Scientists have discovered new insights into how the lethal Ebola virus can persist in the body long after apparent recovery. In a recent study, researchers observed the virus remaining active and infectious in lab-created brain-like structures for extended periods, shedding light on why some Ebola survivors experience severe complications years later.
Ebola virus disease is a severe and often deadly infection characterized by symptoms such as fever, vomiting, bleeding, and organ failure. While some patients survive the acute phase, it has been known that the virus can evade detection within the body.
Evidence suggests that past Ebola outbreaks may have originated from individuals harboring the virus post-recovery. For instance, a 2021 outbreak in Guinea was linked to a survivor infected during the 2014-16 epidemic, indicating potential virus persistence for over five years before resurfacing.
The latest research, published in Nature Microbiology, indicates that the brain might offer a sanctuary for the virus to evade the immune system. Scientists from the Icahn School of Medicine at Mount Sinai and the Bernhard Nocht Institute for Tropical Medicine used miniature brain organoids to study the virus’s behavior in human brain tissue after infection. They observed Ebola and related viruses infecting the brain-like tissue, replicating for up to 120 days, and generating infectious viral particles by spreading between cells.
Furthermore, the study revealed that although the infected tissue triggered an immune response, it failed to completely eradicate the virus. This persistent infection could contribute to the development of inflammation affecting the eyes, meninges, or brain in some Ebola survivors, with rare cases of relapses occurring months or years post-recovery.
Researchers also identified genetic alterations in the virus as it persisted, potentially enhancing its survival within the body. Lead author Dr. Lina Widerspick highlighted how the organoids aid in understanding the mechanisms enabling Ebola virus persistence in the central nervous system and its long-term consequences.
Given the ongoing threat of Ebola in parts of Africa, the study findings may lead to improved treatments for survivors and a better grasp of how future outbreaks could stem from persistent infections. The researchers aim to expand their investigations to other viruses in the future.
