High Fecal Contamination and High Levels of Antibiotic-Resistant Enterobacteriaceae in Water Consumed in the City of Maputo, Mozambique

Abstract

In the city of Maputo, Mozambique, food and water are often sold on the streets. Street water is packaged, distributed, and sold not paying attention to good hygienic practices, and its consumption is often associated with the occurrence of diarrheal diseases. Coincidentally, the increase of diarrheal diseases promotes the inappropriate use of antibiotics that might cause the emergence of antibiotic-resistant bacterial strains. In this context, the present study aimed to assess the microbiological quality of water sold on the streets of Maputo, as well as the antibiotic resistance profile of selected Enterobacteriaceae isolates. The 118 water samples analyzed were from street home-bottled water (n = 81), municipal water distribution systems (tap water) (n = 25), and selected supply wells in several neighborhoods (n = 12). The samples were analyzed for total mesophilic microorganisms, fecal enterococci, fecal coliforms, Escherichia coli, and Vibrio spp. The results showed a high level of fecal contamination in all types of water samples. In home-bottled water, fecal coliforms were found in 88% of the samples, and E. coli in 66% of the samples. In tap water, fecal coliforms were found in 64%, and E. coli in 28% of the samples. In water from supply wells, fecal coliforms and E. coli were found in 83% of the samples. From 33 presumptive Vibrio spp. colonies, only three were identified as V. fluvialis. The remaining isolates belonged to Aeromonas spp. (n = 14) and Klebsiella spp. (n = 16). Of 44 selected Enterobacteriaceae isolates from water samples (28 isolates of E. coli and 16 isolates of Klebsiella spp.), 45.5% were not susceptible to the beta-lactams ampicillin and imipenem, 43.2% to amoxicillin, and 31.8% to amoxicillin/clavulanic acid. Regarding non-beta-lactam antibiotics, there was a high percentage of isolates with tolerance to tetracycline (52.3%) and azithromycin (31.8%). In conclusion, water in Maputo represents a risk for human health due to its high fecal contamination. This situation is made more serious by the fact that a relatively high percentage of isolates with multidrug resistance (40%) were found among Enterobacteriaceae. The dissemination of these results can raise awareness of the urgent need to reduce water contamination in Maputo and other cities in Mozambique.

Occurrence of Intestinal Parasites of Public Health Significance in Fresh Horticultural Products Sold in Maputo Markets and Supermarkets, Mozambique

“…Another important fact associated with the contamination of horticultural products, is the type of water used for irrigation, which sometimes comes from the sewage disposal. In addition, the absence of toilet or any type of hygiene facilities or even more the inadequate water for personal hygiene [ 69 ], in this area could contribute to the occurrence of the parasites in the fruits and vegetables produced [ 13 , 19 , 66 , 70 , 71 ]. Although we observed the lowest contamination rates in the products tested in the production zone, some pathogenic species ( G. duodenalis and nematodes) were identified.…”

Rotavirus A infection in pre- and post-vaccine period: Risk factors, genotypes distribution by vaccination status and age of children in Nampula Province, Northern Mozambique (2015-2019)

“…Our surveillance has limited information on the conditions that the piped water were stored, or in what extent would be safe for consumption after storage. Most of the Mozambican pipelines are old and damaged in some sections aligned with the fact that are not properly maintained [39,40], which can contribute for contamination of the piped water mainly in flood situation as the supply network are emerged [39,41,42]. A recent study conducted in the capital of the country (Maputo), which analyzed different sources of water (home bottled, piped and supply well water) observed higher microbiological contamination than recommended for human consumption in piped water [42].…”

“…Most of the Mozambican pipelines are old and damaged in some sections aligned with the fact that are not properly maintained [39,40], which can contribute for contamination of the piped water mainly in flood situation as the supply network are emerged [39,41,42]. A recent study conducted in the capital of the country (Maputo), which analyzed different sources of water (home bottled, piped and supply well water) observed higher microbiological contamination than recommended for human consumption in piped water [42]. Although the study was carried out in Maputo, the company that supplies water at the national level is the same.…”

Characterization of Escherichia coli from Water and Food Sold on the Streets of Maputo: Molecular Typing, Virulence Genes, and Antibiotic Resistance

“…Of these, 31 food isolates were recovered from 83 street food samples and isolated according to the ISO 16649-2 [20], as described in Salamandane et al [1]. The other 28 E. coli isolates were recovered according to ISO 9308-1 [21], from a total of 118 water samples consumed in the city of Maputo, including home-bottled street water, tap water, and water from supply wells, as described previously [22]. The evaluation of the microbiological quality of the samples indicated that in general, the samples were unsatisfactory for consumption.…”

“…Biochemical tests were carried out to characterize these presumptive E. coli isolates from chromogenic medium, namely Gram staining, catalase, and oxidase tests [1,22]. Subsequently, molecular identification was performed, targeting the 16S rRNA gene (401 bp) with the AB035924 forward primer (5 CCC CCT GGA CGA AGA CTG A-3 ) and the AB035924 reverse primer (5 -ACC GCT GGC AAC AAA GGA T-3 ), as previously reported [1,22]. Subsequently, the 59 isolates were characterized by antibiotic resistance profiling, PFGE subtyping, and the detection of virulence genes and antibiotic resistance genes as described below.…”