Diptheria – Tetanus – Pertussis (DTaP, DT, Td, Tdap, DTP)

Diphtheria, once known as ‘The strangling angel of childhood’ is a severe infection of the throat and nose that can actually block the airway and cause suffocation. It can also cause paralysis and heart failure. While it was never extremely common, it was quite deadly. Diphtheria has almost disappeared since the introduction of vaccines against it, but still persists in parts of the world where vaccination is not given.

Tetanus is another lethal illness. It is caused by a germ that lives in dirt. When it gets in a cut or open wound it releases poisons which result in severe muscle spasms, “lockjaw”, and often death. Tetanus continues to occur at a stable low rate in the United States, mostly in adults who have let themselves go more than 10 years without a “booster”, and then get a dirty cut. Because the germ survives well in dirt without infecting anybody, we will never be able to eradicate this disease. Nevertheless, the U.S. boasts one of the lowest Tetanus rates of any nation in the world.

Pertussis, or “Whooping Cough”, used to cause severe pneumonia with a prolonged cough, vomiting, and difficulty breathing. In addition to pneumonia it can cause seizures, brain damage, mental retardation, and death. Before immunization there used to be 150,000 to 260,000 cases of, and up to 9000 deaths from, Pertussis yearly in the US. Pertussis remains common despite immunization against it! Between 90 and 300 cases are reported every year in Massachusetts alone, and it’s estimated that as many as 10-times that number happen but are either not diagnosed or not reported. However, deaths from Pertussis today are rare.

The reason so much Pertussis persists is that vaccine induced immunity to it is temporary, lasting only 3-6 years. Teenagers and adults can get it even though they were immunized as children. When an older child or adult gets Pertussis it is MILD – looking like a persistent hacking cough that “hangs on” for a long time. They might not even go to the doctor, and if they did the doctor might not think there is much wrong! However, when an infant gets Pertussis it is a serious matter. Babies with Whooping Cough have spells of coughing so bad that they may not be able to eat, drink, or breathe! They may get a bad pneumonia, and the lack of oxygen from either this or the coughing spells can cause brain damage! Some babies with Whooping Cough will have swelling of the brain and seizures, which can also cause permanent brain damage. They may go into shock from dehydration, and they may even die. All of these dangerous Whooping Cough symptoms become less severe and less likely the older a child gets. Most infants less than 6 months old who get whooping cough will need to be hospitalized, while few over 2 years will need to be. Almost all severe cases of Whooping Cough we see nowadays occur in un-immunized infants, either because they are too young to have received the first vaccine dose yet or because it was withheld for some reason. The source of the infection can usually be traced to a parent, older sibling, or other relative who “just thought they had a cold”.

We use combinations of all three (DTP) vaccines. No one has ever disputed the need for or safety of the Diphtheria and Tetanus portions of these vaccines. We know that they cause very few and only very mild side effects – most commonly redness and soreness at the injection site. Fever is very rare, and more serious risks are unheard of.

The Pertussis portion of DTP used to be the focus of much controversy, and was actually the main motivation for the National Childhood Vaccine Injury Act in the first place. It was one of our oldest and “crudest” vaccines – consisting of whole Pertussis germ cells which had been simply killed and washed. Perhaps because of this, it had a very high side effect rate.

Luckily, we no longer have to worry about the risks of “whole cell” Pertussis vaccine. ACELLULAR Pertussis vaccine (which, combined with Diptheria and Tetanus, is referred to as “DTaP”) is made with a more modern process using purified germ proteins rather than whole cells. DTaP’s side effect rate is almost zero, and there have been no reported cases of seizures, convulsions, or shock in association with it. It even provides somewhat better immunity than the old vaccine did against Whooping Cough!

Until recently teenagers and adults were NOT routinely immunized against Pertussis. The “Td” vaccine for adults and children over age 7y was originally developed without a “P” component because the side effects of the whole-cell Pertussis vaccine were even worse in those ages than they were in younger children. The acellular Pertussis vaccine was not tested in teenagers and adults when it was originally developed. The immunity against Pertussis provided by the early childhood doses of DTP or DTaP “waned” or wore off after 5-10 years, and so most teenagers and adults are not immune to this disease. Luckily the disease is not as severe in these age groups as it is in infant -producing only a “bronchitis” that can last for 6-12 weeks – but nonetheless adults and teenagers represent the reservoir of disease from whence infants can catch it. Our only hope of ever eradicating Pertussis really lies in immunizing teenagers and adults, as well as children. In the late 1990’s research to test the acellular Pertussis vaccine in teenagers and adults finally began, and it has now found to be safe, effective, and just as side-effect free in this age group as it is in children. The result is “Boostrix”– combining Tetanus, Diptheria, and acellular Pertussis vaccines in doses appropriate for teens and adults (Tdap). We give Tdap routinely at the 12 year visit.

For more information, please visit Centers for Disease Control and Prevention (CDC) website at:

DTap: http://www.immunize.org/vis/dtap01.pdf

Td &Tdap:: http://www.immunize.org/vis/td_tdap.pdf