*Water Shortages: Cause of Water Safety in Sub-Saharan Africa DOI: http://dx.doi.org/10.5772/intechopen.103927*

Diseases resulting from the use of unsafe water or water stress can be grouped into (i) waterborne diseases (e.g. cholera, typhoid, etc.); (ii) water-related diseases (e.g. malaria, yellow fever, river blindness, sleeping sickness, etc.), (iii) water-based diseases (e.g. guinea worm and bilharzia etc.), (iv) water-scarce diseases (trachoma and scabies, etc.).

Diarrheal diseases be of viral, bacterial, or parasitic origin are the leading cause of human mortality in Africa. Our continent alone contributes to 53% of the diarrheal cases reported globally, with contaminated drinking water being the main source of transmission [40]. In 2016, more than half a billion deaths in SSA were attributed to diarrheal diseases with contamination of drinking water identified as one of the leading risk factors. Mortality due to water stress coupled with poor sanitation and hygiene is projected to substantially increase by 1.5 deaths per 1000 annually by the year 2050 [41]. This is true for countries with high mortality rate such as Angola, Burkina Faso, Burundi, Central African Republic, Chad, DRC, Ethiopia, Guinea Bissau, Liberia, Mali, Niger, Sierra Leone, and Somalia [41] (**Figure 3**). The most devastating waterborne diarrheal disease on the African continent is cholera, which is caused by Vibrio cholera. Cholera is a deadly diarrheal disease that decimates tens of thousands of people annually. Approximately, more than one million cholera cases are reported in Africa [42]. This may explain why 83% of the total deaths due to cholera were from the SSA region [43]. Additionally, a curated database of cholera incidence in SSA from 2010 to 2020 identified 999 suspected cholera outbreaks across 25 SSA countries [44]. Most of the major outbreaks of this disease occurred in countries such as Nigeria, Cameroon, the Democratic Republic of Congo, Kenya, Ethiopia, and Sudan [42–44]. Notably, the collective outbreaks in four countries alone (Democratic Republic of the Congo, Ethiopia, Cameroon, and South Sudan) represented 65% of total outbreaks that occurred in the entire SSA [44]. Besides poor sanitation and hygiene, floods have been recognized as one of the major contributing factors of cholera outbreaks in SSA [45]. This occurs when floods hinder supply of or access to safe water sources, thereby introducing *Vibrio cholerae* even to areas that are usually not affected by this pathogen [46]. The coastal regions of SSA remain the focal areas. Curiously, most of these cholera foci are in densely urbanized areas of Africa with limited access to safe water and adequate sanitation [42].

The most frequently reported parasitic waterborne diseases in SSA are malaria (95%), schistosomiasis (44.8%), giardiasis (23.4%), soil-transmitted helminths (23.4%), and amoebiasis (21.3%) [27, 47]. Recently in 2020, Malaria infected more

than 200 million people in SSA indicating its exponential increase attributed to the interruption of malaria-control services during the awake of Covid-19 pandemics [47, 48]. Parasitic infections via water can be acquired while bathing, washing, drinking water, eating food exposed to contaminated water, or being bitten by an infected vector. Interestingly, the prevalence of important parasitic diseases in several regions of SSA is still high in recent years given that most of these diseases circulate in poor water supply areas [29].

Among bacterial waterborne diseases, typhoid fever features as an important cause of morbidity and mortality with an estimated 12−33 million cases leading to 216,000−600,000 deaths annually [49]. Apart from Benin, Equatorial Guinea, Eritrea, Namibia and Somalia, which did not provide any report on typhoid fever, this bacterial disease is highly prevalent over the whole SSA as highlighted in **Figure 4** [50]. The highest incidence of this disease occurs in areas of high water contamination with human feces, limited water supply due to increased population, urbanization, and weak health systems [51]. An updated data on the burden of typhoid fevers from 2010 to 2013 show that this waterborne disease continues to be high in SSA (**Table 1**), and illustrate the need for control measures such as vaccination, and improvements in water quality, sanitation, and hygiene [52]. Gastroenteritis caused by non-typhoidal *Salmonella* is another important waterborne disease that prevails in SSA. Close to 80% of all the reported cases in 2017 occurred in SSA alone, affecting mainly children under 5, adolescents, and active young people under 50 [53].

Many studies across Africa suggest that coliforms, *Escherichia coli*, *Streptococcus*, *Salmonella*, and *Shigella* spp., *Vibrio cholera*, etc. are major contaminants of alternative sources of water in SSA [31, 37, 39, 42].

In the light of its devastating impacts on health and socio-economic developments in Africa in general and in SSA in particular, water crises come immediately after weapons of mass destruction [16]. Consumption of unsafe water thus poses a major challenge to population health in many countries of SSA.

**Figure 4.** *Prevalence of typhoid fever in sub-Saharan Africa [50].*

