Clinical Course and Outcomes of Invasive Haemophilus influenzae Infections among Children at Two Hospitals in Alaska

Area of Science:

• Pediatric Infectious Diseases
• Bacterial Pathogenesis
• Public Health Epidemiology

Background:

• Invasive Haemophilus influenzae infections pose a significant threat to child health, particularly in vulnerable populations.
• Understanding the specific types and clinical manifestations of H. influenzae is crucial for effective disease management and prevention.

Purpose of the Study:

• To compare the clinical course and outcomes of invasive Haemophilus influenzae disease across different serotypes in children in Alaska.
• To identify specific H. influenzae types associated with severe complications and mortality.

Main Methods:

• Retrospective review of invasive H. influenzae cases in children under 10 years old treated at two Alaskan hospitals between 2013-2019.
• Data collection included clinical and demographic information; categorical variables were analyzed using Fisher's exact test.

Main Results:

• Sixty-two invasive H. influenzae infections were identified: 45 type a (Hia), 8 type b (Hib), 7 nontypeable (NTHi), and 2 type f (Hif).
• All cases occurred in Alaska Native children; 69% were previously healthy. 31% required intensive care, and 21% experienced death or sequelae.
• Deaths and long-term sequelae were linked to Hia or Hib meningitis. NTHi infections were more frequently associated with respiratory support needs (86% vs. 27%).

Conclusions:

• Invasive H. influenzae infections, including Hia, Hib, Hif, and NTHi, result in severe illness among Alaska Native children.
• Haemophilus influenzae type b and type a are associated with higher fatality rates due to meningitis, while NTHi causes more respiratory complications.
• Tracking invasive H. influenzae trends is vital for informing public health strategies and guiding the development of new vaccines.