urban cholera epidemic in Africa.
METHODS AND FINDINGS: We developed a micro-simulation model and calibrated it to both the epidemic curve and the small-scale spatiotemporal clustering pattern of case households from a large 2011 cholera outbreak in N'Djamena, Chad (4,352 reported cases over 232 days), and explored the potential impact of CATIs in simulated epidemics. CATIs were implemented with realistic logistical delays after cases presented for care using different combinations of prophylactic antibiotics, OCV, and/or point-of-use water treatment (POUWT) starting at different points during the epidemics and targeting rings of various radii around incident case households. Our findings suggest that CATIs shorten the duration of epidemics and are more resource-efficient than mass campaigns. OCV was predicted to be the most effective single intervention, followed by POUWT and antibiotics. CATIs with OCV started early in an epidemic focusing on a 100-m radius around case households were estimated to shorten epidemics by 68% (IQR 62% to 72%), with an 81% (IQR 69% to 87%) reduction in cases compared to uncontrolled epidemics. These same targeted interventions with OCV led to a 44-fold (IQR 27 to 78) reduction in the number of people needed to target to avert a single case of cholera, compared to mass campaigns in high-cholera-risk neighborhoods. The optimal radius to target around incident case households differed by intervention type, with antibiotics having an optimal radius of 30 m to 45 m compared to 70 m to 100 m for OCV and POUWT. Adding POUWT or antibiotics to OCV provided only marginal impact and efficiency improvements. Starting CATIs early in an epidemic with OCV and POUWT targeting those within 100 m of an incident case household reduced epidemic durations by 70% (IQR 65% to 75%) and the number of cases by 82% (IQR 71% to 88%) compared to uncontrolled epidemics. CATIs used late in epidemics, even after the peak, were estimated to avert relatively few cases but substantially reduced the number of epidemic days (e.g., by 28% [IQR 15% to 45%] for OCV in a 100-m radius). While this study is based on a rigorous, data-driven approach, the relatively high uncertainty about the ways in which POUWT and antibiotic interventions reduce cholera risk, as well as the heterogeneity in outbreak dynamics from place to place, limits the precision and generalizability of our quantitative estimates.
CONCLUSIONS: In this study, we found that CATIs using OCV, antibiotics, and water treatment interventions at an appropriate radius around cases could be an effective and efficient way to fight cholera epidemics. They can provide a complementary and efficient approach to mass intervention campaigns and may prove particularly useful during the initial phase of an outbreak, when there are few cases and few available resources, or in order to shorten the often protracted tails of cholera epidemics.

PMID: 29485987 [PubMed - indexed for MEDLINE]

Preventing cholera outbreaks through early targeted interventions.

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Preventing cholera outbreaks through early targeted interventions.

PLoS Med. 2018 02;15(2):e1002510

Authors: von Seidlein L, Deen JL

Abstract
In a Perspective, Lorenz von Seidlein and Jacqueline L. Deen discuss the implications of Andrew Azman and colleagues' accompanying study for management of cholera outbreaks.

PMID: 29485984 [PubMed - indexed for MEDLINE]

Evaluation of integrated disease surveillance and response (IDSR) core and support functions after the revitalisation of IDSR in Uganda from 2012 to 2016.

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Evaluation of integrated disease surveillance and response (IDSR) core and support functions after the revitalisation of IDSR in Uganda from 2012 to 2016.

BMC Public Health. 2019 Jan 09;19(1):46

Authors: Masiira B, Nakiire L, Kihembo C, Katushabe E, Natseri N, Nabukenya I, Komakech I, Makumbi I, Charles O, Adatu F, Nanyunja M, Woldetsadik SF, Fall IS, Tusiime P, Wondimagegnehu A, Nsubuga P

