We present two cases of bacterial meningitis caused by Haemophilus influenzae type b (Hib) which developed a few days after conjugate Hib vaccination. This phenomenon of postimmunization provocative time period is reviewed and discussed. These cases serve as a reminder to clinicians of the risk, albeit rare, of invasive Hib disease in the short period after successful immunization.

Globally, Haemophilus influenzae type b (Hib) is one of the leading causes of childhood meningitis and pneumonia. Vaccines against Hib have been developed and introduced into routine immunization programs in most industrialized nations, in which the burden of Hib disease has been clearly demonstrated. In Asia, the burden of Hib disease has been perceived as relatively low compared with other pa...

BACKGROUND Oropharyngeal carriage studies of Haemophilus influenzae type b (Hib) and the rapid drop in Hib invasive disease in countries with widespread Hib conjugate vaccine immunization programmes for infants have indicated there may be significant indirect effects (herd immunity) associated with these vaccines. Our goal was to quantify the magnitude of these effects in an American Indian pop...

OBJECTIVE To identify reservoirs of Haemophilus influenzae type b (Hib) pharyngeal carriage and assess barriers to vaccination among 2 Amish communities in Pennsylvania. METHODS We investigated recent cases, performed community surveys for Hib vaccination coverage and pharyngeal carriage, and administered a questionnaire assessing vaccination knowledge and attitudes to 298 members of 2 Amish ...

OBJECTIVE To describe invasive Haemophilus influenzae type b (Hib) infections in individuals aged 15 years or older in England and Wales between 1991 and 2003. DESIGN Prospective, laboratory based surveillance of invasive Hib infections and cross sectional seroprevalence study. SETTING England and Wales. PARTICIPANTS Cases were confirmed by isolation of H influenzae from a normally steril...

BACKGROUND The Gambia was the first country in Africa to introduce conjugate Haemophilus influenzae type b (Hib) vaccine, which, as in other developing countries but unlike industrialized countries, is delivered as a 3-dose primary series with no booster. This study assessed its effectiveness 14 years after introduction. METHODS Using methods standardized during >20 years in the study site, c...

In 2008, five children aged <5 years were reported to the Minnesota Department of Health (MDH) with invasive Haemophilus influenzae type b (Hib) disease; one died. Only one of the children had completed the primary Hib immunization series; three had received no doses of Hib-containing vaccine. The five Hib cases are the largest number among children aged <5 years reported from Minnesota since 1...

Haemophilus influenzae (Hi) is an important bacterial pathogen in children, causing a variety of respiratory infections and lifethreatening diseases such as meningitis, epiglottitis, pneumonia and septicaemia. Occasionally, Hi can also cause sporadic infections such as septic arthritis (SA). Before the advent of Hi type b (Hib) vaccination, paediatric invasive Hi disease was caused mostly by Hi...

In response to the 2007-2009 Haemophilus influenzae type b (Hib) vaccine shortage in the United States, we developed a flexible model of Hib transmission and disease for optimizing Hib vaccine programs in diverse populations and situations. The model classifies population members by age, colonization/disease status, and antibody levels, with movement across categories defined by differential eq...

The validity of the commonly held view that Haemophilus influenzae type b (Hib) diseases are rare in Asia is challenged in this article by a thorough analysis of the data available, often in languages other than English. The entire spectrum of Hib disease, not only meningitis, was taken into account, and over 100 reports from 25 countries were explored. Hib was the leading agent among nontuberc...