Importance of vaccinations

Diseases that used to be common in this country and around the world, including polio, measles, diphtheria, pertussis (whooping cough), rubella (German measles), mumps, tetanus, rotavirus, and influenza can now be prevented by vaccination.

Thanks to a vaccine, one of the most terrible diseases in history – smallpox – no longer exists outside the laboratory. Over the years, vaccines have prevented countless cases of disease and saved millions of lives.

Immunity protects from disease

Immunity is the body’s way of preventing disease. The immune system recognizes germs that enter the body as “foreign invaders” (called antigens) and produces proteins called antibodies to fight them. The first time a child is infected with a specific antigen (say measles virus), the immune system produces antibodies designed to fight it. This takes time, and usually the immune system can’t work fast enough to prevent the antigen from causing disease, so the child still gets sick. However, the immune system “remembers” that antigen. If it ever enters the body again, even after many years, the immune system can produce antibodies fast enough to keep it from causing disease a second time. This protection is called immunity.

Vaccines contain the same antigens (or parts of antigens) that cause diseases. For example, measles vaccine contains measles virus. But the antigens in vaccines are either killed, or weakened to the point that they don’t cause disease. However, they are strong enough to make the immune system produce antibodies that lead to immunity. In other words, a vaccine is a safer substitute for a child’s first exposure to a disease. The child gets protection without having to get sick. Through vaccination, children can develop immunity without suffering from the actual diseases that vaccines prevent.

Research has shown that vaccines are safe, effective, and have had a positive impact on population health.

The Centers for Disease Control and Prevention (CDC) recommends receiving vaccinations for certain diseases. Parents should consult a physician about which vaccinations their children should receive and when they should receive them.

Vaccination policies in California

Although the overall vaccination rate among kindergarteners in California is about 90 percent, there are areas within the state that have considerably lower rates.[1] This is largely due to the increased use of personal belief exemptions, which until the passage of SB 277, described below, allowed parents to send unvaccinated children to school for non-medical reasons.  A recent study found that the use of personal belief exemptions increased by 360 percent from 1996 to 2010.

Personal belief exemption rates vary by region, as seen in the image below:

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Herd immunity occurs when a community is protected against an outbreak because a significant portion of individuals in the community are immunized

Therefore, while herd immunity may be adequate in some regions of California, there are other areas for which low vaccination rates pose a threat to children’s health.

Senate Bill 277

Senate Bill 277 was signed into law in 2015 and took effect July 1, 2016, and prohibits public or private schools, child care centers, and similar institutions from accepting incoming students who have not received recommended vaccinations.

Prior to enactment of SB 277, the law allowed an exemption to this mandate for individuals (1) for whom vaccines would not be safe due to a medical condition, such as a child who is undergoing chemotherapy, and (2) who have personal beliefs against immunization.

Senate Bill 277 eliminated the personal beliefs exemption, with the goal of promoting health and safety in schools by increasing herd immunity throughout the state.