Water-borne infectious disease

Water-Borne Infectious Disease Outbreaks Associated with Water Scarcity and Rainfall Events... 

Table 2 Most important faecal-orai water-borne infectious diseases with their causal agents...

Abundant literature on the increase of the densities of faecal pathogens and indicators in water sources during dry and rainy periods and the significant effect of rain in water-borne infectious disease outbreaks exist and prove all these assertions. 

Very little evidence associating water scarcity and an increase in outbreaks of faecal-oral water-borne infectious diseases exists in developed countries. A recent retrospective study performed in England provides some evidence that both low rainfall and heavy rain precede many drinking water outbreaks [3]. Yet, as stated earlier in this review, the situation is potentially different in developing countries [5-7, 9-12], where water scarcity, including droughts, leads to different circumstances that have a clear incidence in the occurrence of both water-borne and water-washed infectious diseases. 

There are some descriptions of water-borne outbreaks, or even small epidemics of acute gastroenteritis (diarrhoea), cholera and hepatitis E associated with catastrophic floods that occurred in developing countries, such as Sudan [34, 35], Nicaragua [36], Mozambique [37] and West Bengal [37]. On the contrary, no changes in the base-line outbreak incidence have been reported in developed countries after major floods [37, 38]. When infrastructures and water management are adequate, outbreaks of faecal-oral water-borne infectious diseases do not follow flood events, even in the case where water flooding has compromised the security of water facilities [37]. 

Cases and deaths from selected water-borne infectious diseases in the Mediterranean countries are summarized in Table 4.5. Microorganisms which can be pathogenic to man and which are transmitted by contaminated water are discussed below. 

T ble 4.5. Cases (C) and deaths (D) from selected water-borne infectious diseases in Mediterranean countries [65]... 

Use as diluted extract for internal use, as douche, as wash, as nasal spray, as water purifier when traveling in foreign countries or to treat water-borne infectious disease, as disinfectant for sickrooms, medical instruments, hands. 

The water-related or water-associated infectious diseases are typically arranged in four classes from the environmental engineering point of view, although more complex categorizations have also been proposed [14]. These categories are faecal-oral water-borne diseases, water-washed diseases, water-based diseases and diseases transmitted by water-associated insect vectors. Each type has different causes and potential solutions. Too often the term water-borne disease is erroneously used to name all of them without distinction. 

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