4 donors identified in the race to find rarest blood in the world and save a 2-year-old

Zainab Mughal, 2, is sick and needs a blood donor with the same rare blood she has.  A global search is underway.

(CNN)A global search is underway for blood donors matching a two-year-old with some of the rarest blood in the world.

Zainab Mughal has been battling cancer, and to survive, she's likely to need blood transfusions from seven to 10 donors. Now four have been found.
Only people of Pakistani, Indian or Iranian descent who have the same type of blood as Zainab, whose family hails from Pakistan, are likely to match with her. Less than 4% of people in those populations may match, according to OneBlood, a South Florida nonprofit organization that's aiding in a global search to identify and recruit donors for the young girl.
"We have a zero percent chance of finding compatible blood for this little girl if we look in pretty much any other ethnic group," Frieda Bright, a lab manager with OneBlood, said in a video provided by the organization. "We are searching the world to try to find blood for this little girl."
    Last month, OneBlood says they found two donors in the United States and one in the United Kingdom. A fourth donor was located in the UK on Wednesday. The search will continue worldwide until the organization finds three to six more donors, OneBlood said in a statement.