Posted by: Chris Maloney | September 21, 2011

Vaccinations: Whooping Cough and MMR, Do We Need More?

Poster from before the 1979 eradication of sma...

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In a suprising study, researchers found a huge dropoff in the effect of vaccination for the whooping cough after only three years.  It was suprising because the researchers had thought the recent outbreaks of whooping cough were due to those darn unvaccinating parents, but it was the vaccinated children who were spreading the disease.

Right on time, we have a nasal spray for whooping cough.  Even though it’s been tested on animals alone, we can see at least a one year effect.  So let’s roll it out for global consumption.  Never mind that a nasal spray of a weakened disease can still cause a disease in others.

Which brings me to an ongoing concern I have about MMR.  When I was in college we had to revaccinated against MMR because it was found that the vaccine didn’t work well after eighteen years.  A recent outbreak of Mumps in Maine was among vaccinated college students.  So evidently they haven’t improved the vaccine and now I’m eighteen plus years out.  I don’t recall any recent “vaccinate the 36-year-olds” campaign.  So are we waiting for the adult outbreak of the disease before we revaccinate?

The point is that long-term vaccination policy is largely a matter of guessing because we don’t have the kind of long term data we need on the vaccines before they are rushed to market.  The longest study I could find covered children for six years after vaccination.  It is a very simple process to check for antibodies for decades after vaccination, but evidently no one is taking responsibility for  making sure our “vaccine defense shield” is up and running.  These are the same people who are in charge of cataloguing and reporting on vaccine side effects.  I’m not reassured.

So I have a request.  If we’re going to vaccinate everyone, could we at least do it in a scientific manner based on the available studies?  And maybe, just maybe, could we stop blaming the failure of vaccines to prevent all illness on the 2-3% of people who have a legitimate concern about vaccines and refuse to get them?  At 100% vaccination, we’d still only have 75-85% protection unless we start screening for antibodies because some children just don’t mount a long-term response.  Herd immunity has more to do with improving the delivery system than with “rounding up” the few outliers.

Vaccine. 2010 Oct 8;28(43):7047-53. Epub  2010 Aug 13.

Long-term immunity against pertussis induced by a single nasal administration of live attenuated B. pertussis BPZE1.

Abstract

Duration of vaccine-induced immunity plays a key role in the epidemiology and in the pattern of transmission of a vaccine-preventable disease. In the case of whooping cough, its re-emergence has been attributed, at least partly, to the waning of immunity conferred by current pertussis vaccines. We have recently developed a highly attenuated live vaccine, named BPZE1, which has been shown to be safe and to induce strong protective immunity against Bordetella pertussis infection in mice. In this study, we evaluated the long-term immunogenicity and protective efficacy induced by a single intranasal dose of BPZE1. Up to 1 year after immunization, BPZE1 showed significantly higher efficacy to protect adult and infant mice against B. pertussis infection than two administrations of an acellular pertussis vaccine (aPV). B. pertussis-specific antibodies were induced by live BPZE1 and by aPV, with increasing amounts during the first 6 months post-immunization before a progressive decline. Cell-mediated immunity was also measured 1 year after immunization and showed the presence of memory T cells in the spleen of BPZE1-immunized mice. Both cell-mediated and humoral immune responses were involved in the long-lasting protection induced by BPZE1, as demonstrated by adoptive transfer experiments to SCID mice. These data highlight the potential of the live attenuated BPZE1 candidate vaccine as part of a strategy to solve the problem of waning protective immunity against B. pertussis observed with the current aPV vaccines.

Copyright © 2010 Elsevier Ltd. All rights reserved.

PMID: 20708998
Pediatr Infect Dis J. 2002 Jun;21(6):555-61.

Vaccination with measles, mumps and rubella vaccine and varicella vaccine: safety, tolerability, immunogenicity, persistence of antibody and duration of protection against varicella in healthy children.

Source

Kaiser Permanente Vaccine Study Group, Oakland, CA 94612, USA. Henry.Shinefield@kp.org

Abstract

BACKGROUND:

Administration of M-M-R II (Measles, Mumps and Rubella Virus Vaccine, Live) and VARIVAX [Varicella Virus Vaccine Live (Oka/Merck)] given concomitantly at separate injection sites during the same office visit could increase vaccine compliance by reducing the number of health care visits for immunizations. We compared the safety and immunogenicity of M-M-R II and VARIVAX given concomitantly at separate sites (Group A) with administration of the two vaccines 6 weeks apart (Group B) as well as the persistence of varicella antibody and the duration of protection afforded by varicella vaccine.

METHODS:

A total of 603 healthy children, ages 12 months to 6 years, with no history of measles, mumps, rubella, varicella and zoster or vaccination against these diseases, were randomized to either Group A or B and were followed for clinical reactions and serologic responses to all four viral components. Children were enrolled from August through December, 1993. Subjects were followed for 5 years to evaluate persistence of varicella antibody and breakthrough varicella rates. We compared breakthrough rates to expected attack rates in unvaccinated children to produce estimates of vaccine efficacy.

RESULTS:

Both vaccine regimens were generally well-tolerated. There were no significant differences between the groups in the rates of fever, injection site reactions or rashes after vaccination. Seroconversion rates and geometric mean titers for measles, mumps and rubella were not significantly different between groups. The varicella seroconversion rate and percentage with glycoprotein-based ELISA titers > or = 5.0 units were similar between the two groups (99.5 and 92.5% vs. 100 and 94.8% for Groups A and B, respectively), but the geometric mean titers were statistically significantly different (13.2 for Group A and 17.9 for Group B). Varicella antibody persistence rates were >98 to 100% during 6 years of follow-up in both groups. Compared with historical rates, varicella vaccine efficacy during 5 years was estimated to be 90.5% (95% confidence interval, 86.2%, 95.0%) and 88.9% (95% confidence interval, 83.7%, 93.7%) in Groups A and B, respectively.

CONCLUSIONS:

Administration of M-M-R II and VARIVAX concomitantly at separate injection sites or 6 weeks apart was generally well-tolerated and immunogenic in healthy children 12 months to 6 years of age. VARIVAX administered with M-M-R II induced persistent immunity and long-term protection against breakthrough varicella infection.

PMID:
12182381

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