Waterborne Epidemics Research Articles

Water quality assessment and evaluation of human health risk of drinking water in Ranchi District of Jharkhand

The primary cause of water-borne disease epidemics, particularly in underdeveloped nations, is the consumption of drinking water tainted with dangerous bacteria that originated in excrement. Water bodies have been essential to the development of civilizations throughout history, and they are still important for the modern economic expansion of all modern cultures. Microbes can get into water sources through agricultural inputs and rainfall runoff, which can combine with sewage effluents. The coliform group of bacteria, which signals the possible presence of harmful organisms, is the organism that is typically searched for during the standard water analysis technique. Microbes that cause disease in humans multiply and spread through the medium of water. For this reason, one of the most crucial criteria for public health is the drinking of safe water. Water samples were collected from various sources (surface water and groundwater sources) throughout March to May 2023. Ten water samples were taken from the surface and groundwater in and around Ranchi Municipality Nagra Toli and Karamtoli areas The MPN index, fungal tests, colony count, and other biochemical test parameters were all analyzed. Comparing surface water to groundwater, it was discovered that the MPN index of the former was higher. Up to 140 MPN/100 mL of total coliform count were found. Samples of surface and groundwater revealed the presence of two distinct bacterial species. It becomes clear that Escherichia coli and Bacillus Enterococcus faecalis bacterial isolates were common. The current study's objectives were to identify the various microbial groups and perform several microbiological studies. To maintain the hygienic quality of the water supply, it is strongly advised to do bacteriological examinations on both the water entering the distribution system and the water already in the system on a frequent and regular basis. Regular inspections are necessary for both sanitary management and testing portable water.

Miniaturized detection devices powered by various heaters: A quick review under the background of water-borne disease epidemics

With the progress of society and the development of productivity, the problem of water pollution and water shortage caused by water pollution is becoming more and more serious. Water-borne diseases caused by pathogenic microorganisms also bring great harm to human beings and other life forms. These microorganisms include bacteria, viruses, protozoa, and parasitic pathogens. Traditional detection methods are time-consuming and costly, and can’t meet the needs of water resource detection. Therefore, there is an urgent need for accurate, rapid, specific, and portable detection equipment for detecting pathogenic microorganisms in water. We analyzed and sorted out the detection methods and detection equipment for detecting pathogenic microorganisms that cause water-borne diseases, summarized these detection methods and detection equipment, and analyzed the advantages and disadvantages of these detection methods. We reasonably concluded that a good detection method for pathogenic microorganisms in water should have the advantages of low cost, low energy consumption, simple operation, strong specificity, and high portability, which can more easily meet the needs of the water quality detection field. Multifunctional small nucleic acid detection devices have been reported for decades, which reduce the reaction time of nucleic acid amplification from hours to minutes, and these miniaturized devices based on nucleic acid amplification are not only highly specific but also low cost, which is very suitable for resource-limited environments.

Use of nanoparticles, a modern means of drug delivery, against cryptosporidiosis.

Cryptosporidium is a primary cause of waterborne epidemics, despite being previously considered only an opportunistic pathogen. The disease is associated with significant economic losses in humans and animals that are brought on by diarrhea, which frequently causes dehydration. Contact with diseased people or animals, as well as polluted water, is the major cause of infection. Different drugs are used to control the parasites. Nitazoxanide (NTZ), which is an anti-protozoan and anti-viral drug, can be used to control helminths, viruses, and protozoan parasites as a broad-spectrum antibiotic and has been approved by the food and drug authority (FDA). However, the problem is the development of resistance over a period of time in these parasites. Nanoparticles have received significant attention as possible anti-parasitic agents in recent years. By directing medications to specific cellular locations, targeted drug delivery minimizes the side effects of medications. Nanoparticles have demonstrated effectiveness against different Cryptosporidium species. Nanoparticles loaded with NTZ are found to be an effective remedy for C. parvum in young ones and decrease the oocyst count shed in the stools. Additionally, silver nanoparticles have proven to be effective against C. parvum by releasing silver ions that breach the cell wall of the oocyst, causing the escape of intracellular contents and the destruction of sporozoites within the oocyst. Implementing tiny particles for the purification of consuming water from Cryptosporidium is an economical and environmentally sustainable process. However, the use of nanoparticles in medicine requires more research.

