The following post first appeared on FactCheck.org.
Rep. Mo Brooks and potential presidential hopeful Ben Carson both suggested a connection between illegal immigration and the spread of diseases such as measles in the United States. Though it is often difficult to pinpoint precise origins of disease outbreaks, there is no evidence supporting a link between the recent outbreaks and illegal immigration.
Brooks, a Republican from Alabama, was asked about the current measles outbreak in an interview with radio host Matt Murphy (at the 14:24 mark). The congressman said the immunization practices in the home countries of immigrants who are living in the U.S. illegally could be responsible for outbreaks.
Brooks, Feb. 3: I don’t think there is any health care professional who has examined the facts who could honestly say that Americans have not died because the diseases brought into America by illegal aliens who are not properly health care screened, as lawful immigrants are. It might be the enterovirus that has a heavy presence in Central and South America that has caused deaths of American children over the past six to nine months, it might be this measles outbreak — there are any number of things. … [U]nfortunately our kids just aren’t prepared for a lot of the diseases that come in and are borne by illegal aliens. You have to have sympathy for the plight of the illegal aliens, I think we all understand that. But they have not been blessed with — in their home countries — with the kind of health care, the kind of immunizations that we demand of our children in the United States.
The first example Brooks mentioned refers to an outbreak of enterovirus D68 in 2014, which sickened many thousands and did kill at least two children. During that outbreak, some implied that it was connected to illegal immigration, in particular because of a surge of children crossing the U.S.-Mexico border from Honduras, Guatemala and El Salvador. The Centers for Disease Control and Prevention, however, has specifically noted that children entering the country illegally from Central America present little risk of spreading diseases among the public.
Furthermore, the CDC found that the strain of enterovirus was genetically similar to strains found in the U.S., Europe and Asia in previous years, suggesting the outbreak did not start via immigration from Central and South America. A 2013 study published in the journal Virology found that only 3 percent of 3,375 patients with flu-like symptoms across a variety of Latin American countries actually had any type of enterovirus, and an even smaller proportion had the relevant strain to the U.S. outbreak.
The measles outbreak in the U.S., which includes most of the 102 cases in 14 states between Jan. 1 and Jan. 30 this year, likely did originate from outside this country. Whether it came from an immigrant living in the U.S. illegally, however, is unknown. According to Anne Schuchat, an assistant surgeon general and director of the CDC’s National Center for Immunization and Respiratory Diseases, illegal immigration is not the likely culprit.
“Although we aren’t sure exactly how this year’s outbreak began, we assume that someone got infected overseas, visited the Disneyland parks and spread the disease to others,” she said in a press briefing on Jan. 29. For example, travelers to the Philippines could have been exposed to the disease, as that country suffered an outbreak possibly involving more than 50,000 cases last year. Schuchat did say that there have been no confirmed cases of transmission from the Philippines yet this year; Indonesia, India and the United Arab Emirates are among the countries currently under investigation as a source for the outbreak.
Between January and May 2014, the CDC reported 288 cases of measles and was able to pinpoint the origin for all but eight of them. The CDC counted 45 “direct importations” of the disease, which included 40 U.S. residents returning home from abroad and five foreign visitors; 22 of those were transfers from the Philippines. Only three came from the Americas, and the rest came from Southeast Asia and Europe.
Measles cases in the U.S. have spiked in recent years, with 644 reported cases in 2014. One large outbreak, with 383 cases, occurred last year among Amish communities in Ohio, where vaccination rates are very low. The 102 cases so far in 2015 puts the country on pace to reach an even higher number this year. Since 2000, the fewest cases of measles in the U.S. occurred in 2004, when there were only 37 confirmed cases.
Notably, the recent cases of measles that do occur in the U.S. are concentrated among unvaccinated individuals. On Jan. 21, the California Department of Public Health said that 28 of 34 of the confirmed cases of measles involved people who were not vaccinated. Schuchat, in her Jan. 29 briefing, noted that the majority of cases are in people who “did not get vaccinated or don’t know whether they have been vaccinated.”
Brooks also contended that “illegal aliens” come from countries that don’t have “the kind of immunizations that we demand of our children in the United States.” Brooks would have been correct if he were talking about the 1980s, when Central American countries showed low rates of vaccination. But since 2000, the vaccination rates of Central American countries have been largely on par with or have exceeded that of the United States.
According to the World Health Organization, the United States in 2013 had a measles vaccination rate for 1-year-olds of 91 percent. Though Mexico’s rate dropped to 89 percent in 2013, it had been at 95 percent or higher for every other year since 2000. Guatemala’s 2013 rate was 85 percent, down from 93 percent the previous year. Honduras also had a coverage rate of 89 percent, down from above 90 percent in previous years. El Salvador’s rate was 94 percent in 2013.
Brooks was not alone in suggesting illegal immigration could be connected to the spread of disease. Speaking with CNN’s Jake Tapper, Ben Carson — a retired neurosurgeon who is considering running for the Republican presidential nomination — echoed that sentiment.
Carson, Feb. 3: These are things that we had under control. We have to account for the fact that we now have people coming into the country, sometimes undocumented people, who perhaps have diseases that we had under control. So now we need to be doubly vigilant about making sure that we immunize our people to keep them from getting diseases that once were under control.
Though the U.S. did declare measles “eliminated” in 2000, the declining vaccination rate in California and elsewhere in the U.S. has led to the increase in cases and outbreaks. The CDC’s reporting on measles outbreaks over the last 15 years has concerned only U.S. travelers returning from abroad and spreading the disease, or refugees from countries such as Burma. In earlier reports on outbreaks that occurred in 2001 and again in 2013, the CDC noted that children adopted from China brought measles into the country. China’s measles immunization rate has held steady at 99 percent over the last five years.
Another report from the CDC on measles outbreaks between 2001 and 2004 cited U.S. residents returning from travel abroad as a major source of the disease, along with foreigners visiting this country. “Importation of measles from foreign visitors is unavoidable because no regulations are in effect requiring vaccination of visitors,” the report noted.
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