By Rishav Chatterjee (Reuters) -Australian biotech CSL on Tuesday delayed its planned vaccine division spin-off and cut earnings forecasts due to a bigger-than-expected decline in U.S. flu vaccination rates, sending its shares down as much as 16.6%. The company told shareholders in August that it would spin off CSL Seqirus into a listed entity on the Australian Securities Exchange by next June as part of a broader restructuring plan that also involved cutting 3,000 jobs. At that time, it believed vaccin ...