Haemophilus influenzae Invasive Disease, 2011

Seventy-one cases of invasive Haemophilus influenzae disease (1.3 per 100,000 population) were reported in 2011. Cases ranged in age from newborn to 97 years (median, 68 years). Allowing for more than one syndrome per case, 39 (55%) cases had pneumonia, 15 (21%) had bacteremia without another focus of infection, 7 (10%) had meningitis, 5 (7%) had septic shock, 3 (4%) had otitis, 2 (3%) had epiglottitis, and 1 (1%) each had septic arthritis, endometritis, and empyema. Six (8%) cases died.

Of 62 H. influenzae isolates for which typing was performed at MDH, 7 (11%) were type f, 3 (5%) type b, 3 (5%) type e, 2 (3%) type a, and 47 (76%) were untypeable.

Three cases of type b (Hib) disease occurred in 2011, compared to 1 case in 2010, 2 cases in 2009, and 5 cases in 2008. One of the Hib cases was identified in a child <1 year of age who presented with meningitis. The other Hib cases were in adults >50 years of age. One patient presented with pneumonia and the other with epiglottitis and an abscess. All 3 cases survived.

The 6 deaths occurred in patients ranging in age from 68 to 97 years. Five cases presented with pneumonia (of these, 1 also had septic shock) and 1 case presented with bacteremia without another focus of infection. All 6 cases had H. influenzae isolated from blood and all had underlying medical conditions. Of the 6 cases who died, 4 case-isolates were untypeable, 1 was serotype f, and 1 was serotype e.

• For up to date information see>> Haemophilus influenzae (invasive disease)
• Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2011