Which of the following lead to an outbreak of Influenza in China in 2013 -: (A) H
1
N
1, (B) H
3
N
2, (C) H
2
N
2, (D) H
7
N
9
Answer is D. In china, there was an outbreak of influenza caused by Avian influenza H7N9, in 2013.
It started in china and spread to Hong Kong.
Most common age group affected was older male (> 50 years).