Vaccination Coverage of Children in the City of Philadelphia Shelter System

Background: The City of Philadelphia Office of Supportive Housing (OSH) administers vaccinations to children entering the shelter system at city-run shelters throughout Philadelphia.  Nurses administering vaccinations in OSH shelters enter a child’s immunization records into Philadelphia Department of Public Health’s immunization information system (the KIDS registry). 

Objectives: To assess vaccine coverage rates of children aged 0-6 years who had been in the Philadelphia shelter system between July 1, 2008 and June 30, 2009, as determined by their up-to-date (UTD) status for selected vaccinations in the KIDS registry.

Methods: Children listed in OSH records during the assessment period who were aged 0-6 years as of June 30, 2009 were matched against records from the KIDS registry to assess their age-specific UTD status for three indicator vaccines:  DTaP (diphtheria, tetanus, acellular pertussis), IPV (polio), and MMR (measles, mumps, rubella). 

Results: Of the 2,014 children in OSH records during the assessment period, 1,864 (93%) were successfully matched in the KIDS registry. Of these matched records, 1,181 (81%) were UTD for their age-specific immunizations for the indicator vaccines (DTaP, IPV, MMR) by six years of age.  Subgroup analyses indicate that 5-6 month olds are furthest behind on their immunizations, with only 59% age-appropriately immunized when they reach seven months of age.  A substantial improvement is seen in the 7-15 month age group, with 79% of children UTD with their immunizations.

Conclusions:Children aged 0-6 years that have been in the Philadelphia shelter system are receiving their age-appropriate vaccines according to the ACIP schedule.  Efforts by the City of Philadelphia Office of Supportive Housing to immunize children upon entry into the shelter system are contributing to improving immunization coverage rates in Philadelphia children.  Additional efforts should target infants in the first six months of life to achieve improved coverage rates.