Even in the face of outbreak of a disease parents are often found lacking in getting their kids vaccinated indicated a study. 'We have always assumed that when the risk of catching a disease is high people will accept a vaccine that is effective in preventing that disease. Our results may challenge this assumption' said Elizabeth Wolf of University of Washington in the US. For the study researchers compared rates of infant vaccination with the diphtheria tetanus and pertussis vaccine (DTaP) before and during an epidemic of pertussis (whooping cough) in Washington state. They found no difference in vaccination rates.