Some weak evidence suggesting that
Covid19 could be seasonal and may not affect tropical regions so badly all other things being equal.
An aerosol of the virus in saliva was tested by a US lab and the results presented to the US coronavirus taskforce. Yesterday, they were presented at the Trump show. The results re sunlight are not surprising. UVC kills life - it disrupts the bonds between molecules in nucleic acids because the energy of the light in this wavelength band are comparable to the energy levels in some atoms in nucleic acids. The results of temperature and humidity are interesting and weren't to my knowledge known.
By the way, no point opening your curtains and bathing your room with sunlight, or turning on the light bulb. Glass blocks UV light. Normal light bulbs don't produce UV light.
This suggests that the virus should struggle in the tropics and should be seasonal, and outside in a hot Summer's day might be quite a safe environment provided you are sensible regarding people.
I wish they had investigated saline conditions.....salt can disrupt membrane and cell wall structures due to osmosis. And of course would be relevant to beaches.
Take the top line as normal conditions inside the house (to be honest I don't know what humidity inside the house is), and then look at how sunlight, increased temperature and increased humidity have on the virus half-life.....the time for half the virus levels to be 'denatured'.
This does not mean that Covid19 cannot thrive on the equator - see how it has spread in the dormitories of migrant workers in Singapore (equator). There thousands of migrant workers have caught the virus.
It should be easier to fight the virus near the equator and in the Northern hemisphere at high latitudes it may return in the Autumn / winter. This is only suggestive. Don't get too carried away with it but I thought it was quite interesting and may have some implications for behaviour and lockdowns. Parks/beaches may not be a bad place to be in the Summer if they are not crowded.
A bright day on snow would be good (skiing) a chalet would not! Snow reflects light - hence skiers are prone to sunburn.
UAE,Qataris, Iranians, Iraqis might be happy to read this.
I am struck though about fevers and body temperature. It does OK in bodies at 98 F.
This is just interesting and slightly suggests that Covid19 may return in the Autumn/Winter where it will survive outside for slightly longer than would otherwise be the case.