Warm-up: A Global Concern
Watch the short news report below about the recent increase in measles cases. Then, discuss the questions with a partner.
How measles outbreaks spread
An explanation of how measles spreads and the importance of herd immunity. Source: Reuters
Video Transcript
This person is infected with measles. In a population with no immunity, they can infect 12 to 18 others by coughing, sneezing, or talking. Those 12 to 18 people can then infect another 12 to 18 people each. [ 00:16 ]
Measles is one of the most contagious diseases in the world, much more so than chickenpox or COVID-19. And cases in the United States are on the rise, with researchers sounding the alarm that measles is approaching a return to endemic status. But it's also preventable. The measles-mumps-rubella or MMR vaccine is highly effective. People who get the two recommended doses are 97% less likely to catch the disease compared to unvaccinated people. [ 00:46 ]
This is a simulation of measles spreading through Leach, Texas, the county next to the current outbreak. It shows transmission with 95% of the population vaccinated or immune, with 85%, and with 75%. The simulation uses the FRED modeling system, which incorporates the size and locations of schools and businesses alongside census demographic data to simulate the spread of diseases. Each scenario was run 21 times, and the statistically median run was visualized. It's easy to see how even a small drop in the vaccination rate can break herd immunity and lead to outbreaks. [ 01:21 ]
"It's a leaky vaccine, and that problem is always going to be around." The increase in measles cases in the US is being fueled by a shifting political climate and unscientific claims that vaccines are unsafe, decades after the disease was declared eliminated. Vaccination rates among children there have been dropping for years, and researchers saw the outbreak coming. "It's scary. I mean, two children have died, you know, so I don't want that to be mine." [ 01:46 ]
In Texas, nearly half of the kindergartens that provide vaccination data had MMR vaccine rates lower than 95%, according to data from the Texas Department of State Health Services. Katherine Wells is the public health director of Lubbock. "And as we have more and more cases of measles, just statistically, we're going to see more individuals needing to be hospitalized. And unfortunately, you know, we are going to possibly see more deaths." [ 02:13 ]
Watch and Discuss
- According to the video, how contagious is measles compared to other diseases?
- The video uses a simulation to show how measles spreads. What happens when the vaccination rate drops from 95% to 85%?
- What is "herd immunity," and why is a 95% vaccination rate so important for it to work?
In recent years, a disease that was once nearly eliminated in many parts of the world has been making a surprising and dangerous comeback. That disease is measles. In this lesson, we'll look at the data behind the recent outbreaks, separate common myths from facts, and learn how to translate public health information into clear, actionable advice for our communities.
Data Walk: Understanding the Trend
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