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Rare Disease Day is February 28. Rare diseases have specific legal definitions that are tied to support from various governmental programs around the world. Patient registries are a key part of the call for funding for rare disease research and are needed to advance the research on tick-borne diseases like Lyme borreliosis, bartonellosis, and babesiosis.
What is a rare disease?
There are an estimated 7000 rare diseases that affect approximately 300 million people worldwide. For comparison, the population of the United States is 336 million.
In the US, a rare disease is defined as a condition that affects fewer than 200,000 people. Because there are so many rare diseases, they affect about 1 in 10 people.
Rare Disease Day has been established on the last day of February to raise awareness about these numbers and what we can do to improve the lives of people with rare diseases. Although a large portion of rare disease advocacy is focused on genetic conditions, certain infectious diseases also fall into this category.
Rare infectious diseases include Borrelia, Bartonella, Babesia, Ehrichlia, etc. Although Borrelia is now estimated to infect more than 200,000 people in the US alone, it remains included in some government rare disease lists. We are still learning about these bacteria and their effects on humans, animals, and the environment.
Lyme disease and other flea- and tick-borne diseases are generally considered rare in the United States. While advocates have successfully overturned the belief that Lyme disease is a rare disease, it is still sometimes included on rare disease lists with a notation that underreporting has kept it on the list. The Centers for Disease Control (CDC) recently increased their estimated yearly prevalence of Lyme disease in the United States between 2010-2018 to 476,000 after accounting for additional commercial insurance claims data.
There are also sub-sets of Lyme borreliosis that meet the rare disease threshold through current reporting, such as those with chronic manifestations (Lyme carditis, Lyme arthritis) that may be caused by post-infection factors or by ongoing infection. The rare disease designation facilitates access to additional resources for researching these conditions and developing treatments.
Find out more about how patient registries help change the landscape for people with rare diseases.
Research and Development
Research and development of diagnostics is one of ways to improve the lives of people with rare diseases. A good example of this is the work Galaxy Diagnostics has done on vector-borne disease diagnostics. All of the bacteria we test for are elusive and hard to detect. This means we have to develop assays and technology that go beyond the limits of detection.
For the direct detection of Bartonella, Galaxy Diagnostics uses the Bartonella Digital ePCR test. This test uses sample enrichment and partitioning to detect Bartonella present in the sample at a genus level. The sample partitioning is done using droplet digital PCR, and we have already begun to explore its uses for other VBD testing.
A 2021 publication from researchers at North Carolina State University and Galaxy Diagnostics shows that ddPCR technology can confirm Borrelia, Babesia, and Bartonella infections all at once using multiplex testing. Rather than having to prepare multiple test samples for each target, the targets are simultaneously detected in a single reaction. This means less money and time, and a smaller sample is required to yield results.
Working together on a better count of people who have rare diseases and specific symptoms that go with those diseases and improving diagnostics leads to better treatments. Rare Disease Day is a day to reflect on the importance of all of these steps in improving the lives of people with rare diseases.