The World Health Organization (WHO) has published a series of documents that relate to the relevance of a series of pathogens in water.
The background documents will inform the revision of WHO guidelines for drinking water quality and on sanitary facilities and health. Examples of covered agents are Cyclospora, Salmonella, Toxoplasma Gondii, Yersinia Enterocolitics, Hepatitis A and E, Cryptosporidium and Shigella.
Strong proof
There is strong evidence that the transfer of linking Non-Typhoid Salmonella With unsafe drinking water, insufficient sanitary facilities and poor hygiene. A number of outbreaks of drinking water have been reported. Polluted food is the most common source of infections, while polluted drinking water is a less common source.
Non-Typhoid Salmonella is mainly transmitted by the faecal route where animals are the primary source. An approach that deals with the management of animal droppings is necessary to control the transmission.
Salmonella is often detected in drinking water samples, especially in low income and where insufficient treatment occurs. Disinfection processes, including chloring, are effective for inactivating salmonella. Storage of drinking water must be protected against faecal contamination by birds and other small animals. E. Coli is a suitable indicator for the possible presence or absence of non-typhidal salmonella in drinking water.
There is also strong evidence for transfer of Toxoplasma gondii Due to unsafe drinking water and multiple outbreaks.
Toxoplasma Gondii can be transferred via the faecal route by consuming food or water that is contaminated with oocysts or through intake or consumption of tissue cysts in raw or not cooked meat from infected animals. Approaches that identify and control fecal contamination of cats along the sanitary facility and drinking water supply chain are needed to manage the risk.
Toxoplasma Gondii is very resistant to chemical disinfectants but is sensitive to UV light. The absence of E. coli is not a suitable indicator for the absence of Toxoplasma Gondii in drinking water. However, the presence of E. coli is a suitable indicator for potential presence.
Other pathogens with strong evidence are typhus salmonella, sapovirus, rotavirus, entamoeba histolytics, adenovirus, giardia duodenalis, cryptosporidium, diarreanagenic E. coli, vibrio cholerae, hepatitis a and e -viruss.
Moderate or low risk
There is moderate evidence that the transfer of linking the transfer of Cyclospora Cayetanensis With unsafe drinking water, insufficient sanitary facilities and poor hygiene. Outbreaks of the drinking water have been documented, but not on the same scale as other pathogens.
Transmission is mainly via the faecal route. Food is the dominant source, but water is a possible source. Cyclospora Cayetanensis causes watery diarrhea, abdominal cramps, weight loss, anorexia, myalgia, fatigue and sometimes vomiting and fever. Infections occur worldwide, but are more common in tropical areas.
Detection of cyclospora via microscopy is complex, resource-intensive and may not distinguish itself between species and viable and non-living oöcysts. Molecular methods cannot determine the viability of oocysts. The absence of E. coli is not a suitable indicator for the absence of Cyclospora Cayetanensis in drinking water. However, its presence is a suitable indicator for the potential presence of Cyclospora.
Other pathogens with moderate evidence are Yersinia Enterocolitics and Burkwolderia Pseudomallei.
Staphylococcus Aureus and Cronobacter Sakazakii are one of the drugs that are considered a low health sign in drinking water.
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