Abstract
BACKGROUND: Uganda is a low income country that continues to experience disease outbreaks caused by emerging and re-emerging diseases such as cholera, meningococcal meningitis, typhoid and viral haemorrhagic fevers. The Integrated Disease Surveillance and Response (IDSR) strategy was adopted by WHO-AFRO in 1998 as a comprehensive strategy to improve disease surveillance and response in WHO Member States in Africa and was adopted in Uganda in 2000. To address persistent inconsistencies and inadequacies in the core and support functions of IDSR, Uganda initiated an IDSR revitalisation programme in 2012. The objective of this evaluation was to assess IDSR core and support functions after implementation of the revitalised IDSR programme.
METHODS: The evaluation was a cross-sectional survey that employed mixed quantitative and qualitative methods. We assessed IDSR performance indicators, knowledge acquisition, knowledge retention and level of confidence in performing IDSR tasks among health workers who underwent IDSR training. Qualitative data was collected to guide the interpretation of quantitative findings and to establish a range of views related to IDSR implementation.
RESULTS: Between 2012 and 2016, there was an improvement in completeness of monthly reporting (69 to 100%) and weekly reporting (56 to 78%) and an improvement in timeliness of monthly reporting (59 to 93%) and weekly reporting (40 to 68%) at the national level. The annualised non-polio AFP rate increased from 2.8 in 2012 to 3.7 cases per 100,000 population < 15 years in 2016. The case fatality rate for cholera decreased from 3.2% in 2012 to 2.1% in 2016. All districts received IDSR feedback from the national level. Key IDSR programme challenges included inadequate numbers of trained staff, inadequate funding, irregular supervision and high turnover of trained staff. Recommendations to improve IDSR performance included: improving funding, incorporating IDSR training into pre-service curricula for health workers and strengthening support supervision.
CONCLUSION: The revitalised IDSR programme in Uganda was associated with improvements in performance. However in 2016, the programme still faced significant challenges and some performance indicators were still below the target. It is important that the documented gains are consolidated and challenges are continuously identified and addressed as they emerge.

PMID: 30626358 [PubMed - in process]

Intelligent judgements over health risks in a spatial agent-based model.

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Intelligent judgements over health risks in a spatial agent-based model.

Int J Health Geogr. 2018 03 20;17(1):8

Authors: Abdulkareem SA, Augustijn EW, Mustafa YT, Filatova T

Abstract
BACKGROUND: Millions of people worldwide are exposed to deadly infectious diseases on a regular basis. Breaking news of the Zika outbreak for instance, made it to the main media titles internationally. Perceiving disease risks motivate people to adapt their behavior toward a safer and more protective lifestyle. Computational science is instrumental in exploring patterns of disease spread emerging from many individual decisions and interactions among agents and their environment by means of agent-based models. Yet, current disease models rarely consider simulating dynamics in risk perception and its impact on the adaptive protective behavior. Social sciences offer insights into individual risk perception and corresponding protective actions, while machine learning provides algorithms and methods to capture these learning processes. This article presents an innovative approach to extend agent-based disease models by capturing behavioral aspects of decision-making in a risky context using machine learning techniques. We illustrate it with a case of cholera in Kumasi, Ghana, accounting for spatial and social risk factors that affect intelligent behavior and corresponding disease incidents. The results of computational experiments comparing intelligent with zero-intelligent representations of agents in a spatial disease agent-based model are discussed.
METHODS: We present a spatial disease agent-based model (ABM) with agents' behavior grounded in Protection Motivation Theory. Spatial and temporal patterns of disease diffusion among zero-intelligent agents are compared to those produced by a population of intelligent agents. Two Bayesian Networks (BNs) designed and coded using R and are further integrated with the NetLogo-based Cholera ABM. The first is a one-tier BN1 (only risk perception), the second is a two-tier BN2 (risk and coping behavior).
RESULTS: We run three experiments (zero-intelligent agents, BN1 intelligence and BN2 intelligence) and report the results per experiment in terms of several macro metrics of interest: an epidemic curve, a risk perception curve, and a distribution of different types of coping strategies over time.
CONCLUSIONS: Our results emphasize the importance of integrating behavioral aspects of decision making under risk into spatial disease ABMs using machine learning algorithms. This is especially relevant when studying cumulative impacts of behavioral changes and possible intervention strategies.

