Question

An influenza virus strain was discovered in birds in two smallSouth East Asian islands twenty years ago. It killed hundreds ofpeople in and around this island before scientists developedspecific antibodies to this strain. Since then, two slightlyvariant strains of this influenza virus have been found in in thesame bird population in these islands in the last year, which wereresistant to the old antibodies and resulted in killing hundreds ofpeople.

1)Why does the influenza virus evolveinto different strains much more rapidly than the DNAviruses?

2)One way to reduce the infection by the influenza virusis to use antibodies raised against the specific influenza strain.What type of viral molecules/ structures do the medicalimmunologists target for developing specific antibodies?

3)How do these viruses enter human cells?

4)Why some birds are resistant to the various influenzavirus strains?

Any thoughts would be very appreciated.

Edit: No response will be rewarded points.

(I needed some feedback earlier).

Thank you.