Childhood vaccine coverage misses target

The Centers for Disease Control and Prevention (CDC) says that when it comes to measles, mumps, and rubella (MMR) and varicella vaccination of children entering kindergarten, coverage is still not quite where it needs to be to reach the Healthy People 2020 goal of coverage of 95% of children or more.

According to CDC’s report, based on data from annual school vaccination assessment reports, the MMR vaccination rate was 94.8% in 47 states and the District of Columbia for children entering school in 2011. Median coverage rates ranged from 86.8% in Colorado to 99.3% in Texas.

Median coverage with 2 doses of varicella vaccine among 33 reporting areas was 93.2%, ranging from 84% in Colorado to 99.2% in Mississippi and Texas.

Median coverage rates for vaccines for diphtheria, tetanus toxoid, acellular pertussis, poliovirus, and hepatitis B virus all were at or above the target of 95%.

Exemption rates in 49 reporting states and the District of Columbia ranged from a low of less than 0.1% in Mississippi to a high of 7% in Alaska, meaning that more than 4 million children entering US kindergartens in 2011 were unvaccinated because of exemptions for medical, religious, or philosophic reasons. The median total exemption level of 1.5% represents a median increase of 0.2 percentage points compared with the 2009-2010 school year. The largest increase in exemptions of 3.4 percentage points occurred in Arkansas. The largest decrease, 2.3 percentage points, occurred in Nebraska.

According to the report, the high number of measles cases in Europe in 2011 contributed to record numbers of cases being imported to the United States. Most US cases occurred in people who were not vaccinated for nonmedical reasons. Because exemptions tend to cluster geographically, areas with low immunization coverage can foster ongoing transmission after importation.

The CDC says that although coverage is at or close to target levels, extremely transmissible diseases such as measles remain a health threat, and as long as they do, monitoring continues to be critical.

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