Haemophilus Influenza Type B (HIB) Disease & Vaccine Information

Find the Information You Need to Make Informed Vaccine Decisions

HIB: The Disease

Haemophilus influenzae (H. influenzae) is a small gram-negative coccobacillus found only in humans and can be either encapsulated (typeable) or unencapsulated (nontypeable). H. influenzae type b (Hib) is transmitted by direct contact with respiratory secretions and enters the body through the upper respiratory tract. In most cases, Hib can remain in the mouth and nose for up to several months, without causing illness. In general, H. influenzae disease is considered to be minimally contagious, however, if a person has close contact to someone who is infected with or is carrying H. influenzae, transmission can occur. Learn more about Hib…

HIB Vaccine

Currently, there are four Haemophilus influenzae type b vaccines available for use by the United States Food and Drug Administration (FDA) and recommended by the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control (CDC). The CDC’s Advisory Committee on Immunization Practices (ACIP) has approved Hib vaccine for use in children at 2, 4, 6 and 12-15 months of age. The ACIP, however, has not made any recommendations regarding the use of the newly FDA approved 6 in 1 (hexavalent) vaccine, VAXELIS, at this time. Learn more about HIB vaccine…

HIB Quick Facts

Haemophilus Influenzae Type B (Hib)

Haemophilus influenzae type b (Hib) is a bacterial infection that can cause severe illnesses in children, including meningitis, epiglottitis, pneumonia, arthritis, and cellulitis;
In general, the transmission of Hib is considered to be limited and when it occurs, it usually affects only close contacts such as household members. Prior to the introduction of the Hib vaccine, most children acquired natural immunity to Hib by the time they were 5 or 6 years old. Continue reading quick facts…

HIB Vaccine

All infants and children who participated in Hib vaccine pre-licensing clinical trials also received other vaccines in addition to the Hib vaccine. As a result, it is not possible to determine the specific adverse reaction to monitor for following Hib vaccination. The administration of multiple vaccines also makes it difficult to determine the specific vaccine that might have triggered the reactions reported in both clinical studies and to VAERS.
Using the MedAlerts search engine, as of February 28, 2023, there have been more than 90,289 reports of Hib vaccine reactions, hospitalizations, injuries and deaths following Hib vaccinations made to the federal Vaccine Adverse Events Reporting System (VAERS), including 2,875 related deaths, 18,460 hospitalizations, and 1,812 related disabilities. Nearly 85 percent of HIB vaccine-related adverse events occurred in children three years old and under. Of these Hib-vaccine related deaths reported to VAERS, over 92 percent of the deaths occurred in children under three years of age. Of these reported deaths, 2,143 occurred in infants under the age of 6 months.
As of March 1, 2023 , there had been 175 claims filed in the federal Vaccine Injury Compensation Program (VICP) for injuries and deaths following HIB vaccination, including 33 deaths and 142 serious injuries. Continue reading quick facts...

NVIC encourages you to become fully informed about Haemophilus Influenza Type B (Hib) and the Hib vaccine by reading all sections in the Table of Contents , which contain many links and resources such as the manufacturer product information inserts, and to speak with one or more trusted health care professionals before making a vaccination decision for yourself or your child. This information is for educational purposes only and is not intended as medical advice.