Researchers examining the density of day care centers compared to areas where cases of pertussis (whooping cough) occur did not find an association between cases and location or number of day care centers, according to research published in Public Health.
The new study, conducted by Drexel University’s Dornsife School of Public Health, looked at reported cases of pertussis in Philadelphia among children up to age six from 2001 through 2013 — which amounted to 410 — and mapped them against registered day care sites — roughly 2,000 in the city. To measure density, the team broke out the city’s neighborhoods and assessed how many day care sites there were per square mile. They then overlaid these data with the number of pertussis cases also occurring in each neighborhood.
Data in the study did not show any correlation between higher densities of day care facilities and elevated prevalence of pertussis.
“Hypothetically, more day care use could translate to more children, parents and caretakers getting sick because of everyone being in contact with each other. But we wanted to ask the question, ‘Do these people carry germs back into the local community, making other kids sick?'” said Neal D. Goldstein, PhD, assistant research professor. “The answer to that appears to be, ‘No.’ The presence of day cares in an area does not necessarily mean there is community risk of pertussis among kids.”
Eighty-one percent of children in the study who did not contract pertussis were current on their immunization against the illness. By contrast, among those who had contracted pertussis, just 64% were immunized.
“The most important factor we observed that was correlated with greater pertussis risk was lack of vaccination,” Goldstein said. “We know that vaccination is important, but this analysis suggests that it’s even more important than where you live.”
Goldstein said the lack of correlation between day cares and pertussis could come down to Pennsylvania’s strict vaccination requirements for children in day care.
“This vaccination requirement should provide a base level of protection among children — and adults — provided that people have received the vaccine,” he said. “Granted, these vaccination requirements can be exempted out of for medical and nonmedical reasons, but, hopefully, there are sufficient numbers of vaccinated children — and workers — to cancel out any affects of those who aren’t vaccinated.”