California Home to 39 Percent of Nation’s Whooping Cough Cases
This guest post was written by Beth Jarosz, Research Associate, Population Reference Bureau.
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Pertussis, more commonly known as whooping cough, can cause serious and sometimes life-threatening complications. The risk is highest for infants and young children. Half of infants who get pertussis are hospitalized. For every 100 infants hospitalized for pertussis, one to two will die.
In June 2014, the California Department of Public Health announced that California was experiencing a pertussis epidemic. By the end of 2014, there were more than 11,000 reported cases of pertussis in the state.
For nearly fifty years, the number of pertussis cases in the United States remained steady: about 10,000 cases every year. During the last decade however, the number has steadily grown. In 2012, the outbreak peaked at 48,000 cases. Some say the rise can be attributed to improved diagnostic techniques, lower vaccination rates, or possibly, a less-effective vaccine that was introduced in 1991.
By 2014, the national number had dropped to 28,000 cases, though California, with 11,000 cases, was home to 39 percent of this figure—a vastly disproportionate share considering California’s population represents only 12 percent of the total U.S. population. Pertussis follows a predictable three-year cycle but the timing of those cycles doesn’t necessarily match up for California and the United States. Even accounting for this mismatch, California comprised a disproportionate share. Between 2006 and 2014, California accounted for about 12 percent of the U.S. population, but accounted for an average of 15 percent of pertussis cases.
On kidsdata.org, data on pertussis and other vaccine-preventable diseases can be found for each county in California, the state, and for the nation as a whole. The data are available through a partnership between the Population Reference Bureau (PRB) and kidsdata.org, a program of the Lucile Packard Foundation for Children’s Health.
Vaccines are one of the simplest, most cost-effective tools to improve public health. Vaccine-preventable diseases lead to illness, disfigurement, and disability. Globally, vaccine-preventable diseases remain a substantial cause of death, particularly for young children. Vaccines not only protect individuals, but with high rates of coverage, can also provide “herd” immunity: when many children within a community are immunized, infectious diseases are less likely to spread to those who cannot be immunized, for example, very young infants, or those for whom vaccines are not recommended due to certain illnesses, allergies, or immune problems.
Across counties and school districts in California vaccination coverage varies widely. For example, the proportion of kindergarten students in 2015 who received all state-required immunization ranges from 100 percent (Sierra County) to 72 percent (Nevada County). School district coverage rates vary even more. To put it into context, vaccination coverage across school districts in California varies as widely as it does between developed and developing regions around the world.
Low rates of vaccination and high rates of vaccination exemptions tend to be geographically clustered. As a result, vaccine-preventable disease outbreaks can, and do, occur where unvaccinated people cluster in schools and communities, even within countries with high overall vaccination coverage. And some diseases considered to be eliminated can reappear. In 2014, for example, the United States experienced a record 668 measles cases across 27 states, despite the fact that measles elimination was documented in the United States in 2000.
Researchers have identified the need for more effective vaccines to ward off future pertussis outbreaks. In the meantime, they stress that vaccination is essential for people of all ages.
For more information, see the two-part series from PRB: Progress Stalls On Vaccine-Preventable Diseases and Solutions to Reducing Vaccine-Preventable Childhood Diseases.
And join us for Vaccination and Vaccine-Preventable Childhood Diseases: Data and Trends, a webinar on July 8th that will explore global, national, and California trends in vaccination and vaccine-preventable childhood diseases.
Posted by kidsdata.org
This entry was posted on Thursday, June 25th, 2015 at 10:41 am. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.