Eleven per cent of the children took the antibiotic they were offered

**Most US cases of invasive Haemophilus influenzae disease are caused by
nontypeable strains**, and **no vaccine exists against nontypeable or non–type
b strains.** The Hib vaccine, which largely ended type b disease, does not
help here.

What happened

**Four invasive nontypeable Hi disease cases occurred among young children at
an elementary school in Detroit, Michigan**, in May 2023.

Three patients were hospitalised. One died.

Chemoprophylaxis — preventive antibiotics — was recommended for the patients'
household contacts, and for students and staff in the school wing where the
cases occurred.

The failure

Only 11% of students for whom chemoprophylaxis was recommended took it.

Eleven per cent. In a school where a child had just died.

Two causes are named:

• Misinformation among caregivers and health care providers
• Difficulty obtaining the chemoprophylaxis

Both halves matter and neither is about willingness. Caregivers were given
conflicting accounts — and providers were among the sources of them, which is
the harder problem. And even parents who accepted the recommendation then had
to actually obtain a prescription, which is where an outbreak response meets
pharmacy opening hours and insurance.

What it means for the next outbreak

**Nontypeable Hi can cause outbreaks among young children; therefore,
chemoprophylaxis guidance is needed.**

Guidance existed for type b and not for this. An outbreak of an organism with
no vaccine and no established prophylaxis protocol leaves a health department
improvising under time pressure.

**Achieving high chemoprophylaxis coverage requires education,
communication, and coordination with community and health care partners.**

The 11% is the measure of what happens without those three.

*Source: Weinberg MM, Akel K, Akinyemi O, et al. Invasive Nontypeable
Haemophilus influenzae Disease Outbreak at an Elementary School — Michigan,
May 2023. MMWR, Centers for Disease Control and Prevention.*