All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
Allah the Almighty has asked the people to supplicate to Him in all times particularly in times of hardship. This is based on believing in Divine Decree, that Allah runs this universe, and that nothing turns back Decree except supplication. The evidence on this is that 'Salman narrated that the Messenger of Allah (s.a.w) said: "Nothing turns back the Decree except supplication, and nothing increases the life-span except righteousness." {Related by Tirmithi}.
It was mentioned in the Prophetic Sunnah that the believers used to offer Dua` Qunoot in prayers in times of calamity. This is attested to in the following narration: Abu Salama b. Abd al-Rahman b. 'Auf heard Abu Huraira say: (When) Allah's Messenger (PBUH) (wished to invoke curse or blessing on someone, he would do so at the end) of the recitation in the dawn prayer, when he had pronounced Allah-o-Akbar (for bending) and then lifted his head (saying):" Allah listened to him who praised Him; our Lord! to Thee is all praise" ; he would then stand up and say:" Rescue al-Walid b. Walid, Salama b. Hisham, and 'Ayyash b. Abd Rabi'a, and the helpless among the Muslims. O Allah! trample severely Mudar and cause them a famine (which broke out at the time) of Joseph. O Allah! curse Lihyan, Ri'l, Dhakwan, 'Usayya, for they disobeyed Allah and His Messenger." (The narrator then adds): The news reached us that he abandoned (this) when this verse was revealed:" Thou but no concern in the matter whether He turns to them (mercifully) or chastises them; surely they are wrongdoers" (ill. 127)" {Related by Muslim}.
In light of the spread of COVID-19, people are encouraged to offer Dua` Qunoot when performing obligatory congregational prayers or praying alone. They ask Allah to remove this pandemic and protect them from its harms. This is the view of many Imams and was stated by Imam Shafie who said: "It is encouraged to offer Dua` Qunoot only in the Fajir prayer unless there is a calamity, in which case the Imam (Person leading people in prayer) is allowed to perform this Dua` in all prayers if he wants to." {Al-Umm, V.1: P.236}. Moreover, Imam Al-Shafie said that it isn`t recommended to offer Dua` Qunoot in the prayer of the two Eids or that of Istisqaa`.
This Dua` should be offered silently for the person praying alone and loudly for the Imam, even in silent prayers, and the prayer performs should respond by saying "Amen" loudly. "In all prayers, including the silent ones, the Imam offers Dua` Qunoot loudly following the example of the Prophet (PBUH), as reported by Abu Hurairah. However, his voice should be lower than that when reciting Quran and the praying people should respond by saying "Ameen"." {Asna Al-Matalib, V.1:P.159}.
In addition, it is permissible for a Muslim to ask Allah whatever he wants in this Dua`, however, it isn`t recommended to prolong it. "According to the correct opinion of the Shafie scholars, it isn`t conditioned to make a specific supplication. Rather, it is permissible to ask Allah for anything. Further, it is recommended to send prayers and blessings on the Prophet (PBUH) and his family at the beginning as well as the end of this Dua`." {Shareh An-Nawawi Ala Muslim, V.5:P.176}.
In conclusion, it is recommended to offer Dua` Qunoot in times of calamity and it is confirmed in the Prophetic Sunnah that the Prophet (PBUH) has done so. This is also the opinion of the majority of the Muslim scholars. Moreover, Dua` Qunoot is recommended in congregational prayers, silent or loud, and when praying alone. We pray that Allah protects us from all evils and calamities. And Allah the Almighty knows best.