ABSTRACT
INTRODUCTION Protein-conjugated Haemophilus influenzae type b (Hib) vaccines represent a scientific and technological triumph over one of the most widespread and pernicious infant diseases of the 20th century. The public health triumph, however, lags further behind. Each year Hib causes approximately 3 million cases of meningitis and severe pneumonia worldwide leading to 386,000 deaths in children aged less than five years (1). Of those who survive meningitis, 30% to 40% go on to develop lifelong disabilities such as mental retardation or hearing loss (1). Conjugation of Hib polysaccharide to immunogenic proteins overcomes the innate deficiencies of young infants in recognizing repeating carbohydrate antigens, and this discovery has led to the development of commercial vaccines that have almost eliminated Hib disease from the industrialized world.
