Four of them are from China. Work has even begun on a plant capable of producing 100 million doses a year. Sinovacs vaccine is among the three experimental COVID-19 vaccines China has been using to inoculate hundreds of thousands of people under an emergency use program. Worldwide, there are at least 10 experimental coronavirus vaccines in late-stage clinical trials, according to the World Health Organization. Pfizers vaccine, developed in partnership with Germanys BioNTech SE, is undergoing late-stage tests involving 3,100 volunteers in Sao Paulo and Bahia states.
Half of the volunteers are from the Philippines.
( z0 person :ARG0-of ( z1 volunteer ) :ARG1-of ( z2 include :ARG2 ( z3 person ) :ARG3 "1/2" ) :source ( z4 country :name ( z5 name :op "Philippines" ) ) )
(z0 / person
    :ARG0-of (z1 / volunteer-01)
    :ARG1-of (z2 / include-91
                 :ARG2 (z3 / person)
                 :ARG3 "1/2")
    :source (z4 / country
                :name (z5 / name
                          :op1 "Philippines")))
Half of the volunteers are from the Philippines .
z2 :ARG3 0
z0 :ARG1-of z2
z0 :ARG0-of z1
z2 :ARG2 z3
z0 :source z4
z4 :name z5
z5 :op1 1