But the vaccine reliably protected only children 2 years of age and older.

In theory, such a strategy can work because the vaccine, if given within four days of exposure to the virus, protects people from the disease.

How long does the vaccine protect a person from smallpox?

A vaccine can protect your child against the virus.

The vaccine will not protect against other types of influenza.

This vaccine, used since 1921, can protect children from severe forms of tuberculosis.

The vaccine can fully protect people if given within four days of exposure to the virus.

Another question is how long the vaccine will protect against chicken pox.

This year, as usual, the vaccine protects against three strains.

Eventually, it might be possible to combine the vaccines to protect people from both diseases with a single shot.