Investigating extreme hydrological risk impact on water quality; evidence from Buffalo catchment headwater, Eastern Cape, South Africa

Evidence from increasing mineralization, micropollutant concentrations, waterborne epidemics, an algal boom, and dissolved organic matter has provided substantial evidence that climate change impacts water quality. While the impact of the extreme hydrological event (EHE) on water quality (WQ) has aroused considerable research interest, research uncertainty has been premised on WQ data scarcity, a short time frame, data non-linearity, data structure, and environmental biases on WQ. This study conceptualized a categorical and periodic correlation using confusion matrices and wavelet coherence for varying standard hydrological drought index (SHDI; 1971–2010) and daily WQ series (1977–2011) of four spatially distinct basins. By condensing the WQ variables using chemometric analyses, confusion matrices were assessed by cascading the SHDI series into 2-, 3-, and 5-phase scenarios. 2-phase revealed an overall accuracy (0.43–0.73), sensitivity analysis (0.52–1.00), and Kappa coefficient (− 0.13 to 0.14), which declines substantially with the phase increase, suggesting the disruptive impact of EHE on WQ. Wavelet coherence depicted the substantial ({R}_{n}^{2}left(u,sright)ge 0.5) mid- and long-term (8–32 days; 6–128 days) co-movement of streamflow over WQ, confirming the varying sensitivity of WQ variables. Land use/land cover mapping and the Gibbs diagram corroborate the eventful WQ evolution by EHE and their spatial variability concerning landscape transformation. Overall, the study deduced that hydrologic extreme triggers substantial WQ disruption with dissimilar WQ sensitivity. Consequently, suitable chemometric indicators of EHE impacts such as WQ index, nitrate-nitrogen, and Larson index at designated landscapes were identified for extreme chemodynamics impact assessment. This study proffers a recommendation for monitoring and managing the impact of climate change, floods, and drought on water quality.

Nitazoxanide, Ivermectin, and Artemether effects against cryptosporidiosis in diabetic mice: parasitological, histopathological, and chemical studies.

Human cryptosporidiosis is one of the most significant causes of water borne epidemics of diarrhea worldwide. It is extremely important in immunocompromised hosts and malnourished children as it could cause severe life-threatening diarrhea. Despite the global burden of the disease, there are only few available therapies against cryptosporidiosis. Diabetes mellitus is a common metabolic disorder that impair both the innate and adaptive immune responses of the patient. This study aimed to test the effect of Nitazoxanide, Ivermectin, and Artemether against cryptosporidiosis in diabetic mice. Sixty white albino mice were categorized into 6 groups; 10 mice each: GI: normal non-infected non-treated (healthy- control), GII-GVI (diabetic groups), GII: non-infected non treated (diabetic control), GIII: infected non treated (infected control), GIV: infected and treated with Nitazoxanide (NTZ), GV: infected and treated with Ivermectin (IVC), GVI: infected and treated with Artemether (ART). Parasitological, histopathological, and chemical examinations were done to evaluate the effect of NTZ, IVC, and ART against cryptosporidiosis in diabetic mice. Parasitological examination revealed maximum reduction of oocyst shedding in GVI, while histopathological examination showed the least pathologic changes in GV with mild vascular wall fibrosis and moderate lymphocytic infiltration of islets of Langerhans. Measurement of blood glucose level showed the best results with GIV. Nitazoxanide is effective against cryptosporidiosis in diabetic patients with minimal hyperglycemia, Artemether is especially effective in reducing the oocyst shedding in stool, whereas Ivermectin is associated with the least pathological changes in pancreatic islets of Langerhans.Graphical abstract

Chemical profiling of Verbena officinalis and assessment of its anti-cryptosporidial activity in experimentally infected immunocompromised mice

