A new study shows that infants who received the pneumococcal conjugate vaccine (PCV) following the combination vaccine for diphtheria, polio, tetanus, pertussis, and Haemophilus influenzae type b (DPTaP-Hib vaccine) appear to experience less pain than those who receive the injections in the reverse order.
Researchers say it’s the first study to look at whether the order of infant immunizations affects the pain children experience. The results suggest that varying the order of vaccine administration is a simple, effective, and cost-free way to minimize pain.
"Multiple injections are routinely administered during a single visit to a physician," write researcher Moshe Ipp, MBBCh, of The Hospital for Sick Children in Toronto and colleagues in the Archives of Pediatrics and Adolescent Medicine. “Because some vaccines cause more pain than others, the order in which they are given may affect the overall pain experience."
Immunization Order Affects Pain
In the study, 60 healthy infants 2-6 months old were given the combination vaccine first, and another 60 were given the pneumococcal conjugate vaccine first.
To measure the pain the infants experienced, researchers videotaped the procedure and assessed the pain on a scale that considered the baby’s facial expression, body movements, and crying after vaccination. Parents were also asked to rate their child’s pain level on a scale of zero to 10.
The study showed that the infants given the less painful combination vaccine first followed by the more painful PCV vaccine experienced less pain on average overall. Pain increased from the first injection to the second, regardless of which vaccination came first.
Researchers say the results suggest that when two infant immunizations are given, the least painful should be given first. Giving the more painful injection first may focus the infant’s attention on the procedure and activate pain processing centers in the brain, intensifying the response to anything further.