Detection of poliovirus infection in children with acute gastroenteritis in Chiang Mai, Thailand

Sources, fates and treatment strategies of typical viruses in urban sewage collection/treatment systems: A review

The ongoing coronavirus pandemic (COVID-19) throughout the world has severely threatened the global economy and public health. Due to receiving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from a wide variety of sources (e.g., households, hospitals, slaughterhouses), urban sewage treatment systems are regarded as an important path for the transmission of waterborne viruses. This review presents a quantitative profile of the concentration distribution of typical viruses within wastewater collection systems and evaluates the influence of different characteristics of sewer systems on virus species and concentration. Then, the efficiencies and mechanisms of virus removal in the units of wastewater treatment plants (WWTPs) are summarized and compared, among which the inactivation efficiencies of typical viruses by typical disinfection approaches under varied operational conditions are elucidated. Subsequently, the occurrence and removal of viruses in treated effluent reuse and desalination, as well as that in sewage sludge treatment, are discussed. Potential dissemination of viruses is emphasized by occurrence via aerosolization from toilets, the collection system and WWTP aeration, which might have a vital role in the transmission and spread of viruses. Finally, the frequency and concentration of viruses in reclaimed water, the probability of infection are also reviewed for discussing the potential health risks.

Enteroviruses in gastrointestinal diseases

Gastrointestinal diseases including diarrhoea constitute a major cause of morbidity and mortality in infants and young children especially in developing countries. Worldwide deaths among all ages due to diarrhoea during 2015 were estimated to be about 1.31 million, diarrhoeal deaths in children below 5 years of age being 499 000. Rotavirus accounted for about 200 000 deaths. Although diarrhoeal deaths decreased significantly during the last two decades, they still represent the third largest cause of infantile deaths. Several bacterial, viral, parasitic, fungal and non-infectious diarrhoea causing agents have been identified, but 30% to 40% of diarrhoeal cases remain undiagnosed. Enteroviruses transmit by the faecal-oral route and replicate first in intestinal cells before spreading to the target organ. They have been associated with diarrhoea in a few studies, but their causative role in diarrhoea in humans has not been systematically demonstrated. In view of the recent demonstration that enteroviruses cause diarrhoea in newborn mice pups, thus validating Koch's postulates, the purpose of this review is to emphasise the importance of recognising enteroviruses as major gastrointestinal pathogens associated with acute and persistent diarrhoea and non-diarrhoeal increased frequency of bowel movements in infants, young children and adults. Our studies and several other subsequent studies reported from different countries should stimulate strategies to reduce the burden of infantile gastrointestinal disease, which has hitherto remained unaddressed.