• Verbena officinalis is an intrinsic supplier for biologically active metabolites comprising flavonoids, phenolic acids, organic acids, phenylethanoids, and coumarins. • Verbena officinalis n -butanol extract was proved to have an effective anti-cryptosporidial activity in the infected immunocompromised mice exceeding the gold standard drug nitazoxanide. • Verbena officinalis n -butanol extract was reported to have a promising anti-inflammatory effect, alleviating pathological changes in the small intestine and the liver of infected immunocompromised mice, exceeding the gold standard drug nitazoxanide. • The combination of Verbena officinalis n -butanol extract, and nitazoxanide gave the best results. Cryptosporidiosis is a global zoonotic infection that causes water-borne epidemics of diarrhea. Nevertheless, there are few available therapies for cryptosporidiosis. However, the gold standard drug nitazoxanide (NTZ) has limited efficacy in malnourished and immunocompromised patients. Furthermore, Verbena officinalis L. is a herbal plant widely used in traditional medicine to cure several health disorders and is recognized to possess numerous therapeutic applications. In the present study, the phytochemical composition of aerial part extract from Verbena officinalis was investigated via LC-ESI-MS/MS. Furthermore, the anti-cryptosporidial activity was also performed using an animal model. Fifty mice were divided into 5 groups; GI: non-infected (Negative control), GII: infected non treated (positive control), GIII: infected, treated with NTZ, GIV: infected, treated with V. officinalis n -butanol extract , GV: infected, treated with a combination of NTZ and V. officinalis. Parasitological examination revealed a highly significant difference ( P -value < 0.001) between GIII, GIV, and GV compared to GII regarding the mean number of Cryptosporidium spp. oocyst in the stool. Moreover, GV showed the best efficacy with a percentage of 87%. Also, histopathological examination showed variable degrees of improvement in the villous broadening, and the inflammatory infiltrates in the small intestine with a reduction of hepatocyte degeneration and mononuclear infiltration in GIII, GIV, and GV compared to GII, with the best results seen in GV. Additionally, the chemical profiling of n -butanol extract identified 16 secondary metabolites comprising flavonoids, phenolic acids, phenylethanoids, and coumarins. In conclusion, V. officinalis is an intrinsic supplier of biologically active metabolites with outstanding anti-parasitic and possible anti-inflammatory effects.

Hepatitis: Screening and Preventive Measures

A significant public health issue around the world is viral hepatitis, which is brought on by infection with one of the hepatitis viruses. Reviewing the information that is currently available suggests that the South-East Asia Region has a high prevalence of infection with hepatitis viruses A–E. Hepatitis A virus seroprevalence rates are high among enterically transmitted viruses in the majority of the Region's countries, albeit they have recently decreased. Hepatitis A clinical cases, particularly severe forms of the disease, have increased as a result of the rise in the average age at first exposure. Hepatitis A vaccination is available, however it has not yet been used in the Region as a public health precaution. Hepatitis E virus infection is extremely prevalent in many nations, where it frequently leads to waterborne epidemics and accounts for about half of all cases of acute viral hepatitis. The risk of these illnesses increases with rapid urbanization's lack of access to clean, safe drinking water, nutritious food, and adequate sanitation. Hepatitis B infection rates among bloodborne hepatitis viruses range from low, intermediate, and high among different nations in the region. Either of these viruses can cause persistent infection. Although frequently asymptomatic, persistent infection with these viruses can cause the development of cirrhosis and liver cancer, which are major causes of death in the region. These infections are especially prevalent in some particular population groups, including as intravenous drug users, those who have received blood transfusions, and people who are immunosuppressed. Additionally, certain regions do not screen blood and blood products for substances that cause viral hepatitis. As a result, acute and chronic hepatitis caused by hepatitis virus infection account for a large portion of the disease burden in the South-East Asia Region and cause over 500 000 fatalities there each year. We can lessen our risk of contracting hepatitis in a variety of ways, including by getting vaccinated against hepatitis A and B, using condoms during sexual contact, not sharing needles when using drugs, maintaining good personal hygiene by thoroughly washing our hands with soap and water, refraining from using infected people's personal items, and exercising caution when visiting places with poor sanitation.

Bibliometric analysis on nanoparticle modified screen-printed carbon electrode for E.coli detection using scopus database

