This is why I don't post anything COVID related, so much misinformation on both sides and everyone is an expert... What does it being a US source have to do with anything? What part of "
...respected scientists published in a peer reviewed journal." is political or controversial in anyway? The OP was asking for opinions on face shields for SARS-COV2 protection, here's some real research and not an opinion. Read the original paper if you don't believe the summary in the Washington Post -
https://advances.sciencemag.org/content/early/2020/08/07/sciadv.abd3083.
The latest research indicates that aerosols, and not just droplets, are an important part of SARS-COV2 transmission. Some face coverings are useful for limiting droplet transmission (the above article shows, and ranks, which are better than others), whereas unless they are specifically designed for the purpose (i.e. N95 masks) are effectively useless for preventing the spread of aerosols. There was another article today discussing how experts (microbiologists/epidemiologists, and not Fox news blowhards), who suggest that face coverings are not a one stop panacea even though they still recommend wearing a mask when in public and unable to socially distance, are being labelled as "anti-maskers".
The reason less people are sick now are most likely, in approximate order of importance a) the 2 - 4 week shut down in April / May where most people stayed home where possible prevented anyone who was sick at the time from transmitting; b) almost everyone has been social distancing with people outside their bubble; c) people have been paying closer attention to sanitation (more cognizant of avoiding touching their faces, washing their hands and using hand sanitizer profusely); d) no large gatherings or crowded areas like, schools, sporting events, concerts, limited travel on airplanes and public transport, all of which are perfect places for viruses to spread; e) its summer and not the cold and flu season; f) limited travel outside our communities preventing "new" diseases from coming; and g) wearing masks.
Don't get me wrong, I'm not an anti-masker and wear one if necessary. But I think it is important that when people wear a mask, they wear one that is effective and don't get a false sense of security as there more effective steps to limit viral spread.