Will it be more effective to use prayer to request removal of the coronavirus COVID-19 from our planet altogether, as opposed to simply asking for protection from infection by the virus and healing of those infected?

This is a brilliant idea you have here. There is a night and day difference in the doability of these two potential preventive measures. Keeping people from being vulnerable to an infection is sometimes challenging for the divine realm simply because of free will choices to be weakened, to be vulnerable, to be unguarded, to be in harm’s way, and to be beyond help even from divine grace. Those who have developed negative God beliefs or feel themselves unworthy of receiving help, that they are trapped in their life and doomed, in effect, with their self-abnegation, their dark wishes for personal suffering and in a downward spiral, this still must be respected and allowed by the divine realm to honor their free will choice to suffer. On the other hand, an alien organism created in a laboratory by aliens to wreak havoc on a planet not their own is the work of interlopers and is much easier to eradicate at the delivery stage rather than preventing or even curing an ongoing infection. People who are ill suffer the same difficulties when the divine realm may be hampered in their ability to come to the rescue, because people themselves, through prior karmic events often involving chronic infections or fatal infectious disease in other lifetimes, are primed to have low expectations of recovery, and in fact their bodies might be configured with their genetic makeup for them to be fragile and easily succumb to infectious illness in the current life as a karmic liability. So attacking the problem on the front end to have the virus removed so what is delivered to the population by those spreading the microbes is actually virus free, would be a very elegant way to slow down the spread of this scourge and potentially eliminate it altogether. The extent to which this can be done will still depend on human energy to make a sufficient sized request to enable the divine realm to go to bat for humans, in effect, against a very large cohort of extraterrestrial beings avidly wanting to see their handiwork do its worst. So it is a contest of free wills in play here. We are sympathetic to the human cause, but all have some rights here and all have a say in things energetically at the present time. The virus itself is a scourge and an interloper that does not belong, so this is a point of vulnerability in the scheme being launched here, that we can more easily neutralize a weapon than the intent of the interlopers to cause harm to humans. It is analogous to being on a battlefield and then having the invaders brought up short because their guns jammed and their rockets fizzled, so the lines of thought here are excellent in parsing the difficult situation to identify its weakest link. A focus on removing the virus from the planet could be a powerful and effective rallying cry to enable humanity to prevail even though they are under a very, very dark cloud at the present time.