WASHINGTON, March 23 (Xinhua) -- The United States announced the elimination of measles in 2000, but in recent years measles has shown signs of a comeback. A new study recently published in the Journal of the American Medical Association shows that in measles cases in the United States, people deliberately do not receive the measles vaccine account for a considerable proportion.
The study, conducted by Professor Saad Omar of Emory University in the United States and colleagues, said that in recent years, there have been some vaccine-preventable outbreaks in the United States, which have aroused concern about "vaccine hesitation" and even refusal to vaccinate. To understand the correlation between refusal to vaccinate and the epidemic, they analyzed 18 published measles studies and found that 57 percent of the more than 1,400 measles cases in the United States since 2000 had no history of being vaccinated against measles.
In the United States, children receive two doses of the measles vaccine, the first at 12 to 15 months of age and the second at ages 4 to 6. But some U.S. states allow parents to not vaccinate their children for religious, philosophical, or medical reasons. The new study shows that of the 970 known measles cases recorded for vaccine exemptions, 574 had the conditions for vaccination but chose not to be vaccinated. Of these people, 71 percent (405) refused vaccinations because of religious beliefs and beliefs, not for medical reasons.
The study also analysed 32 reports of pertussis outbreaks, including more than 10,000 cases of pertussis in the United States since the 1970s. The results found that between 24% and 45% of patients in the five largest pertussis outbreaks were unvaccinated or under-vaccinated. Of the 8 known pertussis outbreaks in patient vaccine exemption records, 59% to 93% of patients deliberately did not vaccinate.
Saad Omar said the study has broad implications for vaccination practices and policies because it clearly shows that not vaccinating children carries considerable risks and harms, which is the fundamental reason for overturning parents' decision to refuse to vaccinate their children.
In comments in conjunction with the study, Professor Matthew Davis of the University of Michigan said that vaccination efforts in the United States had not been working best and that states with vaccine waiver laws should adopt stricter exemption management in terms of exemptions.
In recent years, the "anti-vaccine" movement has been on the rise from time to time. In addition to religious beliefs and personal beliefs, some American parents mistakenly believe that vaccination will cause autism, which has been repeatedly debunked by the US Centers for Disease Control and Prevention. In early 2015, when measles outbreaks occurred in 14 states, including California and New York, U.S. President Barack Obama called on parents to take their children to be vaccinated. (End)