Quantitative evaluation of infectious health care wastes from numbers of confirmed, suspected and out-patients during COVID-19 pandemic: A case study of Wuhan.

The fight against coronavirus disease 2019 (COVID-19) is still running its courses. Proper management and disposal of health care wastes (HCWs) are critical to win the fight. To achieve aforementioned tasks, prediction of their production is highly desired. In this study, primary data of production of three kinds of HCWs collected from Wuhan, the first epidemic epicenter worldwide and a mega city with more than 10 million population who has went through a lockdown period of 78 days, were reported for their first time. HCWs were classified into routine HCWs, infectious HCWs (IHCWs) and infectious municipal solid wastes. Among them, infectious HCWs from designated hospitals for COVID-19 were recognized as the most dangerous one. A multiple linear regression (MLR) model was built to predict the production of IHCWs with high significance. Numbers of patients were demonstrated high correlations with the production of IHCWs in an order of confirmed patients ＞ out-patients ＞ suspected patients. By the MLR model, production rates of IHCWs by confirmed, suspected and out patients were determined as 3.2, 1.8 and 0.1 kg/patient, respectively. In addition, constant production of IHCWs during the pandemic period was determined as 13 tons/d. This is the first study on quantitative evaluation of infectious HCWs during COVID-19 pandemic. The achievements in this study have potentials to shed light on global efforts to the prediction, management and disposal of vast HCWs generated in the war against COVID-19.

Make it clean, make it safe: A review on virus elimination via adsorption.

Recently, the potential dangers of viral infection transmission through water and air have become the focus of worldwide attention, via the spread of COVID-19 pandemic. The occurrence of large-scale outbreaks of dangerous infections caused by unknown pathogens and the isolation of new pandemic strains require the development of improved methods of viruses' inactivation. Viruses are not stable self-sustaining living organisms and are rapidly inactivated on isolated surfaces. However, water resources and air can participate in the pathogens' diffusion, stabilization, and transmission. Viruses inactivation and elimination by adsorption are relevant since they can represent an effective and low-cost method to treat fluids, and hence limit the spread of pathogen agents. This review analyzed the interaction between viruses and carbon-based, oxide-based, porous materials and biological materials (e.g., sulfated polysaccharides and cyclodextrins). It will be shown that these adsorbents can play a relevant role in the viruses removal where water and air purification mostly occurring via electrostatic interactions. However, a clear systematic vision of the correlation between the surface potential and the adsorption capacity of the different filters is still lacking and should be provided to achieve a better comprehension of the global phenomenon. The rationalization of the adsorption capacity may be achieved through a proper physico-chemical characterization of new adsorbents, including molecular modeling and simulations, also considering the adsorption of virus-like particles on their surface. As a most timely perspective, the results on this review present potential solutions to investigate coronaviruses and specifically SARS-CoV-2, responsible of the COVID-19 pandemic, whose spread can be limited by the efficient disinfection and purification of closed-spaces air and urban waters.

Emergency response to the explosive growth of health care wastes during COVID-19 pandemic in Wuhan, China.

During the Coronavirus Disease 2019 (COVID-19) as a worldwide pandemic, the security management of health care wastes (HCWs) has attracted increasing concern due to their high risk. In this paper, the integrated management of HCWs in Wuhan, the first COVID-19-outbreaking city with over ten millions of people completely locking down, was collected, investigated and analyzed. During the pandemic, municipal solid wastes (MSWs) from designated hospitals, Fangcang shelter hospitals, isolation locations and residential areas (e.g. face masks) were collected and categorized as HCWs due to the high infectiousness and strong survivability of COVID-19, and accordingly the average production of HCWs per 1000 persons in Wuhan explosively increased from 3.64 kg/d to 27.32 kg/d. Segregation, collection, storage, transportation and disposal of HCWs in Wuhan were discussed and outlined. Stationary facilities, mobile facilities, co-processing facilities (Incineration plants for MSWs) and nonlocal disposal were consecutively utilized to improve the disposal capacity, from 50 tons/d to 280.1 tons/d. Results indicated that stationary and co-processing facilities were preferential for HCWs disposal, while mobile facilities and nonlocal disposal acted as supplementary approaches. Overall, the improved system of HCWs management could meet the challenge of the explosive growth of HCWs production during COVID-19 pandemic in Wuhan. Furthermore, these practices could provide a reference for other densely populated metropolises.