Foodborne and waterborne infections are major causes of worry around the world. Escherichia coli (E. coli) pathogenic strains like O157:H7 are a leading cause of food and water-borne illness epidemics all over the world. E. coli is a pathogen present in the lower intestinal of warm-blooded species, it is used to detect fecal contaminants in specimens collected. Human infections can be caused by even low levels of E. coli O157:H7 (10–100 viable organisms). The standard techniques for food assessment are mainly conducted in centralized laboratories and involve long analysis times and complex instrumentation. Sensors based on screen-printed electrodes (SPEs) had grown in popularity in this context due to their favorable properties, such as ease of use and portability, which allow for quick analysis in point-of-need circumstances. The application of SPE-based sensors in the management of food contamination as beneficial analytical techniques to traditional techniques offers for quick inspection at any step in the food manufacturing process, reducing food waste and preventing foodborne infections. However, a screen-printed electrode (SPE) may not be as durable as a traditional electrode, such as a glassy carbon or gold disc, and the surface of its working electrode is not as perfect as that of a mirror-like polished solid electrode, the advantages of SPEs in terms of cost and size have led to an increase in their use as (bio) sensing transducers in recent years. The field of research for detection of E.coli using sensors is very extensive and actively studied by researchers in this area of interest. Here, publication for E.coli and nanoparticle sensor growth research were analyzed from Scopus databases. The keywords were biosensor, E.coli, screen printed electrode and nanoparticle reported from 2012 to 2021. This bibliometric analysis concluded that E.coli biosensors development involved multidisciplinary collaborations of biology, analytical chemistry, optoelectronics, material science, engineering and data science and each subject area plays an important role in establishing biosensors for E. coli detection.

Deep glance on the antiparasitic anticancer activities of wheat germ oil in chronically infected immunosuppressed mice with cryptosporidiosis.

Cryptosporidium species are the major cause of water-borne epidemics of diarrhea in both developing and developed countries that vary from self-limited in immunocompetent patients to severe life-threatening in the immunocompromised hosts. There was a proven correlation between cryptosporidiosis and colorectal cancers, although, studies in this field are still limited. Wheat germ oil (WGO) is a natural product with a known antiparasitic effect and potential antiproliferative activities. This study aimed to evaluate the antiparasitic and anticancer activities of WGO in chronically infected immunosuppressed mice compared to Nitazoxanide (NTZ). This experimental case-control study was performed in the period from January till September 2021. Eighty immunosuppressed bred laboratory mice were divided into 4 groups, 20 mice each; GI non-infected; negative control(NC), GII infected non treated; positive control (PC), GII infected, and treated with NTZ, GIV infected, and treated with WGO. Parasitological, histopathological, and immunohistochemical examinations were performed with estimating the rate of maximal survival for the study groups. Parasitological examination revealed a marked reduction in the mean Cryptosporidium spp. oocyst counts in the stool of GIV compared to PC, and GIII (P-value < 0.001). Histopathological and immunohistochemical examinations showed the best results with GIV which revealed restoration of normal villous pattern, with no dysplasia or malignancy could be detected. GIV showed the best survival rate compared to PC and GIII. WGO is an extremely promising agent that has an excellent therapeutic effect against cryptosporidiosis with the ability to control the tumorigenesis process in the chronically infected immunosuppressed hosts.

Electro-oxidation treatment of sewage water using mixed metal oxide anodes for microbial decontamination

Electrochemical technologies provide an alluring decentralized wastewater treatment system to remove microbial load from contaminated water. The mixed metal oxide (MMO) anodes used for this electrooxidation (EO) technology are stable due to the presence of titanium, ruthenium, iridium, and platinum oxides. This EO technology works by passing current in the presence of minimum electrolyte concentration, sufficient to kill the bacteria present in sewage and simulated water. This technology can be used in sewage pre-treatment plants so that the microbes present in sewage water will not come into the environment, thus, preventing the spread of an epidemic. The lab-scale electrochemical disinfection experiments were performed under batch conditions to see the inactivation efficacy of the EO system with eight different bacteria (Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Salmonella enterica, Acinetobacter calcoacetius, Serratia marcescens, Listeria sp., Enterococcus faecalis). The results showed that at an optimized condition of current density (2.38 mA/cm2), NaCl concentration (1 g/300 mL), treatment time (2 min), 100% inactivation of all the eight bacteria in simulated water was achieved. Under the same optimized conditions, 100% inactivation was achieved with actual sewage water with a treatment time of 8 min. Further, potassium ion leakage and vital staining tests were performed to confirm the complete inactivation of bacteria. The electrodes used in this study were durable even after 80 cycles, as demonstrated through FE-SEM/EDS, XRD, and Raman spectra. Thus, this developed EO system with inexpensive MMO electrodes would open up new channels in treating waterborne epidemics, especially in healthcare facilities.

