Diphtheria
Diphtheria is a vaccine preventable illness that is caused by the Corynebacterium diphtheriae bacteria. Symptoms can include a fever, sore throat, and runny nose, and can resemble a common cold. The diphtheria bacteria can produce a toxin that can cause a thick white membrane, which can bleed, to form on an infected person's throat. They can also develop a "bull-neck" appearance because the glands in the neck because so enlarged.
The infection kind of sounds like strep throat on steroids, and is definitely not something you want your kids to get, especially since some of the complications include myocarditis (inflammation of the heart), airway obstruction, coma, and death. In fact, 5% to 10% of unvaccinated people with diphtheria die.
Although there are now few cases of diphtheria in the United States, before routine vaccination with the diphtheria vaccine (the D in the DTaP vaccine), which began in the 1920s, there were more than 125,000 cases and 10,000 deaths each year.
Haemophilus influenzae type b
People often confuse this bacteria infection with the flu, but it actually has nothing to do with influenza except for the fact that it was first discovered during a flu epidemic.
Haemophilus influenzae type b (Hib), before the routine use of the Hib vaccine, was the common cause of bacteria meningitis, and was a common cause of bacteremia (a blood infection), pneumonia, and endocarditis (an infection of the valves of the heart). Hib can also cause bacterial infections in other parts of the body, including cellulitis (skin infections), suppurative arthritis (joint infections), and osteomyelitis (bone infections).
Epiglottis, another infection that can be caused by the Hib bacteria, is a medical emergency that was feared by doctors and parents, as affected kids needed very quick and expert treatment for a chance to survive.
Before routine use of the Hib vaccine in 1988, about 20,000 children had Hib infections each year, including 12,000 cases of bacterial meningitis. Complications of having meningitis could be severe, affected about 30% of kids, and included deafness, seizures, blindness, and mental retardation. And about 5% of children with bacterial meningitis that was caused by the Hib bacteria died.
Measles
Measles is an extremely contagious viral infection. Before routine measles immunization began in the United States began in 1963, there were about 4 million cases of measles each year.
And unfortunately, about 20% of the children who had measles would have complications, including ear infections (10%), pneumonia (5%), and encephalitis (0.1% or 1 in 1,000). Encephalitis is an inflammation of the brain that can lead to seizures, deafness, and brain damage.
Most importantly, about 1 to 3 out of every 1,000 cases of measles results in death.
Because it is so contagious, is still such a problem in many parts of the world, and some parents still worry about the safety of the MMR vaccine and possible links to autism, health experts are on guard for a measles comeback in case immunization rates drop.
Mumps
Mumps is a form of parotitis (inflammation of the parotid gland) that is caused by the paramyxovirus. Complications can include meningitis, encephalitis, orchitis (inflammation of the ovaries or testicles), pancreatitis, and myocarditis.
Except for a mumps outbreak Iowa in 2006, mumps is now rare in the United States. The mumps vaccine was introduced in 1968 and began to be used more routinely in 1977 (it is the middle M in the MMR vaccine).
Worldwide, there were still over 400,000 cases of mumps in 2006.
Pertussis
Pertussis or whooping cough is caused by the Bordetella pertussis bacteria. Although it is now associated with causing an annoying, lingering cough in teens and adults, it is important to remember that pertussis used to be one of the leading causes of death from infections for children. In fact, before routine use of the pertussis vaccine, about 1 out of every 750 children in the United States would die from pertussis each year.
Complications of pertussis infections include seizures, pneumonia, apnea, encephalopathy (altered mental status), and up to 1% of infected infants actually die from pertussis.
Unlike most of the other vaccine preventable illnesses, there continue to be about 5,000 to 7,000 cases of pertussis each year in the United States. This is mostly because immunity from childhood pertussis vaccines (the aP in DTaP vaccine) usually wears off after 5 to 10 years, so teens and adults can get pertussis and then pass it on to newborns and infants who haven't completed their pertussis vaccines yet. A recommendation for a booster dose (Tdap) at age 12 should help combat these pertussis infections though.
