https://www.scientificamerican.com/article/coronavirus-news-roundup-july-4-july-9/

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The World Health Organization (WHO) quickly responded to a group of researchers’ essay published early this week (7/6/20) urging public health authorities to acknowledge that SARS-CoV-2 can spread by way of small droplets that float in the air ("aerosol transmission” or “airborne transmission"), reports Dyani Lewis for Nature (7/8/20). The WHO said on 7/7/20 that “it will issue new guidelines about transmission in settings with close contact and poor ventilation,” Lewis’s story states. And then on 7/9/20, the agency acknowledged in an online post that aerosol or airborne transmission takes place not only in hospital settings but also in other indoor settings, several media outlets reported [it looks like Apoorva Mandavilli at The New York Times broke the news; here also is coverage by Hilary Brueck at Business Insider]. The influential agency’s move holds implications for safety recommendations worldwide related to the new coronavirus, including concerns about: the effectiveness of indoor-air ventilation, filtration, and disinfection; whether cloth face-masks should be worn by the public, particularly indoors; and whether health care workers treating COVID-19 patients should wear tight-fitting N95 respirator masks, not just looser-fitting surgical masks. Lewis’s story features some intriguing nuggets, including the details of disputes about aerosols evidence and descriptions of case studies that provide “circumstantial evidence" of aerosol transmission for SARS-CoV-2.