Lately the news has contained many stories of illness or death that could have been prevented by vaccination. Although in 2019 the stories have mostly been about measles, in 2016 it was pertussis, or whooping cough, as it was in 2012, and 2004-2005.
The Centers for Disease Control estimates 24.1 million cases of whooping cough occur each year worldwide, resulting in 160,700 deaths. As with measles, the most effective way to prevent whooping cough is through vaccination.
Recently Young Juhn, M.D., a clinical informatistician, pediatrician and population health researcher at Mayo Clinic, led a study using spatio-temporal, or hot-spot, analysis to better understand the pertussis outbreaks. His team analyzed the onset and spread of pertussis during two time periods, in Olmsted County, Minnesota, using a microbiology database and the Rochester Epidemiology Project. This unique medical records linkage system and longtime regional research collaborative originated in Olmsted County, Minnesota, and now includes 27 counties across Minnesota and Wisconsin.
Dr. Juhn and his team found that during 2004-2005 and 2012, whooping cough was diagnosed in Olmsted County at rates 5-10 times higher than average, as well as significantly higher than across the rest of Minnesota. Only whooping cough cases with diagnosis as confirmed by laboratory testing conducted by Mayo Clinic Laboratories were included. No individuals were counted who did not have confirmed laboratory results.
They found that adolescents (age 11-13) had the highest incidence rate during both outbreaks. Furthermore, the researchers observed that early in both outbreaks, a specific geographic area/neighborhood had the highest incidence levels.
"Geographic locations have not been typically taken into account as a risk factor for infectious diseases," says Dr. Juhn. "However, our study results indicate that we need to change that."
Dr. Juhn can't say yet why that neighborhood was disproportionately affected, but he has some theories he is pursuing with his research team.
"Our next steps are to further characterize children living in this area compared to other areas," he says. "We want to examine school attendance, school bus route, after school activities, and so forth."
In addition, Dr. Juhn and his fellow researchers see an opportunity to use the rich data of electronic health records, including the resources of the Rochester Epidemiology Project, to examine how well the pertussis vaccine helps provide herd immunity, and also whether its protective effect lessens over time since vaccination.
While the team has several questions they still want to answer, Dr. Juhn says, "Vaccination is still the best strategy to prevent whooping cough and reduce its spread."
Dr. Juhn also encourages parents and teachers to encourage hand washing and other precautions to prevent spread of infectious diseases. He also says that as public health organizations become aware of whooping cough diagnoses, coordination with the school district for early recognition and timely isolation of cases could help prevent spread.
In their continuing investigation around whooping cough, Dr. Juhn and his team are planning to test and implement an innovative approach at a population level called precision population medicine.
He says that the geographic hotspots identified now and in the future could help them to identify "first, which children and adolescents reside in such geographic areas; second, which are susceptible to whooping cough due to not up-to-date vaccinations; and finally, which schools they attend."
"We need to educate parents and teachers about whooping cough and other common infectious diseases – both about symptoms and prevention," Dr. Juhn says. "In Olmsted and Dodge counties in particular, we have partnerships with the schools and public health department already, through which we may be able to offer this and other vaccinations at school settings such as the School Flu Vaccine Program, making it easier and more timely for parents to protect their children."
Dr. Juhn reiterates that public health issues such as this are best addressed through interagency coordination – wherever the outbreak may occur. He believes that understanding historical trends in the spread of disease is "an important aspect of improving a community’s preparedness for future outbreaks of emerging and re-remerging infectious diseases."
"It also could provide an opportunity to assess and address unmet health needs of geographically under-served populations leading to health disparities," he says.
In addition to Dr. Juhn, the research team included:
About the Rochester Epidemiology Project
The Rochester Epidemiology Project (REP) is a collaboration of clinics, hospitals, and other medical facilities in Minnesota and Wisconsin and involves community members who have agreed to share their medical records for research. Using medical record information, medical scientists can discover what causes the diseases, how patients respond to medical and surgical therapies, and what will happen to patients in the future. Research studies conducted in the local community may improve the health of people both locally and globally. https://rochesterproject.org
The REP receives administrative support from the Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery. Improving public health is in alignment with the center's overall goal to transform the experience of health and health care.
Tags: Center for the Science of Health Care Delivery, Chung-Il Wi, epidemiology, Euijung Ryu, Findings, immunization, News, personalized medicine, pertussis, Progress Updates, Rochester Epidemiology Project, vaccines, whooping cough, Young Juhn