Modeling and Mapping Flood Hazard with a Flood Risk Assessment Tool: A Case Study of Austin, Texas

As a hazard, flood is an extremely important indicator of how a city is resilient to waterborne diseases and epidemics. Over many decades, flood as a hazard has been a major factor in inducing displacement of marginalized section of the people. Austin city within Central Texas has been identified as one of the major hotspots for flooding in recent decades. Thus, the objectives of the paper are two folded: 1) Empirically, we analyzed and mapped out the susceptibility levels from the factors of physical environments to assess the risk of urban flooding (rainfall data, surface water bodies and topography); in Austin, Texas and 2) Methodologically, we created a re-useable ArcGIS scripting tool that can be used by researchers to automate the process of flood risk modelling with certain criteria. The paper showcases a novel time sensitive building of a tool which will enable better visibility of flood within the city of Austin.

Development of diagnostic systems for wide range and highly sensitive detection of two waterborne hepatitis viruses from groundwater using the conventional reverse transcription nested PCR assay

Waterborne epidemics of human hepatitis virus A and E (HAV and HEV) have been reported worldwide. Molecular biology techniques, such as reverse transcription polymerase chain reaction (RT-PCR), have been widely used to detect the two hepatitis viruses. However, comparative studies of various types of samples are needed, and different environmental factors, including the low copy pathogens, presence of PCR inhibitors in the sample, unknown non-specific reaction with template, and sequence diversity leading to new variants in viruses, should be considered. In addition, standard positive material is required to determine the accuracy of the PCR and should be able to distinguish between false and real positives. In this study, we developed RT-PCR primer sets and optimised standard templates for HAV and HEV detection to address the above concerns associated with test sensitivity and possible PCR inhibition. Finally, previously reported diagnostic methods of HAV and HEV were compared and an applicability test using groundwater was performed. The nested RT-PCR developed in this study is expected to contribute to assess water safety by monitoring HAV and HEV in non-disinfected water, like groundwater.

Seroprevalence and phylogenetic characterization of hepatitis E virus in pig farms in Southern Italy

Hepatitis E virus (HEV) infection is an emerging public health problem in industrialized countries. The infection is associated with waterborne epidemics and transmitted via faecal-oral route. Zoonotic cases of HEV in humans have increased in Europe, and HEV genotype 3 (HEV-3) is the most frequent among humans and animals. Nevertheless, HEV surveillance in the Italian pig farming industry is patchy. Here, HEV prevalence in pig farms located in the Calabria region in Southern Italy was investigated. A total of 692 serum samples were collected from 26 farms and tested for anti-HEV IgG antibody detection. The percentage of HEV-seropositive pigs was 56.8 %. Small farm size, farrow-to-finishing production, and infrequent cleaning procedures were associated with higher HEV seroprevalence. In 12 of the HEV-seropositive farms, 67 faecal samples were collected and 10 of these (10.6 %) tested positive for HEV RNA. Seven of 10 viral RNA sequences were genotyped for phylogenetic analysis, five of which belonged to subtype HEV-3f and two to subtype HEV-3e. The high HEV seroprevalence and the circulation of HEV-3 strains among domestic pigs in the Calabria region pose a risk for the zoonotic transmission of HEV from pigs to occupational exposed workers.

Exploring the Use of Cognitive Approach in Mitigating Unsafe Excreta Disposal in Turkana County, Kenya

We evaluated the influence of induced behavioural change on the community to adopt safe excreta disposal practices. This study was informed by unmerited programs which are majorly provided by most of the health organisations providing sanitary facilities rather than effective use which have failed to reduce the persistent occurrence of waterborne epidemics due to unsafe excreta disposal. Information sought in this survey was from two distinct populations of triggered and non-triggered villages of Turkana County, Kenya. Purposive sampling was used in identifying triggered and non-triggered villages, while systematic random sampling was used to administer structured questionnaires to respondents from identified sample units. From analysed data, the results showed latrine users from triggered villages were many compared with non-triggered villages. Again, the variable of education level, which showed to be critical, suggesting to influence latrine use among rural communities irrespective of the triggers. The parameter estimator of public health extension services and information sharing means from the neighbourhood showed to be statistically significant in influencing adoption and diffusion of health knowledge. In conclusion, involving health experts in knowledge diffusion and scaling up formal education among communities influences the adoption of safe excreta disposal practices. The significance of random factor in the OLS model, explains omitted and/or unobserved variables and existences of unclearly explained variables, informs the need for further investigation.

