U.S. health officials asked doctors on Thursday to be alert for possible cases of meningitis and other illnesses in children caused by Hib bacteria amid an ongoing vaccine shortage.
Officials are most concerned about bacterial meningitis and sepsis, a bloodstream infection, caused by Hib (Haemophilus influenzae type b) in children under age 5 because of the high risk of death or serious complications, Centers for Disease Control and Prevention epidemiologist Mike Jackson said.
Meningitis is the inflammation of the tissue surrounding the brain and spinal cord, and can be caused by viral or bacterial infections. Before the vaccines, Hib was the most common cause of bacterial meningitis.
Merck & Co Inc last year recalled its Hib vaccines because production equipment may not have been properly sterilized. Merck initially said the PedvaxHIB and COMVAX vaccines would return to the U.S. market late this year, but in October said they would not do so until mid-2009.
Hib vaccine made by Sanofi Pasteur, the vaccines division of Sanofi-Aventis, remains available. But because of the absence of the Merck vaccines, the CDC has asked doctors to postpone the routine Hib vaccine booster doses typically given at age 12- to 15 months until the vaccine supply improves.
Because of the Sanofi supply, Jackson said there is enough vaccine to give children the primary vaccine series -- doses at 2, 4 and 6 months of age -- but not the booster doses.
With the vaccine shortage, children who otherwise might be fully protected against Hib could be vulnerable. Jackson said the CDC wants doctors to notify local health departments if they come across cases of Hib disease in children and get a clinical specimen for confirmation of the illness.