Molecular detection and genotypic characterization of enteric adenoviruses in a hospital wastewater

Abstract

Hospital wastewater (HWW) represents a major source of the diffusion of many antibiotics and some toxic pathogenic microorganisms in the aquatic environment. Sanitation services play a critical role in controlling transmission of numerous waterborne pathogens, especially enteric human adenoviruses (HAdVs) that can cause acute gastroenteritis. This study intended to evaluate the human adenoviruses (HAdVs) detection rates, to determine the genotype of these viruses and to assess the efficiency of HAdVs removal in hospital pilot wastewater treatment plant (PWWTP) in Tunis City, Tunisia. Therefore, hospital wastewater samples (n = 102) were collected during the study year from the two biological wastewater treatment techniques: natural oxidizing ponds and the rotating biological disks or biodisks. Nested polymerase chain reaction (Nested PCR) was used to evaluate the HAdVs detection rates. The genotype of HAdVs positive samples was achieved by the sequencing of the PCR products. HAdVs were detected in 64% (65/102) of positive wastewater samples. A substantial increase in the frequencies of HAdVs was observed at the exit of the two wastewater treatment techniques studied. The typing of HAdVs species F showed the occurrence of only HAdVs type 41. This data acquired for the first time in Tunisia showed high persistence and survival of HAdVs in the two biological wastewater treatment techniques experienced, and mainly highlighted the poor virological quality of the treated wastewater intended for recycling, agriculture reuse, and discharges into the natural receiving environments. Consequently, tertiary wastewater treatment appeared necessary in this case to decrease the load of enteric viruses flowing in the water environment.

Human adenoviruses associated with respiratory illness in neonates, infants, and children in the Sousse area of Tunisia

“…Unfortunately, comparison with previous HAdV strains identified in ARIs in Tunisia was not possible as no Tunisian HAdV sequences were published. Here, only sequences concerning enteric or environmental HAdV were available 19,20,49,50 …”

“…Here, only sequences concerning enteric or environmental HAdV were available. 19,20,49,50 Although the multiplex qRT-PCR can detect simultaneously a wide range of respiratory pathogens, low viral loads are probably not indicative of viral pathogenesis. The standard PCR used for typing and sequencing is based on the hexon gene, which allows more specific differentiation of adenoviral subtypes.…”

“…The detection of HAdV and the identification of its pathogenicity in ARIs were poorly reported in North Africa 10‐13 . Although in Tunisia HAdV‐ARIs were previously described, 14‐17 the molecular characterization of this pathogen was only performed in non‐ARIs 18‐21 . This study aimed to assess the severity of HAdV and detected coinfections in neonates, infants, and children hospitalized for ARIs in a Central‐East region of Tunisia.…”

Trends, new insights and perspectives in the treatment of hospital effluents

“…Another hot topic of increasing interest is the removal of pathogens and viruses from healthcare structure effluent ( 47 ), ( 48 ), ( 17 ). The recent public health emergency caused by the Coronavirus highlights this aim and many studies have been carried out in recent months with the first results already being published.…”

Quantification of human adenovirus and norovirus in river water in the north-east of France

“…The most prevalent HAdV type detected in wastewater and surface water is enteric type HAdV41 which causes diarrhoea (Rames et al 2016). Thus, HAdV41 genome was detected in 92% to 96% of wastewater samples positive for HAdVs in Italy (Iaconelli et al 2017a) and Japan (Haramoto et al 2007), and in 100% of the hospital wastewater samples in Tunisia (Ibrahim et al 2018).…”