बेफोर भाइरासफोरा दिदोमै सोलायनाय, दिहुननाय, जायफोरखौ खाव-बाहागोफोर एबा फोलेरफोर बुङो, बेफोरो थार भाइरासनिफ्राय जुदा नाथाय बेनि आखुथायफोरनि माखासे थायो।
These viruses are constantly changing, producing what are called subtypes or strains that are different from the original virus but retain some of its characteristics.