Risk factors for sporadic hepatitis E infection: a systematic review and meta-analysis

Hepatitis E virus (HEV) is one of the main causes of viral hepatitis infection worldwide. Sources of contamination can vary greatly according to geographical regions and HEV genotypes. HEV is endemic and responsible for large waterborne epidemics involving human HEV-1 or HEV-2 genotypes in regions with limited sanitation, in contrast to industrialized countries, where HEV is mainly a foodborne zoonosis involving HEV-3 and HEV-4 zoonotic genotypes. Limited data on HEV source attribution are available, and all possible sources and transmission pathways of HEV are not fully identified.A systematic review and a meta-analysis of case-control and cohort studies (including transversal studies) were performed to determine the main risk factors associated with sporadic hepatitis E infection. Suitable scientific articles were identified through a systematic literature search and subjected to a methodological quality assessment. From each study, odds-ratio (OR) measures were extracted/calculated, as well as study characteristics such as population type, design, and risk factor hierarchy. Mixed-effects meta-analyses models were adjusted by population type to appropriate data partitions.Seventy-seven cohort and case-control studies conducted between 1986 and 2016 and investigating risk factors in mixed population, susceptible population, and pregnant women, were included in this meta-analysis. Hepatitis E cases were defined with serological exams and differentiated whenever the serological exam is associated or not with symptoms.This meta-analysis identified the parenteral pathway (blood transfusion, tattooing or IV injection, dialysis or hemodialysis), and routes of infection related to contaminated water, animal contact (occupational exposure) and consumption of foods as relevant risk factors for hepatitis E infection.With regards to the role of food, as suspected and sometimes proven in several studies, pig meat, pork sausages, and game meat are identified as significant risk factors for HEV, in particular undercooked pig meat, or meat preparations containing pig liver. In addition, consumption of shellfish (oysters and mussels), in which HEV can accumulate when water is environmentally contaminated (from animal or human origin), is also associated with the detection of anti-HEV antibodies.The results of this meta-analysis show that symptomatic and infected cases share the most explainable risk factors, and are in agreement with recent studies conducted in Europe. This meta-analysis reveals that some sources such as consumption of insufficiently treated water, shellfish, or vegetables are under-investigated. Future case-control studies should include population at risk but under-investigated, such as transplant recipients, pregnant women and children, and investigate other potential sources of HEV.

HEV Occurrence in Waste and Drinking Water Treatment Plants.

Hepatitis E virus (HEV), particularly zoonotic genotype 3, is present in environmental waters worldwide, especially in industrialized countries. Thus, monitoring the presence of HEV in wastewater treatment plants (WWTPs) is an emerging topic due to the importance of reusing water on a global level. Given the limited data, this study aimed to monitor the occurrence of HEV in influent and effluent water in waste- and drinking-water treatment plants (WWTPs and DWTPs). To this end, different procedures to concentrate HEV in influent and effluent water from WWTPs and DWTPs were initially evaluated. The evaluated procedures resulted in average HEV recoveries of 15.2, 19.9, and 16.9% in influent, effluent, and drinking water samples, respectively, with detection limits ranging from 103 to 104 international units (IU)/L. Then, a one-year pilot study was performed to evaluate the performance of the selected concentration method coupled with three RT-qPCR assays in influent and effluent water samples from four different WWTPs. HEV prevalence in influent water varied based on both the RT-qPCR assay and WWTP, while HEV was not detected in effluent water samples. In addition, HEV prevalence using only RT-qPCR3 was evaluated in influent (n = 62) and effluent samples (n = 52) from four WWTPs as well as influent (n = 28) and effluent (n = 28) waters from two DWTPs. The present study demonstrated that HEV circulated in the Valencian region at around 30.65% with average concentrations of 6.3 × 103 IU/L. HEV was only detected in influent wastewater samples, effluent samples from WWTPs and influent and effluent samples from DWTPs were negative. However, given that the infective dose in waterborne epidemics settings is not yet known and the low sensibility of the assay, unfortunately, no direct conclusion could be achieved on the risk assessment of environmental contamination.

