Sen. Rand Paul gave false and misleading statements about vaccine safety in two separate interviews, including a claim that "many" children have developed "profound mental disorders" after vaccinations.

There is no evidence that any currently recommended vaccine causes brain damage or other mental disorders in otherwise healthy children. Severe reactions do occur but are extremely rare.

Vaccine safety has become a central topic in recent weeks as a measles outbreak that began at Disneyland in California has spread. Between Jan. 1 and Jan. 30, the Centers for Disease Control and Prevention reported that 102 people had confirmed cases of measles, a disease that the CDC declared "eliminated" from the United States in 2000 because of the highly effective vaccine. In recent years, a small but growing number of parents has avoided the measles, mumps and rubella vaccine because of fears related to debunked and fraudulent science.

"The comments made by Rand Paul are worrisome, as they don't seem to be based on scientific data," said Marietta Vazquez, an associate professor of pediatrics at Yale University School of Medicine and a member of the U.S. Advisory Committee on Immunization Practices, "Indeed, there are no reported cases of profound mental disorders that I know of."

There have been some reports of "lowered consciousness" or permanent brain damage after a vaccine is given for diphtheria, tetanus and pertussis (whooping cough) or measles, mumps, and rubella (MMR), but the CDC says that these are so rare that a cause-and-effect relationship cannot be determined. The diseases these common vaccines prevent, on the other hand, can cause serious problems: One in 1,000 children with measles will develop a swelling of the brain "that can lead to convulsions and can leave the child deaf or mentally retarded," and between 1 and 2 in 1,000 will die, according to the CDC. Pertussis is even more dangerous: One in 300 children with whooping cough will develop brain complications, and 1.6 percent will die. Vazquez said in an email that serious adverse events can indeed occur with common vaccines, but they are exceptionally rare. Serious allergic reactions to the MMR vaccine, for example, occur at a rate of less than 1 in every 1 million doses, according to the CDC.

Immigration and disease

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. 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. 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. 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.

Chip Tuthill lives in Mancos. Website used: www.factcheck.org.