The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a viral infection characterized by high transmissibility. It has rapidly spread across the globe, reaching more than 191 countries and territories since it first emerged in late 2019.
The virus primarily spreads through respiratory droplets and aerosols. In some cases, contact transmission also occurs when people touch contaminated surfaces. Though the virus can spread at a fast rate, it can easily be deactivated by proper disinfection.
In a recent study, researchers at the Public Health Agency of Canada found that dry fog fumigation using peracetic acid (PAA) completely deactivated SARS-CoV-2 on all nine of their test surfaces.
Fumigation to decontaminate surfaces
Surface (or fomite) contamination has been tied to many COVID-19 outbreaks – on cruise ships, schools, sports facilities, and long-term care centers. Though manual disinfection is useful to combat the virus spread, it can be time-consuming and difficult.
Usually, surface contamination is performed using various liquid disinfectants to clean surfaces such as tables, chairs, and other commonly touched areas. Employees who perform liquid disinfection are often exposed to hazardous chemicals.
Decontamination by fumigation using a gas, vapor, or fine mist is effective on all surfaces, including hard-to-reach areas.
The research, which was released on the pre-print bioRxiv* server, shows that decontamination by fumigation using peracetic acid (PAA) successfully deactivated SARS-CoV-2 on nine healthcare facility surfaces, which were experimentally decontaminated with the virus.
Peracetic acid or PAA is a strong oxidant and excellent microbicide. It has been used for many years to deactivate pathogens such as bacterial spores, fungi, and viruses. It is widely used in the food industry, particularly during food processing, as it does not contain toxic by-products.
In healthcare settings, PAA is used to disinfect endoscopes, sterilize bone allografts, and decontaminate surfaces to reduce the risk of nosocomial infections.
To arrive at the study findings, the researchers experimentally contaminated nine surfaces with more than 106 TCID50 of SARS-CoV-2. These surfaces include latex painted wood, stainless steel, computer keyboard button, unsealed hardwood, melamine countertop, vinyl flooring, clear plastic, faux leather, and smartphone touch screens.
The researchers evaluated the effectiveness of PAA fumigation on these surfaces. They found that dry fog fumigation using PAA is a low-tech, portable, and cost-effective decontamination tool that can be used to disinfect large areas within a short period. It will help reduce the workload of staff who cleans clinics and hospital wards.
Furthermore, it was revealed that the method worked well in deactivating the SARS-CoV-2 virus due to the nine test surfaces, including the rooms that housed them.
Using this method can help reduce the risk of transmission in healthcare settings and in public areas where known outbreaks were reported.
“Standard surface decontaminating processes, including sprays and wipes, are laborious and often cannot completely decontaminate sensitive electronic equipment,” the researchers wrote in the paper.
“The ease of use, low cost, and overall effectiveness of a PAA dry fogging suggest it should be considered for decontaminating settings, particularly intensive care units where severely ill SARS-CoV-2 patients are cared for,” they added.
COVID-19 global toll
Infection control measures are crucial in the fight against the coronavirus pandemic. Developing ways to make disinfection better, faster, more cost-effective and safer can help hospitals maximize their workforce and equipment, especially given that second waves of infection are being reported globally.
To date, there are more than 67.7 million cases of COVID-19 and more than 1.54 million deaths. The United States remains the nation with the highest case toll, topping 14.95 million, followed by India, with over 9.7 million cases. Brazil, Russia, and France also reported skyrocketing cases, reaching 6.62 million, 2.49 million, and 2.34 million cases, respectively.
bioRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.