Occurrence of Human Enteric Viruses in Water Sources and Shellfish: A Focus on Africa

The regular monitoring of water environments is essential for preventing waterborne virus-mediated contamination and mitigating health concerns. We aimed to detect human adenovirus (HAdV) in the Wadi Hanifah (WH) and Wadi Namar (WN) lakes, King Saud University wastewater treatment plant (KSU-WWTP), Manfouha-WWTP, irrigation water (IW), and AnNazim landfill (ANLF) in Riyadh, Saudi Arabia. HAdV hexon sequences were analyzed against 71 HAdV prototypes and investigated for seasonal influence. ANLF had the highest HAdV prevalence (83.3%). Remarkably, the F species of HAdV, especially serotype 41, predominated. Daily temperature ranges (22–45 °C and 10–33 °C) influenced the significance of the differences between the locations. The most significant relationship of ANLF and IW to WH and KSU-WWTP was found at the high-temperature range (p = 0.001). Meanwhile, WN was most correlated to ANLF at the low-temperature range (p < 0.0001). Seasonal influences on HAdV prevalence were insignificant despite HAdV’s high prevalence in autumn and winter months, favoring low temperatures (high: 22–25 °C, low: 14–17 °C) at five out of six locations. Our study provides insightful information on HAdV prevalence and the circulating strains that can address the knowledge gap in the environmental impacts of viruses and help control viral diseases in public health management.

Groundwater samples were collected during April and August 2016 from five hand-dug wells in Soa subdivision, Cameroon, Africa, with the aim to assess the microbiological quality of them and the health risk they (it) posed to the population in the study area. The low piezometric levels (9 – 20 m) and the little variation in curb-stone heights (0.58 – 1.05 m) suggest that the wells are vulnerable to pollution. The physicochemical parameters show that the groundwater of Soa is acidic and poorly mineralized. The residents (population that is) dominated by students are not connected to the supply of water, making them to take recourse to groundwater for potable and general domestic use. Bacteriological analysis of the water samples focused on the search and listing of heterotrophic mesophilic aerobic bacteria (HAMB). Also, bacteria of the Enterobacteriaceae family were isolated, identified and listed (Escherichia, Klebsiella, Shigella, Citrobacter, Providencia). The analyses were carried out through standard, selective and conventional gallery culture media, using surface spreading, streaking and sub-culturing techniques. Different ions were also measured for the physicochemical component according to the usual analytical techniques. The low values of oxidability recorded clearly indicated the organic pollution of the study area. The organic matter was found largely influencing the increase in bacterial load (which is high and varied). The presence of these germs degrades the quality of the water, which varies from one site to the other, with the important factors being the proximity of the sources of pollution to the well and its poor maintenance. As local populations are using these ground waters without any prior treatment, they are prone to health risks over the period time.

Globally, waterborne gastroenteritis attributable to rotaviruses is on the increase due to the rapid increase in population growth, poor socioeconomic conditions, and drastic changes in climatic conditions.