Surface waters as a potential source of Giardia and Cryptosporidium in Serbia

Giardiasis and cryptosporidiosis are recognized by the WHO as important emerging diseases of the 21st century. Symptoms are similar and include diarrhoea and vomiting, which may be severe, even life-threatening, for the immunocompromised and children under five years of age. Between 2013 and 2017, the Institute for Public Health in Serbia recorded 10 waterborne epidemics that manifested as gastrointestinal disease. Routine testing for enteropathogenic bacteria and viruses did not identify the aetiological agents of these outbreaks. As water is not examined for the presence of protozoa in Serbia, we performed a pilot study to analyse samples from four major rivers and their tributaries using a newly implemented methodology for detection of Giardia and Cryptosporidium, based on the ISO 15553:2006 standard. Using immunofluorescence microscopy, Giardia was detected in 10 out of the 31 samples, Cryptosporidium in five, while two samples were positive for both. Presence of G. duodenalis gDNA was confirmed by amplification of the β-giardin gene in eight samples, of which one and two, respectively, were identified by RFLP as potentially zoonotic assemblages A and B. The results suggest that surface water in Serbia may be a potential source of infection and call for more in-depth studies using sophisticated molecular tools.

Why all blood donations should be tested for hepatitis E virus (HEV)

BackgroundHepatitis E is a liver disease caused by a small RNA virus known as hepatitis E virus (HEV). Four major genotypes infect humans, of which genotype 1 and 2 (HEV-1, HEV-2) are endemic mainly in Asia and responsible for waterborne epidemics. HEV-3 and HEV-4 are widely distributed in pigs and can be transmitted to humans mainly by undercooked meat, and contact with pigs. HEV-3 is the main genotype in industrialised countries with moderate climate conditions and object of this debate.Main textWhereas an HEV-3 infection in healthy humans is mostly asymptomatic, HEV-3 can induce chronic infection in immunocompromised individuals and acute-on-chronic liver failure (ACLF) in patients with underlying liver diseases. The number of reported cases of HEV-infections in industrialised nations increased significantly in the last years. Since HEV-3 has been transmitted by blood transfusion to other humans, testing of blood donors has been introduced or introduction is being discussed in some industrialised countries. In this article we summarise the arguments in favour of testing all blood donations for HEV-3.ConclusionThe number of HEV infection in the population and the possibility of HEV transmission by blood transfusion are increasing. Transmission by blood transfusion can be dangerous for the recipients considering their immunosuppressive status, underlying disease or other circumstances requiring blood transfusion. This argues in favour of testing all blood donations for HEV-3 to prevent transmission.

Epidemics caused by contamination of drinking water supplied by public water supply systems in terms of current legislation.

This paper describes and comments on contemporary legislation concerning prevention of epidemics caused by contaminated drinking water from public water supplies in the Czech Republic. Suggestions are made for removing existing legislative shortcomings, clarifying diction of existing laws and expanding sanctions and penalties for health injury caused by providers and operators of public drinking water. The author reflects on improving legislation concerning the compensation of victims of contaminated water with reference to the aftermath of a local epidemic in the Dejvice District of Prague. The issues raised should be addressed since better legislation can significantly contribute to the limitation of water-borne epidemics and their consequences.

Hepatitis E: an underestimated emerging threat.

Hepatitis E virus (HEV) is the most common cause of viral hepatitis in the world. It is estimated that millions of people are infected every year, resulting in tens of thousands of deaths. However, these estimates do not include industrialized regions and are based on studies which employ assays now known to have inferior sensitivity. As such, this is likely to represent a massive underestimate of the true global burden of disease. In the developing world, HEV causes large outbreaks and presents a significant public-health problem. Until recently HEV was thought to be uncommon in industrialized countries, and of little relevance to clinicians in these settings. We now know that this is incorrect, and that HEV is actually very common in developed regions. HEV has proved difficult to study in vitro, with reliable models only recently becoming available. Our understanding of the lifecycle of HEV is therefore incomplete. Routes of transmission vary by genotype and location: endemic regions experience large waterborne epidemics, while sporadic cases in industrialized regions are zoonotic infections likely spread via the food chain. Both acute and chronic infection has been observed, and a wide range of extrahepatic manifestations have been reported. This includes neurological, haematological and renal conditions. As the complete clinical phenotype of HEV infection is yet to be characterized, a large proportion of cases go unrecognized or misdiagnosed. In many cases HEV infection does not feature in the differential diagnosis due to a lack of knowledge and awareness of the disease amongst clinicians. In combination, these factors have contributed to an underestimation of the threat posed by HEV. Improvements are required in terms of recognition and diagnosis of HEV infection if we are to understand the natural history of the disease, improve management and reduce the burden of disease around the world.