The vaccine does not contain any whole bacteria (alive or dead).
After 1990, two more vaccines containing it were added to the required list for all infants.
Some vaccines contain only a part of the disease germ.
The old, trivalent vaccine also contains strains against Types 2 and 3.
"Who wants to sit down and say to parents, 'We're giving your babies vaccines containing mercury'?"
The vaccine contains two virus types blamed for most cases of the lesions.
The vaccine does not contain any infectious material from the influenza virus.
Women found to be susceptible are not vaccinated until after the baby is born because the vaccine contains live virus.
Since the 1930s some vaccines have contained the preservative thiomersal.
The vaccine contains the three strains of viruses that are most likely to be circulating this winter.