PMID: 29558944 [PubMed - indexed for MEDLINE]

The influence of climate change on waterborne disease and Legionella: a review.

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The influence of climate change on waterborne disease and Legionella: a review.

Perspect Public Health. 2018 Sep;138(5):282-286

Authors: Walker JT

Abstract
Climate change is predicted to have a major impact on people's lives with the recent extreme weather events and varying abnormal temperature profiles across the world raising concerns. The impacts of global warming are already being observed, from rising sea levels and melting snow and ice to changing weather patterns. Scientists state unequivocally that these trends cannot be explained by natural variability in climate alone. Human activities, especially the burning of fossil fuels, have warmed the earth by dramatically increasing concentrations of heat-trapping gases in the atmosphere; as these concentrations increase, the more the earth will warm. Climate change and related extreme weather events are being exacerbated sooner than has previously been considered and are already adversely affecting ecosystems and human health by increasing the burden and type of disease at a local level. Changes to the marine environment and freshwater supplies already affect significant parts of the world's population and warmer temperatures, especially in more temperate regions, may see an increased spread and transmission of diseases usually associated with warmer climes including, for example, cholera and malaria; these impacts are likely to become more severe in a greater number of countries. This review discusses the impacts of climate change including changes in infectious disease transmission, patterns of waterborne diseases and the likely consequences of climate change due to warmer water, drought, higher rainfall, rising sea levels and flooding.

PMID: 30156484 [PubMed - indexed for MEDLINE]

Environmental surveillance for Vibrio cholerae in selected households' water storage systems in Accra Metropolitan Area (AMA) prior to the 2014 cholera outbreak in Accra, Ghana.

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Environmental surveillance for Vibrio cholerae in selected households' water storage systems in Accra Metropolitan Area (AMA) prior to the 2014 cholera outbreak in Accra, Ghana.

Environ Sci Pollut Res Int. 2018 Oct;25(28):28335-28343

Authors: Yirenya-Tawiah DR, Darkwa A, Dzodzomenyo M

Abstract
Cholera is a global public health problem with high endemicity in many developing countries in Africa. In 2014, Ghana experienced its largest epidemic with more than 20,000 cases and 200 deaths; most of it occurred in the Accra Metropolitan Area (AMA). Ghana's disease surveillance system is mainly clinically based and focused on case detection and management. Environmental exploration for the etiological agents is missing from the surveillance strategy. This study therefore assessed the occurrence of toxigenic Vibrio cholerae in water storage systems in selected high risk areas in the AMA area prior to the 2014 outbreak. Three hundred twenty water samples from 80 households' water storage systems were analyzed for toxigenic Vibrio cholerae using the bacterial culture method. Presumptive V. cholerae was isolated from 83.8% of households' water storage systems. The viable cells ranged from 1 to 1400 CFU/100 ml. Vibrio cholerae O1 serotype was isolated from five households in Old Fadama, one household in Shiabu, and one household in Bukom in the month of May and a similar trend was observed for the months of June and July. The presence of Vibro cholerae in the water storage vessels used for drinking confirms the need to consider environmental surveillance for toxigenic Vibro cholerae particularly in high-risk areas to strengthen the existing surveillance system.

PMID: 30083898 [PubMed - indexed for MEDLINE]

Impact of a Large-Scale Handwashing Intervention on Reported Respiratory Illness: Findings from a Cluster-Randomized Controlled Trial.

Impact of a Large-Scale Handwashing Intervention on Reported Respiratory Illness: Findings from a Cluster-Randomized Controlled Trial.

