Vaccine developers quickly focused on live but weakened, or attenuated, strains of rotavirus that could be administered by mouth, without needles.
Vaccine developers quickly focused on live but weakened, or attenuated, strains of rotavirus that could be administered by mouth, without needles.
没有多久，疫苗研发人员就把目标锁定在毒性减弱但仍存活的轮状病毒品系，可用口服方式接种，而无需注射。