Ebola May Have Found Another Place to Hide Out: The Lungs

Previously, the Ebola virus has been found to remain in patients’ semen a number of days after it can be detected in the blood. Now, it appears that the virus may have found another place to escape detection: the lungs.

Researchers from the National Institute for Infectious Diseases “Lazzaro Spallanzani,” (INMI) in Rome, Italy, have found evidence that suggests Ebola can actually replicate in the lungs of an individual recovering from the infection. Their findings, which can be found in PLOS Pathogens, may offer a better understanding of how Ebola is transmitted as well as provide insight into new approaches to treating the virus, which has claimed over 11,000 lives in West Africa.

The largest unprecedented outbreak of Ebola that the world has seen thus far occurred in West Africa between 2013 and 2016. Since then, researchers from around the world have been putting their efforts into controlling the virus by learning more about it. According to a recent press release, “Lab studies, animal studies, and observations of evacuated patients treated in Europe and the United States have suggested that Ebola might cause lung damage by replicating itself in lung tissue.” Despite these suggestions, there has not yet been concrete evidence to validate lung infections caused by Ebola.

In order to examine this potential link further, researchers from INMI took a closer look at one patient during treatment for and recovery from the virus; the patient was a healthcare worker who had been evacuated from West Africa to receive treatment in Rome.

In their study, the researchers compared the levels of viral RNA fragments—known to be linked to Ebola replication—in both the patient’s lungs and blood. They found that, “viral RNA and viral replication markers remained in the lungs for about five days after it was no longer detectable in the blood.”

This means that it’s possible that the virus was replicating within the lungs, a place where the RNA could remain longer than it could in the blood. The authors noted, however, that active replication was also possible due to the fact that “the presence of RNA for both total and replication markers” were found in the patient’s lungs.

The authors concluded, “We demonstrated a long persistence of EBOV replication markers within the respiratory tract, compared to plasma. This suggests a major role of the respiratory tissues in the pathogenesis of Ebola virus disease.”

Future studies will be needed in order to gain a stronger understanding of the potential link between lung infection and Ebola and whether this may actually be a factor when it comes to transmission among humans, according to the authors.

These findings come on the heels of Merck, Sharpe, and Dohme’s Ebola vaccine, which recently showed 100% effectiveness against the deadly virus. With researchers working around the globe in a collective effort to control the virus, there is hope that with greater understanding of its functionality, coupled with the assistance of an effective vaccine, if another Ebola outbreak occurs, the world will not be left defenseless.