Yes definitely should take precautions where covid positive or not
You need to understand that BLACK FUNGUS did not just come out of NOWHERE
And mostly occurs in immunocompromised individuals
Due to steroid therapy /
Diabetes or any other chronic condition or drugs leading to decrease in immunity
Next Steps
Keep your surroundings clean
Wear mask where there is a lot of dust or moist and damp places
Construction sites etc
Use bouled water
Clean your nebulisers / steamers / oxygen masks and humidifiers properly