Mayo Clinic scientists tracked how measles virus mutated in a fatal brain disease. The study warns of potential new cases as measles resurges among the unvaccinated. Using advanced genetic sequencing, researchers reconstructed the viral spread in the brain, discovering mutations driving the virus from the frontal cortex.
Roberto Cattaneo, Ph.D., a Mayo Clinic virologist who is a co-lead author on a new PLOS Pathogens study said, “Our study provides compelling data that shows how viral RNA mutated and spread throughout a human organ — the brain, in this case. Our discoveries will help studying and understanding how other viruses persist and adapt to the human brain, causing disease. This knowledge may facilitate the generation of effective antiviral drugs.”
Measles is highly contagious, spreading through coughs or sneezes. Dr. Cattaneo pioneered research on how the virus causes a rare, lethal brain disease, SSPE, in 1 in 10,000 cases. It takes 5-10 years post-measles for the virus to mutate and spread in the brain, leading to symptoms like memory loss and seizures. Dr. Cattaneo’s work helped as vaccinations reduced SSPE cases.
Measles is returning due to vaccine hesitancy and missed shots, worsened by the pandemic. A CDC report shows an 18% rise in measles cases and a 43% increase in deaths in 2021 compared to 2020. With the resurgence, there’s concern about the rise in SSPE cases. Iris Yousaf, co-author of the study, emphasizes the importance of vaccination in preventing this severe disease. Using modern genetic sequencing, the study aims to understand more about SSPE.
Drs. Cattaneo and Yousaf collaborated with the CDC, studying a person who had measles as a child and later developed SSPE as an adult. They examined 15 brain specimens, conducting genetic sequencing. The research unveiled that once the measles virus entered the brain, its genetic material changed in harmful ways. The virus replicated its genome, creating slightly different versions. This process repeated, forming a diverse population of genomes.
Dr. Cattaneo said, “In this population, two specific genomes had a combination of characteristics that worked together to promote virus spread from the initial location of the infection — the frontal cortex of the brain — out to colonize the entire organ.”
The following research focuses on how specific mutations help the virus spread in the brain. Experiments are planned in cultivated brain cells and brain-like cell clusters (organoids). Understanding this may aid in developing antiviral drugs. Yet, intervening in advanced stages is tough. The best way to prevent SSPE is through measles vaccination.
In conclusion, this Mayo Clinic study marks a significant step in understanding the intricate details of how the measles virus spreads in the human brain. The findings open avenues for future research and potential applications in antiviral drug development while underscoring the crucial role of measles vaccination in preventing severe complications.
Journal reference:
- Iris Yousaf, William W. Hannon et al., Brain tropism acquisition: The spatial dynamics and evolution of a measles virus collective infectious unit that drove lethal subacute sclerosing panencephalitis. PLOS Pathogens. DOI: 10.1371/journal.ppat.1011817.