The graph shows all reactions occurring within a week of the vaccine, so it is most unlikely that all the problems were caused by the vaccines in all the children. However, these are the only details of reactions that the study - sponsored by the manufacturer of the vaccine - provides. It is clear that side-effects were frequent. However, less common, but possibly serious, reactions could easily have been missed because of the small numbers of children involved. [1]
[1] Kitchin N et al. A randomised controlled study of the reactogenicity of an acellular pertussis-containing pentavalent infant vaccine compared to a quadrivalent whole cell pertussis-containing vaccine and oral poliomyelitis vaccine, when given concurrently with meningococcal group C conjugate vaccine to healthy UK infants at 2, 3 and 4 months of age. Vaccine 2006; 24: 3964-3970.
Common side-effects after Pediacel
(the 5-in-1 vaccine)