What is Herd Immunity?
“Herd immunity” occurs when enough members of a population are vaccinated against a disease to provide protection for those who have not developed immunity. A high percentage of herd immunity makes it difficult for disease to spread because there are so few people who are vulnerable to infection. This type of protection is particularly important for those who cannot receive immunizations due to age, a compromised immune system or other health problems.
How It Works
An individual can become immune to a disease by being vaccinated, or by becoming infected with the virus or bacteria that causes it. Because vaccines produce immunity without causing potentially life-threatening symptoms, they are an ideal way to create a community of disease-resistant people. Vaccinated people not only protect themselves from disease, they also stop the spread of disease to those who cannot or have not been vaccinated, limiting outbreaks. To achieve herd immunity, a certain percentage of people in a community must be vaccinated. The percentage varies for each disease.
What Happens When Herd Immunity Dips
For diseases such as measles, 92% of a population must be vaccinated to achieve herd immunity. For the 2014-15 school year, the Centers for Disease Control and Prevention reported that vaccination coverage among kindergarten children in 32 states and DC did not meet the Healthy People 2020 target of ≥95% coverage with two measles/mumps rubella (MMR) vaccine doses. Seven states had <90% two-dose MMR coverage. Across the United States, more people are being diagnosed with measles and other vaccine-preventable diseases due to fewer people being vaccinated and international travelers bringing diseases still rampant in other parts of the world to America.
Protect Your Family & Community at RediClinic
RediClinic offers all required vaccinations for school attendance for the 2016-17 school year, as well as a full range of vaccines for adults and children including chicken pox vaccine. If you need help determining which vaccines you need, our board-certified clinicians can help. We immunize patients age 18 months and older, seven days a week.