A regular Source column, Undercurrents explores issues, ideas and events developing beneath the surface in the Virgin Islands community.
Some Virgin Islands residents were surprised this fall when they answered calls to their unpublished cell phone numbers from persons who said they were conducting a survey on behalf of the national Centers for Disease Control and Prevention.
The survey is real. It’s an annual review of immunization rates across the U.S. And recent reports indicate that Virgin Islands households are somewhat behind much of the nation when it comes to vaccinating their children.
The CDC regularly sponsors surveys on a long list of health topics – so many that information officers were unable to respond to inquiries about the V.I. survey until it could be narrowed down by subject.
Then Ian Branam, press officer for the National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, confirmed that the CDC is wrapping up its 2016 National Immunization Survey. It’s actually the NIS Family of Surveys, since there is an overview survey plus separate surveys for families with teens and those with younger children. Results will be published in 2017.
The NIS survey is conducted in the 50 states, the District of Columbia, territories and selected local areas, Branam said. The data collection has been going on annually since 1994, although the territories were not included until 2009 and the Virgin Islands was left out of the 2014 survey, Branam said, because of funding shortages. Guam also was left out that year.
A look at the data published by the CDC for 2015 indicates the U.S. Virgin Islands immunization rates are either slightly or significantly below the national average for most categories.
For children ages 19 to 35 months, the national average for the MMR vaccine (against measles, mumps and rubella) is 91.9 percent. In the USVI it’s 77.2 percent.
The rate for the DTap vaccine, which is designed to protect against diphtheria and other diseases, is 84.6 percent nationally, but 65.8 percent for the Virgin Islands.
For rotavirus, the rates are 73.2 percent nationally, 43.3 percent in the V.I. For Hepatitis A, the rate is 59.6 percent nationally compared with 36.8 percent in the V.I.
The only category in which the Virgin Islands exceeded the national average for immunizations for young children was for Hepatitis B. The national average was 72.4 percent and the V.I. rate was 79.4 percent.
The picture was similar for teens, aged 13 to 17. The human papillomavirus vaccine is normally administered in three injections, over time. Rates for the vaccine were listed separately for males and females. For both genders, and for both the U.S. overall and the Virgin Islands, the rates dropped with each dose.
For girls in the U.S. the rates went from 62.8 percent after the first injection, to 52.2 percent, to 41.9 percent. In the Virgin Islands, the comparable rates were 40.4 percent, 25.8 percent and 16.4 percent.
For boys, the national averages were 49.8 percent, 39.0 percent and 28.1 percent, respectively. In the Virgin Islands they were 35.5 percent, 18.6 percent and 11.8 percent.
Tracking immunization rates helps establish the success of vaccines. For instance, diphtheria used to be a major killer. The CDC website estimates that before there was any known treatment, more than half the people who contracted it died from the disease. Even as late as 1921, the U.S. recorded 206,000 cases of diphtheria resulting in 15,520 mortalities.
Once a vaccine was introduced in the 1920s, the number of cases dropped quickly and it is generally not a threat today in the U.S.
The CDC has declared rubella virtually eliminated in the U.S. because of widespread use of vaccine. The number of mumps cases – which were counted at 186,000 before the vaccine was introduced in 1967, has declined by 99 percent, although there have been isolated outbreaks in 2006, 2009 and 2010.
Pneumococcal disease is a major cause of ear infections. Less commonly, it can cause lung and blood infections and infections of the brain and spinal cord, or meningitis. Before a vaccine was developed, the CDC recorded five million ear infections from it, 13,000 blood infections, 700 cases of meningitis and 200 deaths in children under age 5. Since the vaccine, disease rates have fallen 88 percent.
The CDC website says the data from NIS surveys is used to identify children at risk for vaccine-preventable diseases and to help determine how to increase immunization rates.
If you receive a call about the survey it may come from a Chicago area-code. The CDC contracted with an entity to actually do the research: the National Opinion Research Center at the University of Chicago.
As for how cell phone numbers were obtained, Branam said only that an “independent contractor” provides banks of numbers to NORC. Individual numbers are then selected at random from the banks.
He did not say how long the telephone survey takes, but according to its website, the CDC generally limits surveys to less than 20 minutes, and some are as short as 10 minutes.