FRIDAY, Nov. 11 (HealthDay News) -- Vaccination has greatly reduced the incidence of Haemophilus influenzae type b (Hib) among young children in the United States over the past 20 years, a new study finds.
That strain was once the most common cause of bacterial meningitis. The Hib vaccine was introduced in the mid-1980s.
But the researchers also found that other strains of H. influenzae continue to threaten the youngest and oldest people in the United States, according to the study published online Nov. 11 in the journal Clinical Infectious Diseases.
The analysis of national data showed that the highest rates of disease from non-b type strains occur in adults 65 and older and infants less than 1 year old. Among infants, most cases occur during the first month of life, with premature and low-birthweight babies the most vulnerable, according to a journal news release.
Among adults 65 and older who become ill because of H. influenzae, nearly 25 percent die, the release noted.
A disproportionately large number of both Hib and non-b type infections continue to occur among Native American and native Alaskan children, the study found. The reasons are not fully understood and should be the focus of future studies, a researcher said. Possible factors include poverty, crowded households and poor air quality.
The MedlinePlus Medical Encyclopedia has more about the Hib vaccine.
SOURCE: Clinical Infectious Diseases, news release, Nov. 9, 2011
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