Seven years ago, Minnesota Public Health Laboratory scientists could sequence maybe a thousand DNA bases in a gene from a virulent, disease-causing microorganism. And it took a day to do it. Sara Vetter, PhD, who manages the laboratory’s infectious disease program, said “Now we can sequence five million bases in about two days. Instead of looking at one gene, we can look at all the genes in a microbe like Salmonella.”
What difference does this make?
In 2018, Minnesota confirmed 152 cases of Legionnaires’ disease. Thanks to genetic testing—and access to a public health database of Legionella strains—health authorities determined that only a small number of cases could be traced to a definite source: Five cases involving genetically identical microbes were associated with an outbreak at a senior living community, one case was linked to a hospital outbreak detected in early 2019, and six cases were associated with outbreaks in other states. The remaining 140 cases were genetically unique—that is, not closely related to each other or to any known outbreak strain—and thus deemed random or “sporadic.”
This information was crucial to determine where health authorities should concentrate their resources for maximal public health impact. Such is the power of genetic, or molecular, data.
But, as powerful as molecular data can be, it cannot be taken for granted. Genetic testing programs require sophisticated instrumentation, complex analytical protocols and expertise in areas like next generation sequencing and bioinformatics.
Since 2013, APHL has worked to assure public health laboratories have both the technology and workforce expertise to generate and interpret molecular data.
The cumulative impact of years of APHL support for genetic testing is evident in Minnesota. In 2016, the Minnesota Public Health Laboratory was the first state public health laboratory to host a bioinformatics fellow. In 2019, the laboratory supplied two instructors for the APHL/CDC bioinformatics academies.
In 2013, the Minnesota Public Health Laboratory sequenced 58 samples of just one pathogen type—Salmonella. In 2019, the laboratory sequenced 5,000 samples spanning more than 34 different pathogens.
“Without all the support APHL has provided to our laboratory, directly and indirectly, we wouldn’t be where we are today,” said Vetter. “And that would be a great loss for public health.”