Tick populations increase, new diagnostic tools and a new strain of Lyme
As someone who has dealt with Lyme disease, my eyes are always scanning the blogosphere for new information, studies and help for those who suffer; and the CDC believes this bacterial infection could be 10x more common than we know, even though 30,000 cases are reported each year.
Lyme disease is critical to detect at an early stage in order to prevent complications like, “arthritis, meningitis, facial palsy, and, in rare cases, myocarditis, or damage to heart muscle leading to sudden death”. However, researchers know that lyme can hide during the window period of infection before a detectable antibody response. So, scientists at the University of California, San Francisco, “decided to look for signs of Lyme disease not in the antibody response, but in the transcriptome, which amounts to the full range of messenger RNA molecules that is produced by a particular cell or tissue type”.
Let by Dr. Charles Chis, M.D., Ph.D., the group used RNA-seq to investigate the transcriptome (is the full range of messenger RNA, or mRNA, molecules expressed by an organism) in peripheral blood mononuclear cells. And what they found was that in the white blood cells of patients infected with tick-borne bacteria, there was a distinctive pattern in the transcriptome—a gene expression signature (a group of genes in a cell whose combined expression pattern is uniquely characteristic of a biological phenotype (the composite of an organism’s observable characteristics or traits) or medical condition). For the study, the researchers examined 29 patients before and after they had received a three week course of antibiotics and then six months later. When these patients were compared to others with bacterial or viral infections, the Lyme patients had distinctive gene signatures that persisted for at least three weeks, and some differences in the transcriptome lingered for six months.
From the article at GenEngNews:
“Early Lyme disease prior to antibiotic therapy was characterized by marked upregulation of Toll-like receptor signaling but lack of activation of the inflammatory T-cell apoptotic and B-cell developmental pathways seen in other acute infectious syndromes,” wrote the study’s authors. “Six months after completion of therapy, Lyme disease patients were found to have 31 to 60% of their pathways in common with three different immune-mediated chronic diseases. No differential gene expression signature was observed between Lyme disease patients with resolved illness to those with persistent symptoms at six months post-treatment.”
Which syndromes? That of systematic lupus erythematosus, rheumatoid arthritis, and chronic fatigue syndrome. It’s nice to finally see a report detailing what many have known for years; these symptoms are real, something is wrong. I feel like I’ve been saying that a lot lately as so many new studies have emerged.
This study, and what we assume (and hope) will come after, is welcome news as a new survey found the black legged tick reported in more than 45% of U.S. counties (it was 30% of counties in 1998)- this is twice the number of counties as in 1998.
UPDATE: Another reason to hope for further studies: researchers at the Mayo Clinic have discovered a new species of tick-borne bacteria. Named Borrelia mayonil (they named it after the Mayo Clinic) it too causes Lyme disease and has thus far, thankfully, only been found in the upper Midwest. There were 6 identified patients, although only one 1 had the tell tale bull’s-eye rash that is normally reported, and while they all had similar symptoms as those reported with Borrelia burgdorferi (until recently the only species known to cause Lyme in North America) they also had nausea and vomiting- as well as a “higher-than-expected concentration of bacteria in their blood”, reports the New York Times.
From the article:
“Fortunately, the antibiotic treatment normally used to treat Lyme disease appears to be effective against B. mayonii, Dr. Pritt said.
Dr. Bobbi Pritt, the medical director of the microbiology laboratory at the Mayo Clinic, where the new strain was first detected, recommended that patients with exposure to ticks in Minnesota and Wisconsin receive antibody and polymerase chain reaction testing to detect B. mayonii if they are concerned about Lyme infection but do not have the telltale bull’s-eye rash.
It is not yet clear where B. mayonii came from, Dr. Pritt said, though it does not seem to have recently diverged from B. burgdorferi. It may be that the species has always been present, but was picked up only with better detection tools, or that the new bacteria are increasing for some reason.”
Again, populations in the south don’t need to worry yet as the ticks seem to be spreading their territory up north only, and only 1-4 percent carry this new strain. But stay vigilant. Check yourself. Check your loved ones. Check your animals.
Source: Genetic Engineering and Biotechnology News and The New York Times
