5 Clinical Updates in Tick-borne Disease Research
Summer is in full swing and Americans are enjoying the outdoors before the cold weather comes back. With warm weather, however, come ticks and tick-borne diseases. What is new in this area of research? In the slides below, find details on 5 key pieces of research in tick-borne diseases, including an investigational Lyme disease vaccine and insight into the spread of Rocky Mountain spotted fever.
1. Most widely reported pathogen in US is Lyme disease-causing Borrelia burgdorferi. A team of US Centers for Disease Control and Prevention (CDC) researchers combined nationwide tick surveillance records from 2004 through 2021 with additional data on pathogen testing in blacklegged ticks from published research studies and from archives on public health department websites. Published in the Entomological Society of America's Journal of Medical Entomology, the results offer the most current snapshot of the geographic range of 7 significant human disease-causing pathogens known to be transmitted by blacklegged ticks (Ixodes scapularis) and western blacklegged ticks (Ixodes pacificus). Most widely reported was the bacteria Borrelia burgdorferi, which causes Lyme disease, found in 476 counties across 29 states and the District of Columbia.
2. Phase 3 trial underway of Lyme disease vaccine candidate, VLA15. Pfizer and Valneva announced on August 8, 2022, the initiation of a phase 3 clinical trial, Vaccine Against Lyme for Outdoor Recreationists (VALOR), to evaluate the efficacy, safety and immunogenicity of their investigational Lyme disease vaccine candidate, VLA15.
3. US Lyme disease diagnosis rose 357% in rural areas over past 15 years. Lyme disease has experienced notable growth in the US over the past 15 years and, as a result, has become an illness of increasing national concern. From 2007 to 2021, private insurance claim lines with Lyme disease diagnoses rose 357% in rural areas and 65% in urban areas. These and other findings on this tick-borne, bacterial illness were just released by FAIR Health, an independent nonprofit organization that maintains a database of national private health insurance claims.
4. Over 14% of global population has likely had Lyme disease. More than 14% of the world’s population probably has, or has had, tick-borne Lyme disease, as indicated by the presence of antibodies in the blood, reveals a pooled data analysis of the available evidence, published in the open access journal BMJ Global Health. The reported estimated global Borrelia burgdorferi sensu lato (Bb) seroprevalence was 14.5% (95% CI, 12.8%-16.3%), and the top 3 regions of Bb seroprevalence were Central Europe (20.7%; 95% CI, 13.8%-28.6%), Eastern Asia (15.9%; 95% CI, 6.6%-28.3%), and Western Europe (13.5%; 95% CI, 9.5%-18.0%).
5. Recent study shows how deadly Rocky Mountain spotted fever spreads. Findings from a new study are providing important insights into the spread of Rocky Mountain spotted fever (RMSF), which is transmitted from dogs to people through ticks. The new data are being used to create models that could help predict, and possibly prevent, future outbreaks. To better understand why RMSF emerged as a new vector, researchers from Midwestern University in Glendale, Arizona, performed a detailed analysis of brown dog ticks, canine and human infections, and climatic data in Arizona, New Mexico, California, and Mexico. Investigators found that the spread of RMSF is due to a combination of 4 factors: (1) the presence of a distinct population of brown dog ticks, (2) variation in the genetic strain of the causative agent Rickettsia rickettsii, (3) distribution of canine seroprevalence across the region, and (4) geographic and climatic factors.
