At a recent hearing on SB277 State Senator Block asked if the CDC or AMA had data about the probability or likelihood of large or huge outbreaks occurring if a certain number of children remained unvaccinated. The answer, based on what history tells us, is that at current rates we are well protected: outbreaks are currently rare rare and huge ones are unheard of.
Measles was considered eradicated* nation-wide (eradicated meaning any small outbreaks that occurred over that time frame resulted from imported cases) with rates lower than or about equal to what we have in California today under current laws in place. 2015 MMR vaccination rate in California is 92.6%
2001-08 nation-wide vaccination rates for MMR from CDC Pink Book 12th edition
2001 - 91.4
2002 - 91.6
2003 - 93.0
2004 - 93.0
2005 - 91.5
2006 - 92.4
2007 - 92.3
2008 - 92.1
There were clusters of lower immunity throughout this period
just as there have always been and are today
As to what would happen if this bill passed, there is no metric
allowing us to foresee a future with a one or two percent increase in vaccination
rates. Historically a 1-3% fluctuation in national rates has occurred randomly from
year to year with no demonstrable effect on the number of cases.
One would need a well-funded, peer-reviewed study to even begin to try to measure the impact of a small increase in vaccination rates. Anything Senator Pan could produce in a matter of days would be nothing more than a guess. I don’t think we want to pass a bad bill on a guess.
One would need a well-funded, peer-reviewed study to even begin to try to measure the impact of a small increase in vaccination rates. Anything Senator Pan could produce in a matter of days would be nothing more than a guess. I don’t think we want to pass a bad bill on a guess.
*****
Senator Pan keeps talking about things getting worse because
we are not stopping the curve of increasing exemptions. But as he well knows, exemptions are no longer rising. Exemptions fell 20% last year and they fell even
more dramatically in the clusters of under-vaccination he so often refers to.
This is a result of his own bill - AB 2109 - which passed in 2012. The L.A
Times reports:
“Statewide, the rate of vaccine waivers for kindergartners
entering school in the fall declined to 2.5% in 2014 from 3.1% in 2013. Bigger
declines were seen in districts with some of the larger vaccine exemption
rates.
In the Santa Monica-Malibu Unified School District, the rate
fell from 14.8% to 11.5%; Capistrano Unified in south Orange County declined
from 9.5% to 8.6%; Beverly Hills Unified declined from 11.9% to 5%; and Laguna
Beach Unified declined from 15.1% to 2%, according to The Times' analysis.”
The last two areas mentioned achieved astonishingly large
drops in exemptions. With Beverly Hills exemptions falling 54% to and those in Laguna
Beach falling 86%
Overall MMR vaccination rates are stable and at or near
record highs
*****
Almost 7% of children are admitted to school without
vaccines on a conditional basis. These children are far more numerous than
those who have personal belief exemptions. This bill does not address those
conditional exemptions
According to press reports:
"These students may lawfully enter kindergarten on a
“conditional basis,” with some, but not all, of their required shots. The
condition is that they’ll get up to date soon."
This is another reason eliminating the personal exemption
will have almost no practical effect on measles risks
*****
Senators Marty Block and Loni Hancock asked:
Q: If my child is vaccinated and another is not, what are
the chances my child will get the measles
A: Since there is a 90% chance transmission would occur if
the child were not vaccinated, and the vaccine is 99% effective your vaccinated child's odds of getting the measles
would be less than 1%
Sources:
“Measles is so contagious that if one person has it, 90% of
the people close to that person who are not immune will also become infected.”
http://www.cdc.gov/vaccines/pubs/pinkbook/meas.html
“Studies indicate that, if the first dose is administered no earlier than the first birthday, greater than 99% of persons who receive two doses of measles vaccine develop serologic evidence of measles immunity”
“Studies indicate that, if the first dose is administered no earlier than the first birthday, greater than 99% of persons who receive two doses of measles vaccine develop serologic evidence of measles immunity”
