@FurnessColin I think we should approach the results of the studies of NO nasal spray with caution. Here is the most recent one: thelancet.com/journals/lanse…@FurnessColin The authors tested for viral clearance using RT-PCR of nasal swabs, ie. they could only determine "clearance of nasal viral RNA". However, SARS-CoV-2 infects the rest of the body - the nasal passage & respiratory tract is only the entry point.