The Haemophilus influenzae bacteria, also known as Hib, a highly contagious and fast-moving infection that primarily affects children under five years old, is returning, as fewer babies are vaccinated each year. The CDC reported that the percentage of babies receiving a full series of HIB type b shots from 2019 to 2021 has decreased slightly from 78.8% to 77.6% between 2019 and 2021. The decline in vaccinations and rise in cases have led to experts warning that Hib could be the next breakout preventable disease. The disease, which affects nearly 20,000 children prior to the availability of a vaccine, can cause several types of infections, ranging from mild ear infections and bronchitis to severe pneumonia, bloodstream infections, meningitis, epiglottitis, and AIDS.