Namo Narayanaya
Thank you for such noble thoughts to pray for all humanity in admist of horrendous situation. Well first is to save yourself and your family by staying in house and encouraging others to stay in house as much as they can. That’s the practical first thing to do.
Mantras to be changed for protection –
“Narayana Kavacha” by Bhakta Prahalada in Brahmanda/ other Puranam
Sudarshana astakam/ Strotha by Swami Vedanta Desikan
“Devi Kavacha” from Markendeyaya Puranam – HIGHLY RECOMMENDED
“Hanuman Chalisa” by Bhakta Tulsidasa
You can also search some verses from “ATHARVA VEDA” but pronunciation should be right.
To be honest, sincere prayers to your deity is what needed. please pray for wellbeing of good ppl. It’s a tough time.
Good wins ultimately.
Happy Hanuman Jayanti
Jai ShriRama