<prompt> Yellow fever vaccination becomes effective after how many days of vaccination:5 days10 days10 weeks10 months  <response>: Ans. b 10 daysRef : K. Park 23rd ed. 121, 283 Yellow fever vaccine certificate becomes valid after 10 days of vaccination. Duration of yellow fever vaccination coverage: 10 days- 10 years. Quarantine period of yellow fever: 6 days maximum I.P of YF 