कारण (en. Cause)

Evidence increasingly points to an infectious cause, but debate continues on whether the cause is a conventional antigenic substance or a superantigen.

For humans, they are harmless, only cause discomfort, but the plant cause considerable harm.

There is no cause for it.

Coronaviruses can cause pneumonia (either direct viral pneumonia or secondary bacterial pneumonia) and bronchitis (either direct viral bronchitis or secondary bacterial bronchitis).

It may also cause complications during pregnancy.

Symptoms in other species vary: in chickens, they cause an upper respiratory tract disease, while in cows and pigs they cause diarrhea.

It is a cause of concern.