Surface waters in northern Tanzania harbor fecal coliform and antibiotic resistant Salmonella spp. capable of horizontal gene transfer

Abstract

Some Salmonella spp. are important pathogenic bacteria that can be transmitted to people via food and water and that can cause disease characterized by mild to severe enteric and systemic illness. In developing countries, infections caused by pathogenic antibiotic resistant Salmonella spp. are a major health challenge, particularly in children. Through the use of membrane filtration and Environmental Protection Agency (EPA) 1200 methods, the presence of fecal coliforms and antibiotic resistant Salmonella spp. in surface water sources was investigated, some of which had shared access for animals and people. Out of 100 water samples, 76 were positive for fecal coliforms and 63% of the positive samples contained >100 CFU / 100 ml of water. We observed a significant positive correlation between the number of fecal coliforms and the presence of Salmonella spp. (r=0.46, n=100, P=0.01). Importantly, >26% of the samples were positive for Salmonella spp. and 88% of these samples harbored isolates resistant to ≥1 antibiotic. Moreover, we found that 26% of antibiotic resistant Salmonella spp. isolates were able to transfer their resistance traits to a recipient strain of Escherichia coli at the rate of 1-7 x 10 -3 per donor cells. Microbiological contamination of water was clearly evident in open water sources from northern Tanzania, and the presence of Salmonella spp. poses an immediate risk to anyone who consumes these waters if untreated.

Infection, colonization and shedding of Campylobacter and Salmonella in animals and their contribution to human disease: A review

“…• Use of untreated water from shared sources • Rain water run-off which washout the faeces from the rangeland towards the water sources • Presence of faeces in human house and children playgrounds Lyimo et al (2016), Bell et al (2015), Cummings et al (2016) Kissing or snuggling with pet birds as mostly practiced by children has been associated with human Salmonella outbreaks (Basler, Nguyen, Anderson, Hancock, & Behravesh, 2016;Behravesh et al, 2014;Gaffga et al, 2012). Campylobacter and Salmonella shedding in cats and dogs is more of a public health concern due to the companion nature of these animals to humans (Andrzejewska, Szczepańska, Klawe, Śpica, & Chudzińska, 2013;Holmberg et al, 2015;Leahy, Cummings, Rodriguez-Rivera, Rankin, & Hamer, 2016;de Massis et al, 2018).…”

“…Campylobacter and Salmonella are recurrently isolated from soil, water bodies, animal houses and effluents Lyimo et al, 2016;Mhongole, Mdegela, Kusiluka, Forslund, & Dalsgaard, 2017;O'Mahony, Buckley, Bolton, Whyte, & Fanning, 2011). Freerange or extensive systems of animal husbandry mostly practiced in rural resource-poor settings, poor slurry management on animal farms and in slaughterhouses result in environmental bacterial contamination ( Figure 1; .…”

“…Indistinguishable strains connected to Campylobacter waterborne outbreaks occurring during heavy rains were documented in humans, cattle and manure implying water source contamination by water run-off from animal farms (Clark et al, 2003). In resource-poor settings, water source sharing between humans and animals is not uncommon resulting in use of water contaminated by animal faeces (Kusiluka et al, 2005;Lyimo et al, 2016;Strauch & Almedom, 2011). The isolation of similar Salmonella strains in domestic and non-domestic animals in rural and urban surface water further confirms animals as reservoirs for environmental and water bacterial contamination (Thomas, Slawson, & Taylor, 2013).…”

Water-Handling Patterns and Associated Microbial Profiles in relation to Hygiene in Babati Town, Tanzania

“…Their presence indicates that the water may be contaminated with human or animal wastes [22]. These bacteria can be found in various water sources which have contact with animals or humans, such as rivers, tanks, taps, and wells and are known to be able to survive for up to more than two weeks [23]. Contamination in these waters can cause illnesses such as diarrhea, cramps, nausea, and headaches, to mention a few.…”

“…In particular, these contaminations are more dangerous to infants, young children, the elderly, and people who are severely immune compromised [22]. In fact, it has been reported elsewhere that the illness and mortality due to waterborne salmonellosis is on the increase in developing countries [23].…”