Seshadri Ramkumar, Professor, Texas Tech University, USA
Delta variant is a mutant of concern. Double vaccination is shown to have efficacy against multiple variants, but in the case of unvaccinated people, countermeasures such as wearing face masks, hand hygiene are important. In a recent press conference, Dr. Tedros Adhanom Ghebreyesus, Director General of World Health Organization (WHO) stated, “Delta is the most transmissible of the variants identified so far. It has been identified in at least 85 countries and is spreading rapidly among unvaccinated populations.”
This Delta variant is recognized as the cause of recent surge in COVID-19 cases in Sydney- Australia, Bangladesh, and South Africa. Starting on July 1, Bangladesh will be in a strict lockdown under the watchful eyes of its military. Bangladesh just recorded over 8000 cases in a single day making it a record since the pandemic started last year. Sydney is under two-week lockdown to stop the spread of this variant.
While vaccination is the solution, until countries such as South Africa, Bangladesh, and India to name a few have enough vaccines to immunize the population, COVID-19 restrictions such as face covers, physical distancing are needed. In densely populated areas, it may not be perfectly feasible to maintain physical distancing, but for the complete stay at home orders. In such cases, face masks are an important protective measure. A street scene in the Uttara area in Dhaka, Bangladesh reinforces the need for face covers. Due to the increasing number of cases, Israel last Friday reinstated the mask mandate in indoor settings and in large outdoor gatherings.
As the Delta variant is known to be highly contagious and is airborne, for unvaccinated people following COVID-19 safety protocols can save lives. Ongoing research in the Nonwovens and Advanced Materials Laboratory at Texas Tech University has shown that multilayered nonwoven mats with layers made from cotton and absorbent fibers are able to exhibit over 90% filtration efficiency in trapping 30 nm sized aerosols. Corona virus particles normally range between 100-150 nm in diameter and hence nonwoven materials will be able to trap them and can destabilize them depending on the material of the filters. Reports show that cellulosic materials can quickly destabilize Corona virus compared to hard materials such as steel or plastic.
On June 25th, an official from WHO stated, “Vaccine alone won’t stop the community transmission. People need to continue to use masks consistently, be in ventilated spaces, hand hygiene, respiratory etiquette, physical distance, and avoid crowding.”
Masks are important tools in the tool kit to protect people, importantly for those who are unvaccinated and who are immunocompromised.