Author Interviews, Infections, JAMA, Pediatrics / 26.04.2019
How Long Does Protection from DTaP Vaccination Last?
MedicalResearch.com Interview with:
[caption id="attachment_48849" align="alignleft" width="200"]
Dr. Domenech de Cellès[/caption]
Dr. Matthieu Domenech de Cellès PhD
Biostatistics, Biomathematics, Pharmacoepidemiology, and
Infectious Diseases Unit, Institut Pasteur, Inserm U1181,
University of Versailles St-Quentin-en-Yvelines,
Versailles, France
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Most high-income countries now use acellular pertussis vaccines (called DTaP, which are sub-unit vaccines based on purified antigens of the bacterium Bordetella pertussis) to protect children against pertussis. Although clinical trials demonstrated the short-term effectiveness of DTaP vaccines, there was a growing concern that the duration of protection they conferred was not very long. Those concerns were mostly based on the results of a number of epidemiological studies, which showed that the relative risk of contracting pertussis increased substantially over time, typically by 20–40% every year since last vaccination.
Although such increases seem high, it was not immediately obvious how to interpret them—the more so because pertussis epidemiology is complex.
In our study, we developed mathematical models of pertussis epidemiology to try to understand what the results of recent epidemiological studies really meant about the effectiveness and the duration of protection of DTaP vaccines. The most interesting—and perhaps counterintuitive—finding of our study was that those results are fully consistent with highly effective DTaP vaccines, which confer long-term protection. This is a consequence of the fact that pertussis is highly contagious and that the immunity conferred by DTaP, though very high, is not perfect.
Dr. Domenech de Cellès[/caption]
Dr. Matthieu Domenech de Cellès PhD
Biostatistics, Biomathematics, Pharmacoepidemiology, and
Infectious Diseases Unit, Institut Pasteur, Inserm U1181,
University of Versailles St-Quentin-en-Yvelines,
Versailles, France
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Most high-income countries now use acellular pertussis vaccines (called DTaP, which are sub-unit vaccines based on purified antigens of the bacterium Bordetella pertussis) to protect children against pertussis. Although clinical trials demonstrated the short-term effectiveness of DTaP vaccines, there was a growing concern that the duration of protection they conferred was not very long. Those concerns were mostly based on the results of a number of epidemiological studies, which showed that the relative risk of contracting pertussis increased substantially over time, typically by 20–40% every year since last vaccination.
Although such increases seem high, it was not immediately obvious how to interpret them—the more so because pertussis epidemiology is complex.
In our study, we developed mathematical models of pertussis epidemiology to try to understand what the results of recent epidemiological studies really meant about the effectiveness and the duration of protection of DTaP vaccines. The most interesting—and perhaps counterintuitive—finding of our study was that those results are fully consistent with highly effective DTaP vaccines, which confer long-term protection. This is a consequence of the fact that pertussis is highly contagious and that the immunity conferred by DTaP, though very high, is not perfect.





Joanne B. Newbury, PhD
ESRC Postdoctoral Fellow
King’s College London
Social, Genetic & Developmental Psychiatry Centre
Institute of Psychiatry, Psychology & Neuroscience
London, United Kingdom
MedicalResearch.com: What is the background for this study?
Response: Urban living is one of the most well-established risk factors for adult psychotic disorders such as schizophrenia. However, less is known about the role of the urban environment in subclinical psychotic experiences in childhood and adolescence, such as hearing voices and extreme paranoia. These early psychotic experiences are a developmental risk factor for adult psychotic disorders and a range of other serious mental health problems such as depression and anxiety.
It is therefore important that we understand what factors might contribute to the development of early psychotic experiences so that we might be able to intervene and prevent their onset and progression.
In a cohort of over 2000 UK-born children (The Environmental Risk Longitudinal Twin Study), we have previously shown that subclinical psychotic experiences are also around twice as common among children and teenagers raised in urban versus rural settings. We have also shown that this appears to be partly explained by social features in urban neighbourhoods such as higher crime levels and lower levels of social cohesion.
However, no studies have examined the potential link between air pollution and psychotic experiences. This is despite air pollution being a major health problem worldwide (particularly in cities), and despite emerging evidence linking air pollution to the brain.