Haemophilus Influenzae Type b (Hib)

What is Haemophilus Influenzae (Hi) ?

Haemophilus Influenzae (Hi) is caused by a bacterial infection. There are many types or “strains” of it. The sickness can be mild or very serious.  If the infection gets into the bloodstream, brain, or other areas where it’s usually not found, it can cause severe infection.

There are several types of Hi bacteria.  Type b (known as Hib) can cause serious and life-threatening sickness like childhood pneumonia and meningitis.  Babies and children under the age of 5 are most “at risk”.

What are the symptoms?

Some strains may cause mild disease in the nose or throat, while others may cause more serious disease.

There are many strains of Hi that can cause severe sickness. Before immunization, the most common strain to cause sickness was type b.  If the Hi type b bacterium invades the bloodstream or spinal cord it can lead to health problems such as meningitis. See more about the symptoms.

How is it spread?

Hi bacteria are spread person to person. The bacteria enter the body through the nose or mouth. They can be passed through:

  • Coughs and sneezes from someone who is infected
  • Touching things that were recently exposed to an infected person’s mucous or saliva (shared utensils, cups, tissues and toys) then rubbing eyes, nose or mouth.

ls there treatment?

Serious infections of invasive haemophilus influenza are treated with antibiotics. 

What are the possible complications?

Before the introduction of Hib vaccine in 1998, Hib was the most common cause of bacterial meningitis and a leading cause of other serious invasive infections in young children. Most pediatric cases happen in children who are not vaccinated, children who are too young to start their vaccines, or those with other conditions that affect the immune system.

How do I prevent infection?

The best way to prevent Hib sickness is by getting the Hib vaccine. Getting your children vaccinated is important to reduce their risk of getting Hi type b (Hib).  If your children have not been vaccinated, they are at risk of infection.

Hib vaccine is usually given as part of a combined vaccine which provides protection against other diseases. These doses are given to infants in Ontario at multiple intervals. Hib vaccines are safe, effective and free in Ontario.

Health Care Providers

In Ontario, only invasive disease caused by H. influenzae type b is reportable to the local health unit.  Cases are reportable to the Health Unit immediately. Call 519-258-2146 ext. 1320 to speak with our infectious disease prevention department from Monday to Friday 08:30 to 4:30 p.m. and after hours to 519-973-4510.