World Health Organization, maternal vaccination, antibody therapy, prevent respiratory syncytial virus (RSV), infants, recommendations, shot, third trimester, pregnancy, Pfizer, United States, Canada, drugmaker, babies, strategic advisory group, immunization, maternal vaccine, single shot, drugmaker Pfizer, approval, protect, WHO, concerns, supply, high cost, global access, equity, treatment, RSV, cold-like symptoms, pneumonia, toddlers, older adults. Más