Am J Trop Med Hyg. 2019 Jan 02;:

Authors: Najnin N, Leder K, Forbes A, Unicomb L, Winch PJ, Ram PK, Nizame FA, Arman S, Begum F, Biswas S, Cravioto A, Luby SP

Abstract
We assessed the impact of handwashing promotion on reported respiratory illness as a secondary outcome from among > 60,000 low-income households enrolled in a cluster-randomized trial conducted in Bangladesh. Ninety geographic clusters were randomly allocated into three groups: cholera-vaccine-only; vaccine-plus-behavior-change (handwashing promotion and drinking water chlorination); and control. Data on respiratory illness (fever plus either cough or nasal congestion or breathing difficulty within previous 2 days) and intervention uptake (presence of soap and water at handwashing station) were collected through monthly surveys conducted among a different subset of randomly selected households during the intervention period. We determined respiratory illness prevalence across groups and used log-binomial regression to examine the association between respiratory illness and presence of soap and water in the handwashing station. Results were adjusted for age, gender, wealth, and cluster-randomized design. The vaccine-plus-behavior-change group had more handwashing stations with soap and water present than controls (45% versus 25%; P < 0.001). Reported respiratory illness prevalence was similar across groups (vaccine-plus-behavior-change versus control: 2.8% versus 2.9%; 95% confidence interval [CI]: -0.008, 0.006; P = 0.6; cholera-vaccine-only versus control: 3.0% versus 2.9%; 95% CI: -0.006, 0.009; P = 0.4). Irrespective of intervention assignment, respiratory illness was lower among people who had soap and water present in the handwashing station than among those who did not (risk ratioadjusted: 0.82; 95% CI: 0.69-0.98). With modest uptake of the handwashing intervention, we found no impact of this large-scale intervention on respiratory illness. However, those who actually had a handwashing station with soap and water had less illness. This suggests improving the effectiveness of handwashing promotion in achieving sustained behavior change could result in health benefits.

PMID: 30608050 [PubMed - as supplied by publisher]

Epidemiological description of a protracted cholera outbreak in Tonj East and Tonj North counties, former Warrap State, South Sudan, May-Oct 2017.

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Epidemiological description of a protracted cholera outbreak in Tonj East and Tonj North counties, former Warrap State, South Sudan, May-Oct 2017.

BMC Infect Dis. 2019 Jan 03;19(1):4

Authors: Nsubuga F, Garang SC, Tut M, Oguttu D, Lubajo R, Lodiongo D, Lasuba M, Mpairwe A

Abstract
BACKGROUND: On 18th May 2017, State Ministry of Health of former Warrap State received a report from Tonj East County of an outbreak of acute watery diarrhoea and vomiting in Makuac payam. We conducted this investigation to confirm the causative organism and describe the epidemiology of the outbreak in order to support evidence-based control measures.
METHODS: We defined a suspected case as a resident of Tonj East or Tonj North County with sudden onset of acute watery diarrhoea and vomiting between May 1 and October 15, 2017. A probable case was defined as a suspected case with a positive rapid test for Vibrio cholerae; a confirmed case was a probable case with a positive stool culture for V. cholerae. We conducted systematic case finding by visiting health facilities and villages in the affected payams. We reviewed patient records from 1 May 2017 to 15 October 2017, to identify suspected cholera case-patients. We conducted a descriptive epidemiologic study, examining the distribution of the cases. We computed the attack rates by age, sex, and payam of residence. Case fatality rate was calculated as the ratio of the total number of suspected cholera death to the total number of cholera case-patients. We conducted an oral cholera vaccination campaign after the peak of the outbreak to control and prevent the spread to other payams.
RESULTS: We identified 1451 suspected cholera cases between May and October 2017. Of these, 81% (21/26) had a positive rapid diagnostic test for V. cholerae; out of the 16 rectal swabs transported to the National Public Laboratory, 88% (14/16) were confirmed to be V. cholerae O1 serotype Inaba. The epidemic curve shows continuous common source outbreak with several peaks. The mean age of the case-patients was 24 years (Range: 0.2-75y). The clinical presentations of the case-patients were consistent with cholera. Males had an attack rate of 9.9/10000. The highest attack rate was in ≥30y (14 per 10,000). Among the six payams affected, Makuac had the highest attack rate of 3/100. The case fatality rate (CFR) was 3.0% (44/1451). Paliang and Wunlit had an oral cholera vaccination coverage of ≥100%, while 4 payams had a vaccination coverage of < 90%.
CONCLUSION: This was a continuous common source cholera outbreak caused by V. cholerae 01 sero type Inaba. We recommended strengthening of the surveillance system to improve early detection and effective response.

