Interplays of a waterborne disease model linking within- and between- host dynamics with waning vaccine-induced immunity

In this paper, we propose a multi-scale waterborne disease model and are concerned with a heterogenous process of waning vaccine-induced immunity. A completely nested rule has been adopted to link the within- and between-host systems. We prove the existence, positivity and asymptotical smoothness of the between-host system. We derive the basic reproduction numbers associated with the two-scale system in explicit forms, which completely determine the behavior of each system. Uncertainty analysis reveals the trade-offs of the kinetics of the within-host system and the transmission of the between-host system. Numerical simulations suggest that the vaccine waning process plays a significant role in the estimation of the prevalence at population level. Furthermore, the environmental heterogeneity complicates the transmission patterns at the population level.

Modeling the health impact of water and sanitation service deficits on waterborne disease transmission

Cholera is a waterborne disease that continues to pose serious public health problems in many developing countries. Increasing water and sanitation coverage is a goal for local authorities in these countries, as it can eliminate one of the root causes of cholera transmission. The SIWDR (susceptible–infected–water–dumpsite–recovered) model is proposed here to evaluate the effects of the improved coverage of water and sanitation services in a community at risk of a cholera outbreak. This paper provides a mathematical study of the dynamics of the water and sanitation (WatSan) deficits and their public health impact in a community. The theoretical analysis of the SIWDR model gave a certain threshold value (known as the basic reproductive number and denoted $\mathcal{R}_{0}$ R 0 ) to stop the transmission of cholera. It was found that the disease-free equilibrium was globally asymptotically stable whenever $\mathcal{R}_{0} \leq 1$ R 0 ≤ 1 . The unique endemic equilibrium was globally asymptotically stable whenever $\mathcal{R}_{0} >1$ R 0 > 1 . Sensitivity analysis was performed to determine the relative importance of model parameters to disease transmission and prevention. The numerical simulation results, using realistic parameter values in describing cholera transmission in Haiti, showed that improving the drinking water supply, wastewater and sewage treatment, and solid waste disposal services would be effective strategies for controlling the transmission pathways of this waterborne disease.

An overview of emerging foodborne and waterborne diseases

Several foodborne and waterborne diseases have emerged in the past two decades as a consequence of changes in etiological agents, hosts and the environment. The burden of foodborne and waterborne disease is not uniformly distributed globally:because of the inequitable distribution of the world’s resources some countries carry a disproportionately heavy burden of infectious disease, and what is considered a re-emergent pathogen in one location may be endemic in another

Implementation of a national waterborne disease outbreak surveillance system: overview and preliminary results, France, 2010 to 2019

Background Waterborne disease outbreaks (WBDO) associated with tap water consumption are probably underestimated in France. Aim In order to improve their detection, Santé publique France launched a surveillance system in 2019, based on the periodical analysis of health insurance data for medicalised acute gastroenteritis (mAGE). Methods Spatio-temporal cluster detection methods were applied to mAGE cases to prioritise clusters for further investigation. These investigations determined the plausibility that infection is of waterborne origin and the strength of association. Results Between January 2010 and December 2019, 3,323 priority clusters were detected (53,878 excess mAGE cases). They involved 3,717 drinking water supply zones (WSZ), 15.4% of all French WSZ. One third of these WSZ (33.4%; n = 1,242 WSZ) were linked to repeated clusters. Moreover, our system detected 79% of WBDO voluntarily notified to health authorities. Conclusion Environmental investigations of detected clusters are necessary to determine the plausibility that infection is of waterborne origin. Consequently, they contribute to identifying which WSZ are linked to clusters and for which specific actions are needed to avoid future outbreaks. The surveillance system incorporates three priority elements: linking environmental investigations with water safety plan management, promoting the systematic use of rainfall data to assess waterborne origin, and focusing on repeat clusters. In the absence of an alternative clear hypothesis, the occurrence of a mAGE cluster in a territory completely matching a distribution zone indicates a high plausibility of water origin.

Identifikasi Escherichia coli Penyebab Waterborne Disease pada Air Mimun Kemasan dan Air Mimunm Isi Ulang

Abstrak. Latar Belakang : Depot air minum isi ulang dan air minum kemasan banyak didapati pada daerah perkotaan yang didorong oleh tingginya kebutuhan masyarakat akan air, baik untuk minum maupun dalam kebutuhan sehari-hari lainnya. Air yang terkontaminasi jika dikonsumsi akan menimbulkan suatu penyakit. Tujuan : Mengetahui cemaran bakteri Escherichia coli penyebab waterborne disease pada air minum isi ulang dan air minum kemasan di Kelurahan Kemiling Raya dengan cara peyaringan kemudian mengisolasi dan mengidentifikasi pada media selektif diferensial. Metode : Desain penelitian deskriptif dengan pendekatan kulitatif eksperimetal. Sampel air minum isi ulang dan air minum kemasan disaring dengan penyarig membran kemudia diinkubasi pada media selektif deferensial Chromogenic Coliform Agar untuk mengetahui adanya cemaran bakteri Escherichia coli penyebab waterborne disease. Hasil : Terdapat koloni bakteri Escherichia coli penyebab waterborne disease pada air minum isi ulang pada sampel X, Y, dan Z dengan masing-masing memiliki jumlah 2,4 x 102 cfu/100ml, 6,8 x102 cfu/100ml dan sampel Z memiliki jumlah koloni yang sangat banyak sehingga dikategorikan TBUD, sedangkan untuk sampel W tidak terdapat koloni bakteri. Pada sampel air minum kemasan A dan B memiliki jumlah koloni bakteri Escherichia coli yang sama yaitu sebanyak 2,0 x 100 cfu/250ml. Kesimpulan : Jumlah koloni bakteri Escherichia coli pada sampel air minum isi ulang lebih besar dari pada air minum kemasan. Tidak terdapat bakteri Escherichia coli penyebab waterborne disease pada air minum isi ulang yang menggunakan teknologi reserved osmosis.