Pediatric Oncall - Vaccination [ DPT/DT/TT VACCINE ]

DPT/DT/TT VACCINE

What is DPT/DT/TT given for?
DPT is a combination vaccine to protect against Diphtheria, Tetanus & Pertussis (whooping cough). DT protects against diphtheria and Tetanus and TT protects against tetanus.

When is DPT given?
3 primary doses of DPT vaccine are given at 4 weeks interval starting at 6-8 weeks of age along with the 3 primary doses of oral polio vaccine. It is recommended routinely for each and every child.

When are boosters of DPT given?
First booster dose of DPT is given at the age of 15-18 months along with the 1st booster dose of OPV. Govt. of India under EPI recommends only DT as the second booster at the age of 4-6 years whereas Indian Academy of Pediatrics recommends DPT and OPV as the 2nd booster at 4-6 years of age.

Why do the recommendations differ from authority to authority regarding 2nd booster dose?
Indian Academy of Pediatrics feels that the immunity against pertussis & poliomyelitis will wear off by 5 years as will happen for diphtheria & tetanus. This will lead to increased risk of whooping cough & poliomyelitis in adolescents & adults. Hence IAP recommends OPV & DPT & not only DT as the 2nd booster at 4-6 years.

How is DPT given?
DPT is given as intramuscular injection.

What is the efficacy of DPT vaccine?
Efficacy of diphtheria toxoid & tetanus toxoid is excellent. The protection is seen in nearly 100% of vaccinees with good long-term protection after primary & booster doses of DPT. The pertussis component is a weak candidate & the protective efficacy is seen in 70-90% of cases.

What are the side effects of DPT/DT/TT?
Local side effects: It includes pain, swelling, redness & difficulty in walking. It is seen in 30-40% of vaccinees. It persists for 24-72 hours & responds to paracetamol. Sometimes a nodule forms at the injection site, which may persist for several days to weeks. It may soften and form a sterile abscess. It does not merit any treatment except analgesics. If it shows fluctuation, it can be drained.

Systemic side effects: It includes fever, lassitude, anorexia, vomiting, irritability, excessive crying etc. seen in 30 – 40 % of patients. Fever is usually mild to moderate, lasts for 2-3 days & responds to paracetamol

Sometimes, Pertussis component of DPT is responsible for fever more than 1050 F, excessive crying & screaming spells lasting for more than 4 hours and convulsions. If a patient develops any of those adverse reactions it is a contraindication to further use of DPT & instead only DT should be used. Such reactions should be immediately reported to doctor.

What is the treatment of side effects following DPT?
Paracetamol or ibuprofen can be used to treat pain, swelling, redness, difficulty in walking and fever. It takes 2-3 days for the symptoms to disappear. In case abscess has formed, treat with antibiotics and drainage. Persistent nodule should be left alone, as it does not lead to any other symptoms.

Can DPT be given along with other vaccines?
DPT can be given along with any other vaccines. In fact it is given along with OPV, Hepatitis B & Hib vaccine. A combination vaccine containing DPT + Hib and DPT + Hepatitis B are available

What is acellular pertussis DPT vaccine?
As seen before, the severe adverse side effects seen with DPT are due to pertussis component. It was realized that the reactions were due to components of cell wall of pertussis organism, which are not required for efficacy of vaccine. An acellular pertussis vaccine that does not have whole cell wall of pertussis has been developed that can be routinely used for immunization.

When is DT used?
It is used in patients where pertussis component is contraindicated and as 2nd booster as per EPI schedule.

What is dT vaccine?
dT vaccine has 1/10th dose of diphtheria toxoid than present in DT/DPT. If full dose of diphtheria toxoid is given as present in DT/ DPT in children above 10 years of age, it can lead to serious side effects like heart toxicity, serum sickness like reactions etc. With lack of natural boosting due to mass vaccination, diphtheria can occur beyond 10-15 years of age in vaccinees. One needs to give booster of diphtheria at 10 years and maybe every 10 years thereafter to maintain protective titres. dT is useful in such cases as a booster at 10 years (instead of TT).

When is TT routinely used in children?
TT is routinely used for children >10 years of age as they do not need both Diphtheria & pertussis components. It is given as a booster dose at 10 years & 16 years to children who have received their primary doses/boosters of DPT/DT before. It can be then taken every 5-10 years to maintain protection life long

When is TT given to pregnant women?
A lady who is previously unimmunised should receive 3 doses of TT during pregnancy at 1-month interval starting the first dose at 28 weeks. The last dose should be at least 30 days prior to the expected date of delivery so that there is enough time for good antibody titres to develop in mother & for it to be passed on to the fetus to prevent tetanus in newborn. During repeat pregnancy, 2 doses of TT are given at 4 weeks interval. Again the last dose is given at least 30 days before delivery.

When is TT given to an adult with injury?
An adult who has never received or has received incomplete course of TT before in life should be given 3 doses of TT at 4 weeks interval followed by a booster after 1 year & then every 5 years. If he then develops any injury or requires any surgery there is no need to take anymore TT as he is protected in between the doses. If such an adult has taken the last TT beyond 4-5 years in past, he can be given one dose of TT, which acts as a booster. It is neither required nor desirable or safe to give TT for each and every injury every now & then in such a protected person.

What if the child gets injured, should he receive TT?
A child who has received 3 primary doses of DPT/DT is protected till 15 months of age & does not need TT. If he is 15-18 months of age he should receive his first 1st booster of OPV + DPT which will also boost up anti-tetanus immunity. Such a child is protected till 4 years & does not need a TT till that age. If he is between 4-6 years he should receive his 2nd booster of DT or OPV + DPT which will boost up his anti-tetanus immunity too. Such a child is now protected till 10 years of age. After this a booster of TT is given at 10years, 16 years & every 5 years thereafter. In between such doses there is no need to give TT for injury.

What harm is done if one gives TT frequently?
If TT is given frequently, it will hyper-immunize the patient. Such a patient can develop arthus like phenomenon with development of fever, rash, joint pain, joint swelling etc. Hence it is not desirable to give frequent injections of TT in an otherwise immunized patient.

Should a patient who recovers from diphtheria or tetanus or pertussis receive vaccine against the respective disease?
Neither diphtheria, tetanus or pertussis disease leads to strong immunity. Hence, a person who has recovered from such diseases should receive 3 primary doses and boosters of DPT/DT/TT as appropriate for his age.

Last updated on 02-12-2003