PMID: 30606126 [PubMed - in process]

Improving rotavirus vaccine coverage: Can newer-generation and locally produced vaccines help?

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Improving rotavirus vaccine coverage: Can newer-generation and locally produced vaccines help?

Hum Vaccin Immunother. 2018 02 01;14(2):495-499

Authors: Deen J, Lopez AL, Kanungo S, Wang XY, Anh DD, Tapia M, Grais RF

Abstract
There are two internationally available WHO-prequalified oral rotavirus vaccines (Rotarix and RotaTeq), two rotavirus vaccines licensed in India (Rotavac and Rotasiil), one in China (Lanzhou lamb rotavirus vaccine) and one in Vietnam (Rotavin-M1), and several candidates in development. Rotavirus vaccination has been rolled out in Latin American countries and is beginning to be deployed in sub-Saharan African countries but middle- and low-income Asian countries have lagged behind in rotavirus vaccine introduction. We provide a mini-review of the leading newer-generation rotavirus vaccines and compare them with Rotarix and RotaTeq. We discuss how the development and future availability of newer-generation rotavirus vaccines that address the programmatic needs of poorer countries may help scale-up rotavirus vaccination where it is needed.

PMID: 29135339 [PubMed - indexed for MEDLINE]

Genomic insights into the 2016-2017 cholera epidemic in Yemen.

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Genomic insights into the 2016-2017 cholera epidemic in Yemen.

Nature. 2019 Jan 02;:

Authors: Weill FX, Domman D, Njamkepo E, Almesbahi AA, Naji M, Nasher SS, Rakesh A, Assiri AM, Sharma NC, Kariuki S, Pourshafie MR, Rauzier J, Abubakar A, Carter JY, Wamala JF, Seguin C, Bouchier C, Malliavin T, Bakhshi B, Abulmaali HHN, Kumar D, Njoroge SM, Malik MR, Kiiru J, Luquero FJ, Azman AS, Ramamurthy T, Thomson NR, Quilici ML

Abstract
Yemen is currently experiencing, to our knowledge, the largest cholera epidemic in recent history. The first cases were declared in September 2016, and over 1.1 million cases and 2,300 deaths have since been reported1. Here we investigate the phylogenetic relationships, pathogenesis and determinants of antimicrobial resistance by sequencing the genomes of Vibrio cholerae isolates from the epidemic in Yemen and recent isolates from neighbouring regions. These 116 genomic sequences were placed within the phylogenetic context of a global collection of 1,087 isolates of the seventh pandemic V. cholerae serogroups O1 and O139 biotype El Tor2-4. We show that the isolates from Yemen that were collected during the two epidemiological waves of the epidemic1-the first between 28 September 2016 and 23 April 2017 (25,839 suspected cases) and the second beginning on 24 April 2017 (more than 1 million suspected cases)-are V. cholerae serotype Ogawa isolates from a single sublineage of the seventh pandemic V. cholerae O1 El Tor (7PET) lineage. Using genomic approaches, we link the epidemic in Yemen to global radiations of pandemic V. cholerae and show that this sublineage originated from South Asia and that it caused outbreaks in East Africa before appearing in Yemen. Furthermore, we show that the isolates from Yemen are susceptible to several antibiotics that are commonly used to treat cholera and to polymyxin B, resistance to which is used as a marker of the El Tor biotype.

PMID: 30602788 [PubMed - as supplied by publisher]

Increase in Reported Cholera Cases in Haiti Following Hurricane Matthew: An Interrupted Time Series Model.

Increase in Reported Cholera Cases in Haiti Following Hurricane Matthew: An Interrupted Time Series Model.

