August was National Immunization Awareness Month. For most pediatricians, it is also a very busy month as patients prepare for the start of the new school year. So how are we doing?
On August 28, 2013, vaccination coverage of U.S. children aged 19-35 months was published in Morbidity and Mortality Weekly Review (2014; 63:741-8) based on results from the National Information Survey (NIS), which provides national, regional, state, and selected local area vaccination coverage estimates. NIS has monitored vaccination coverage since 1994 for all 50 states and assists in tracking the progress of achieving our national goals. It also can identify problem areas that may require special interventions. Survey data was obtained by a random telephone survey using both landline and cellular phones to households that have children born between January 2010 and May 2012. The verbal interview was followed by a survey mailed to the vaccine provider to confirm the verbal vaccine history.
Highlights
Vaccination coverage of at least 90 %, a goal of Healthy People 2020, was achieved for receipt of one or more dose of MMR (91.9%); three or more doses of hepatitis B vaccine (HepB) (90.8 %); three or more doses of poliovirus vaccine (92.7%) and one or more doses of varicella vaccine (91.2%).
Coverage for the following vaccines failed to meet this goal: four or more doses of diphtheria, tetanus, and pertussis vaccine (DTaP) (83.1%); four or more doses of pneumococcal conjugate vaccine (PCV) (82%); and a full series of Haemophilus influenzae type b (Hib) (82%). Coverage for the remaining vaccines also fell short of their respective targeted goals: two or more doses of hepatitis A vaccine (54.7%; target 85%); rotavirus (72.6%; target 80%); and hepatitis B birth dose (74.2%; target 85%).
Compared with 2012, coverage remained stable for the four vaccines that achieved at least 90% coverage. For those that did not, rotavirus was the only vaccine in 2013 that had an increase (4%) in coverage. Of note, there was an increase in the birth dose of 2.6% for Hep B.
Children living at or below the poverty level had lower vaccination coverage, compared with those living at or above this level for several vaccines, including four or more doses of DTaP; full series of Hib vaccine, four or more doses of PCV, and rotavirus vaccine. Coverage was between 8% and 12.6% points lower for these vaccines.
Measles
Let’s take a closer look at measles. Nationally, almost 92 % of children received at least one dose of MMR. However, coverage varied by state – an observation unchanged from 2012. New Hampshire had the highest coverage at 96.3% and three states had coverage of only 86% (Colorado, Ohio, and West Virginia). Overall 17 states had immunization rates less than 90%. Additionally, 1 in 12 children did not receive their first dose of MMR on time. Why the concern? In 2013, there were 187 cases of measles including 11 outbreaks. A total of 82% occurred in unvaccinated individuals, and another 9% were unaware of their immunization status.
As of Aug. 25, 2014, there were 595 cases of measles in the United States in 21 states, according to the Centers for Disease Control and Prevention’s National Center for Immunization and Respiratory Diseases. This is the highest number of cases reported since endemic measles was eliminated in 2000. There were as a result of 18 outbreaks, representing 89% of the reported cases. Cases are occurring even in states where immunization rates are reported to be at least 90% – a reminder that there can be pockets of low or nonimmunizing communities that leave its citizens vulnerable to outbreaks when a highly contagious virus is introduced.
Since endemic measles was eliminated 14 years ago in the United States, many health care providers have never seen a case of measles or may not realize the impact it once had on our public health system. Prior to the initiation of the measles vaccination program in 1963, 3-4 million cases of measles occurred annually in the United States with 400-500 deaths and 48,000 hospitalizations. Approximately another 1,000 individuals were left disabled secondary to measles encephalitis. Once the vaccine was introduced, the incidence of measles declined 98%, according to "Epidemiology and Prevention of Vaccine-Preventable Diseases," 12th ed., second printing. (Washington, D.C: Public Health Foundation, 2012). Between 1989 and 1991, there was a resurgence of measles resulting in approximately 55,000 cases, 11,000 hospitalizations, and 123 deaths. The resurgence was caused primarily by the failure to vaccinate uninsured children at the recommended 12-15 months of age. Children younger than 5 years of age accounted for 45% of all cases. The Vaccines for Children Program was created in 1993 as a direct response to the resurgence of measles. It would ensure that no child would contract a vaccine preventable disease because of inability to pay.