Current Science and Vaccines: Pertussis

With SB 277 working its way (quite successfully) through the California legislature, I have spent a lot of time reviewing the available evidence around vaccinations. For those who are unaware, this bill would mandate that all children receive all doses of all vaccines mandated by the California Department of Public Health prior to entry into day care of school. Current law allows parents to delay or skip doses of vaccines or avoid them altogether by signing a personal beliefs exemption. This would take away that right. In effect, a child would be unable to attend public school or daycare if they were not fully vaccinated unless their doctor said that a vaccine or vaccines were medically contraindicated.

In the ACLU’s statement opposing this bill they note that public education is a fundamental right in California. They go on to say, “If there is, in fact, a compelling governmental interest in mandating that all students in every school be vaccinated against each of the enumerated diseases except for medical reasons, the bill should be amended to explain specifically what that interest is, where it exists, and under what conditions and circumstances it arises.” To simplify, the ACLU is saying, “If you are going to remove a child’s right to a public education, you better have a good reason to do this.” The good reason would be the scientific justification not just for all children to be fully vaccinated against the measles (the outbreak of which has caused so much concern), but to receive each dose of each vaccine on the schedule.

The oft repeated justification for SB 277 is that the unvaccinated are putting everyone at risk. This is a general statement. To support this statement with facts would require gathering evidence for each disease for which we have a mandated vaccination. The state Senator who authored SB 277 (a pediatrician named Richard Pan) has made some public statements with this in mind. Dr. Pan makes the case for pertussis (whooping cough). Here is the quote from his Op-ed dated April 14th in the Fresno Bee, “Unfortunately, as the number of unvaccinated people increases, diseases are returning.” This statement is followed up with an example: “in 2010, there were 9,120 cases of pertussis reported in California — more than any year since 1947. Ten babies died as a result of that outbreak.”

  • The assertion from Dr. Pan is that the over 9,000 cases of pertussis and ten babies who died were the result of increasing numbers of people who are not vaccinated for pertussis.

Is this assertion supported by any scientific studies? In a press release in 2013, the FDA states the following: “While the reasons for the increase in cases of whooping cough are not fully understood, multiple factors are likely involved, including diminished immunity from childhood pertussis vaccines, improved diagnostic testing, and increased reporting. With its own funds plus support from the National Institutes of Health (NIH), the FDA conducted the study to explore the possibility that acellular pertussis vaccines, while protecting against disease, might not prevent infection.”

Here is a description of that study: “The FDA conducted the study in baboons, an animal model that closely reproduces the way whooping cough affects people. The scientists vaccinated two groups of baboons – one group with a whole-cell pertussis vaccine and the other group with an acellular pertussis vaccine currently used in the U. S. The animals were vaccinated at ages two, four, and six months, simulating the infant immunization schedule. The results of the FDA study found that both types of vaccines generated robust antibody responses in the animals, and none of the vaccinated animals developed outward signs of pertussis disease after being exposed to B. pertussis. However, there were differences in other aspects of the immune response. Animals that received an acellular pertussis vaccine had the bacteria in their airways for up to six weeks and were able to spread the infection to unvaccinated animals. In contrast, animals that received whole-cell vaccine cleared the bacteria within three weeks.” (Please note that whole-cell vaccine still causes bacteria to be present and a risk of contagion for three weeks.)

They conclude with the following statement: “This research suggests that although individuals immunized with an acellular pertussis vaccine may be protected from disease, they may still become infected with the bacteria without always getting sick and are able to spread infection to others, including young infants who are susceptible to pertussis disease.” FDA and CDC scientists clearly believe that the current epidemic of pertussis has little (if anything) to do with the unvaccinated.

  • The FDA asserts that those recently vaccinated with the acellular pertussis vaccine are at risk of spreading the infection for up to 6 weeks. Those vaccinated with the whole cell vaccine (not available in the US) can spread the infection for up to 3 weeks.
  • The FDA blames the current pertussis epidemic on multiple factors, including diminished immunity from childhood pertussis vaccines, improved diagnostic testing, and increased reporting.

It is unclear why Dr. Pan and other supporters of vaccine legislation are out of step with current research on the pertussis vaccine. If they were up to date on this research, they would not include the pertussis vaccine in their legislation, and they certainly would not use it to justify their point of view that the unvaccinated and undervaccinated are putting the rest of the community at risk. That idea should be put to rest in regards to pertussis.




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