Am J Trop Med Hyg. 2018 Dec 26;:

Authors: Hulland E, Subaiya S, Pierre K, Barthelemy N, Pierre JS, Dismer A, Juin S, Fitter D, Brunkard J

Abstract
Matthew, a category 4 hurricane, struck Haiti on October 4, 2016, causing widespread flooding and damage to buildings and crops, and resulted in many deaths. The damage caused by Matthew raised concerns of increased cholera transmission particularly in Sud and Grand'Anse departments, regions which were hit most heavily by the storm. To evaluate the change in reported cholera cases following Hurricane Matthew on reported cholera cases, we used interrupted time series regression models of daily reported cholera cases, controlling for the impact of both rainfall, following a 4-week lag, and seasonality, from 2013 through 2016. Our results indicate a significant increase in reported cholera cases after Matthew, suggesting that the storm resulted in an immediate surge in suspect cases, and a decline in reported cholera cases in the 46-day post-storm period, after controlling for rainfall and seasonality. Regression models stratified by the department indicate that the impact of the hurricane was regional, with larger surges in the two most highly storm-affected departments: Sud and Grand'Anse. These models were able to provide input to the Ministry of Health in Haiti on the national and regional impact of Hurricane Matthew and, with further development, could provide the flexibility of use in other emergency situations. This article highlights the need for continued cholera prevention and control efforts, particularly in the wake of natural disasters such as hurricanes, and the continued need for intensive cholera surveillance nationally.

PMID: 30594260 [PubMed - as supplied by publisher]

Cholera epidemic in Yemen, 2016-18: an analysis of surveillance data.

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Cholera epidemic in Yemen, 2016-18: an analysis of surveillance data.

Lancet Glob Health. 2018 06;6(6):e680-e690

Authors: Camacho A, Bouhenia M, Alyusfi R, Alkohlani A, Naji MAM, de Radiguès X, Abubakar AM, Almoalmi A, Seguin C, Sagrado MJ, Poncin M, McRae M, Musoke M, Rakesh A, Porten K, Haskew C, Atkins KE, Eggo RM, Azman AS, Broekhuijsen M, Saatcioglu MA, Pezzoli L, Quilici ML, Al-Mesbahy AR, Zagaria N, Luquero FJ

Abstract
BACKGROUND: In war-torn Yemen, reports of confirmed cholera started in late September, 2016. The disease continues to plague Yemen today in what has become the largest documented cholera epidemic of modern times. We aimed to describe the key epidemiological features of this epidemic, including the drivers of cholera transmission during the outbreak.
METHODS: The Yemen Health Authorities set up a national cholera surveillance system to collect information on suspected cholera cases presenting at health facilities. Individual variables included symptom onset date, age, severity of dehydration, and rapid diagnostic test result. Suspected cholera cases were confirmed by culture, and a subset of samples had additional phenotypic and genotypic analysis. We first conducted descriptive analyses at national and governorate levels. We divided the epidemic into three time periods: the first wave (Sept 28, 2016, to April 23, 2017), the increasing phase of the second wave (April 24, 2017, to July 2, 2017), and the decreasing phase of the second wave (July 3, 2017, to March 12, 2018). We reconstructed the changes in cholera transmission over time by estimating the instantaneous reproduction number, Rt. Finally, we estimated the association between rainfall and the daily cholera incidence during the increasing phase of the second epidemic wave by fitting a spatiotemporal regression model.
FINDINGS: From Sept 28, 2016, to March 12, 2018, 1 103 683 suspected cholera cases (attack rate 3·69%) and 2385 deaths (case fatality risk 0·22%) were reported countrywide. The epidemic consisted of two distinct waves with a surge in transmission in May, 2017, corresponding to a median Rt of more than 2 in 13 of 23 governorates. Microbiological analyses suggested that the same Vibrio cholerae O1 Ogawa strain circulated in both waves. We found a positive, non-linear, association between weekly rainfall and suspected cholera incidence in the following 10 days; the relative risk of cholera after a weekly rainfall of 25 mm was 1·42 (95% CI 1·31-1·55) compared with a week without rain.
INTERPRETATION: Our analysis suggests that the small first cholera epidemic wave seeded cholera across Yemen during the dry season. When the rains returned in April, 2017, they triggered widespread cholera transmission that led to the large second wave. These results suggest that cholera could resurge during the ongoing 2018 rainy season if transmission remains active. Therefore, health authorities and partners should immediately enhance current control efforts to mitigate the risk of a new cholera epidemic wave in Yemen.
FUNDING: Health Authorities of Yemen, WHO, and Médecins Sans Frontières.

