Mumbai, July 24 (IANS) Megastar Amitabh Bachchan's ambassadorship for Unicef has been extended for another two years and will be working on eradicating measles and rubella infections for children. Amitabh, who is a tuberculosis and hepatitis B conqueror, has been associated with various health campaigns like polio, hepatitis B, tuberculosis and diabetes. The 74-year-old thespian on Sunday night took to Twitter and wrote: "My ambassadorship for Unicef extended for another two years after success of polio drive, now working for MR inoculation for kids." Amitabh also took to his blog to share his excitement with his fans, who he fondly calls his "extended family". "There is the Unicef... The UN Ambassadorship getting extended for another two years to work for the cause of the MR inoculation. MR not as in mister, but measles and rubella infections," he wrote.