ATLANTA (AP) -- Merck & Co. is recalling about a million doses of

a childhood vaccine, after testing showed a sterilization problem

in a Pennsylvania factory.

The company is not aware of any harm to children who received

the vaccine, known as Hib, which prevents meningitis and pneumonia.

It is a three-dose shot recommended for all children under 5 and is

usually given to infants starting at two months old.

The recall involves 10 lots of Hib vaccine and two lots of a

combination vaccine for both Hib and hepatitis B, a Merck

spokeswoman said.

She said the company did not find contamination in the vaccine

itself, but in the plant where the vaccine is produced in West

Point, Pa.