According to Catholicism, is it permitted for a priest to employ the Benedictio Deprecatoris prayer to stop the spread of the coronavirus? In our daily living, the Church has given us a treasury of prayers from everything to blessings of various object such as holy water to exorcisms against the evil spirits that possess people. There is also a blessing ad omnia, for things not having a proper blessing unto themselves.

I have been wondering through the Rituale Romanun the other day and caught myself thinking if it were liturgically permitted for a priest to pray the  following prayer in order to put an end to the coronavirus within his region (diocese or city) with the bishops consent: Benedictio Deprecatoris contra mures, locustas, bruchos, verities et alia animalia nociva (page 396). This prayer is in fact a minor exorcism.

In the Tridentine Rite a priest must have the permission of the local bishop to recite this prayer. In th Ordinary Form, I am not sure.

An English version in the Ordinary Form also exists: “Deprecatory Blessing Against Pests” that can be prayed by a priest. So when the pests won’t seem to go away, call the exterminator … and the priest.


  Here is a spiritual way to drive out pests
  
  There are times we need help from God to get rid of mice and rats, locusts, worms, rats, etc. A deprecatory prayer expresses to God –the Creator of all things– our negative or disapproval of one His guests. The prayer speaks for itself.


It seems reasonable that this prayer could be used in this circumstance, since viruses can be considered to be a life form and thus a pest.


  The origins of viruses are unclear: some may have evolved from plasmids, others from bacteria. Viruses are sometimes considered to be a life form, because they carry genetic material, reproduce and evolve through natural selection. - Viruses


Are viruses liturgically speaking considered pests (alia animalia nociva)?

My question remains thus: Is it permitted for priests to pray this particular prayer to help stop the spread of the coronavirus?
The exorcism prayer begins (Roman Ritual vol. 3 p. 164, PDF p. 1272):


  Exorcízo vos pestíferos (-as) mures (vel locustas, vel bruehos, vel vermes, vel alia animalia), per Deum ✠ Patrem omnipoténtem…I exorcize you pestiferous mice (or locusts, or grasshoppers, or worms, or any other animal), through God ✠ the Father Almighty…


The English (bottom of page here) translates this (sans the parenthetical remarks): "I cast out you noxious vermin, by God ✠ the Father almighty…"

Thus, I suppose it would be a question of whether a virus is an animal, as to whether this prayer is applicable to viruses.

The prayers from the Votive Mass for the Deliverance from Death in Time of Pestilence (a.k.a., "Mass on Occasions of Public Plague" or Missa pro vitanda mortalitate, vel tempore pestilentiæ) have been permitted to be said during the COVID-19 plague.