[UPDATE Feb 1:] The US measles outbreak continues to grow, with 107 cases now confirmed, the LA Times reports. The newspaper notes that cases in California, seven other states and Mexico are part of the outbreak linked to Disneyland.
Meanwhile, the US Centers for Disease Control and Prevention (CDC) has said that 84 confirmed cases of measles from 14 states were reported to them between Jan. 1 and Jan. 28, the majority of which are part of the outbreak linked to Disneyland. This information is preliminary and changing, noted Dr. Anne Schuchat, the assistant surgeon general of the United States Public Health Service and director of the CDC’s National Center for Immunization and Respiratory Diseases.
Schuchat said that the majority of those infected were not vaccinated or did not know if they had been vaccinated. “This is not a problem with the measles vaccine not working. This is a problem of the measles vaccine not being used,” she said.
“Measles is so contagious that if one person has it, 90 percent of the people close to the person who aren’t immune will also be infected,” explained Schuchat. “You can catch it just by being in the same room as a person with measles even if that person left the room because the virus can hang around for a couple of hours.”
The CDC continues to urge anyone not fully vaccinated to get their measles immunizations up to date to protect themselves as well as individuals who can’t be immunized (babies under six months, pregnant women and people with conditions that compromise their immune systems, such as leukaemia).
[UPDATE Jan 29:] The number of measles cases in the US continues to grow, with at least 95 confirmed cases in eight US states and Mexico, most of which have been linked to an outbreak that began spreading at Disneyland. The latest state to confirm a case linked to the theme park is Michigan, the LA Times reports.
In California, the state hardest hit by the outbreak, 66 students at Palm Desert High School who aren’t fully immunized for measles have been barred from school until Feb. 9 (or unless they can provide proof of vaccination or immunity) after a classmate may have been exposed to measles. The classmate, however, was cleared by the public health department.
In Alameda County, 30 babies were ordered to be isolated at home after they may have been exposed to the virus. Babies under six months cannot be immunized for measles.
There have also been measles scares at California State University, Long Branch, where a student who had measles may have exposed as many as 20 others, and at Santa Monica High School, where a baseball coach tested positive for measles. The risk at the high school was considered low because all students on the team had been fully immunized.
In Arizona, 195 children may have been exposed to measles after a woman with measles visited Phoenix Children’s Hospital’s East Valley Center on Jan. 20 and 21, USA Today has reported. Health officials recommended all exposed children be kept home from daycare and school for the 21-day incubation period if they have not had at least one dose of the measles vaccine.
Public health officials in California say it is safe for those who have been immunized to go to Disneyland and other places where there are large crowds. However, they continue to caution those not immunized and parents of newborns too young to be immunized to stay away from the theme park and places where they may come in contact with international travellers, such as airports.
[UPDATE Jan. 23:] In response to this outbreak, the American Academy of Pediatrics has released a statement urging parents to get their kids vaccinated. “A family vacation to an amusement park—or a trip to the grocery store, a football game or school—should not result in children becoming sickened by an almost 100 percent preventable disease,” says Errol R. Alden, the executive director and CEO of the AAP. “The measles vaccine is safe and effective. The AAP urges parents to have their children immunized against measles, as well as other infectious diseases, and to talk with their child’s pediatrician if they have questions about any of their child’s recommended vaccines.”
Yvonne Maldonado, vice-chair of the AAP Committee on Infectious Diseases, adds: “Delaying vaccination leaves children vulnerable to measles when it is most dangerous to their development, and it also affects the entire community. We see measles spreading most rapidly in communities with higher rates of delayed or missed vaccinations. Declining vaccination for your child puts other children at risk, including infants who are too young to be vaccinated, and children who are especially vulnerable due to certain medications they’re taking.”
[Original post Jan. 22:] The measles outbreak linked to Disneyland has now hit 70 cases, and public health officials are cautioning those not immunized to avoid Disneyland and advising parents of newborns too young to be immunized to stay away from places where there are large numbers of people. And in Orange County, officials have barred two dozen students who can’t show proof of immunization from one high school after a student with measles attended classes.
Orange County’s public health officer says the same policy, intended to prevent the spread of the highly infectious disease, will be instituted at any other schools if necessary: “If there is a case in the school and their child is not immunized, they will be removed from the school for 21 days,” Dr. Eric Handler told the LA Times. “From an epidemiological standpoint, in order to prevent the spread of the disease, this is a necessary measure.” According to the LA Times, Orange County has lower than average vaccination rates.
The outbreak of this highly infectious disease has been described as the worst California has seen in 15 years. San Diego County has instituted a mandatory 21-day quarantine for anyone without proof of vaccination who came in contact with five patients suspected to have measles. A handful of related cases have also cropped up in five other states and Mexico—not surprising given people travel from all over to visit the amusement park.
Five Disneyland employees have tested positive for measles, two of whom are among the handful of cases involving a person who had been vaccinated for it. All Disneyland employees who have been in contact with the five ill employees have been asked to show proof of vaccination or take a blood test to prove immunity, and those who could not show proof have been put on paid leave until their status can be determined. Vaccinations have been offered to all employees.
Why do some people who have been vaccinated end up getting measles? No vaccination offers absolute protection, but two doses of the measles vaccine offers better protection than a single dose, and prior to 1989, only one dose was standard in the US. In Canada, a second dose was added to provincial vaccination schedules in 1996–97, and catch-up programs were instituted in most areas for school-aged kids. However, if you were born in or after 1970 and you’re not sure if you got that second dose, you may want to talk to your doctor about a booster.
Even if you have no plans to travel to Disneyland or California, there are many other places in the world where measles is endemic. The Public Health Agency of Canada recommends all travellers make sure their measles vaccination is up to date before a trip. Even travel through an international airport can increase your risk of exposure.