PMID: 29731398 [PubMed - indexed for MEDLINE]

Crisis-driven cholera resurgence switches focus to oral vaccine.

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Crisis-driven cholera resurgence switches focus to oral vaccine.

Bull World Health Organ. 2018 Jul 01;96(7):446-447

Authors:

Abstract
Oral rehydration was once the mainstay of treatment for cholera, but today's cholera outbreaks fuelled by conflict and instability require a new approach. Sophie Cousins reports.

PMID: 29962546 [PubMed - indexed for MEDLINE]

Forecasting the size and peak of cholera epidemic in Yemen, 2017.

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Forecasting the size and peak of cholera epidemic in Yemen, 2017.

Future Microbiol. 2018 03;13:399-402

Authors: Nishiura H, Tsuzuki S, Asai Y

PMID: 29464968 [PubMed - indexed for MEDLINE]

Association between post-diagnostic use of cholera vaccine and risk of death in prostate cancer patients.

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Association between post-diagnostic use of cholera vaccine and risk of death in prostate cancer patients.

Nat Commun. 2018 06 18;9(1):2367

Authors: Ji J, Sundquist J, Sundquist K

Abstract
Recent evidence suggests that cholera toxin might have multiple functions regarding the ability to regulate the immune system. However, it is unknown whether subsequent administration of cholera vaccine might affect the mortality rate in patients with prostate cancer. Here we report that patients in Sweden, who were diagnosed with prostate cancer between July 2005 and December 2014 and used cholera vaccine, have a decreased risk of death from prostate cancer (HR, 0.57; 95% CI, 0.40-0.82) as compared to patients with prostate cancer but without cholera vaccine use, adjusted for a range of confounding factors. In addition, patients using cholera vaccine show a decreased risk of death overall (HR, 0.53; 95% CI, 0.41-0.69). The decreased mortality rate is largely consistent, irrespective of patients' age or tumor stage at diagnosis. In this population-based study, we suggest that subsequent administration of cholera vaccine after prostate cancer diagnosis might reduce the mortality rate.

PMID: 29915319 [PubMed - indexed for MEDLINE]

Guidelines for the management of paediatric cholera infection: a systematic review of the evidence.

Related Articles

Guidelines for the management of paediatric cholera infection: a systematic review of the evidence.

Paediatr Int Child Health. 2018 11;38(sup1):S16-S31

Authors: Williams PCM, Berkley JA

Abstract
Background Vibrio cholerae is a highly motile Gram-negative bacterium which is responsible for 3 million cases of diarrhoeal illness and up to 100,000 deaths per year, with an increasing burden documented over the past decade. Current WHO guidelines for the treatment of paediatric cholera infection (tetracycline 12.5 mg/kg four times daily for 3 days) are based on data which are over a decade old. In an era of increasing antimicrobial resistance, updated review of the appropriate empirical therapy for cholera infection in children (taking account of susceptibility patterns, cost and the risk of adverse events) is necessary. Methods A systematic review of the current published literature on the treatment of cholera infection in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was undertaken. International clinical guidelines and studies pertaining to adverse effects associated with treatments available for cholera infection were also reviewed. Results The initial search produced 256 results, of which eight studies met the inclusion criteria. Quality assessment of the studies was performed as per the Grading of Recommendations Assessment, Development and Evaluation guidelines. Conclusions In view of the changing non-susceptibility rates worldwide, empirical therapy for cholera infection in paediatric patients should be changed to single-dose azithromycin (20 mg/kg), a safe and effective medication with ease of administration. Erythromycin (12.5 mg/kg four times daily for 3 days) exhibits similar bacteriological and clinical success and should be listed as a second-line therapy. Fluid resuscitation remains the cornerstone of management of paediatric cholera infection, and prevention of infection by promoting access to clean water and sanitation is paramount.

PMID: 29790841 [PubMed - indexed for MEDLINE]

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