Report of Haemophilus Influenzae serotype a intracranial infections in older children

Introduction: Haemophilus influenzae (Hi) is subdivided into typeable (a-f) and non-typeable groups. Hi serotype b (Hib) has historically been one of the important pathogens responsible for invasive infection. However, after widespread Hib vaccination, the emergence of other Hi serotypes, specifically Hi serotype a (Hia), was noted during the last few decades, mostly in children younger than 5 years of age.

Case presentation: We present two cases of severe intracranial infections with detected Hia in patients > 5 years of age within a short time frame and within the same geographic area.

Conclusion: Epidemiological studies and surveillance on Hia-related illnesses in all age groups worldwide are needed to better understand the clinical and epidemiological characteristics of Hia. This can establish a platform to develop a candidate vaccine against Hia that might protect children of all ages.