But this latest genome sequencing data pretty much proves some concerning news: the virus may linger undetected, for up to five years, inside a host.
Ebola was -- as an mRNA susceptible virus -- thought to be wholly unlike, say. . . herpes. That is, it was thought to be too fragile to linger inside a human biome, dormant -- only to re-emerge years later.
It looks like that assumption was mistaken, as the virus we face in 2021, seems to have its index case in a health worker/nurse who was in contact with Ebola patients in 2014-15, but never showed symptoms. While it is at least theoretically possible that she independently acquired it from animal to human transmission (by eating tainted bush meat, for example), it would be unlikely to be such a close genetic match (if it had traveled by that separate path), unless it was from human to human, and. . . of the 2014 version. And that means we must either expect to face sporadic re-emergence over decades, perhaps -- or decide to spend vast resources to use therapeutics to clear the viral load from all contacts of contacts. That is geometrically more resource intensive than a two dose vaccine.
Here's the latest, from Science, this morning:
. . .The virus causing the new outbreak barely differs from the strain seen 5 to 6 years ago, genomic analyses by three independent research groups have shown, suggesting the virus lay dormant in a survivor of the epidemic all that time. “This is pretty shocking,” says virologist Angela Rasmussen of Georgetown University. “Ebolaviruses aren’t herpesviruses” -- which are known to cause long-lasting infections -- “and generally RNA viruses don’t just hang around not replicating at all.”
Scientists knew the Ebola virus can persist for a long time in the human body; a resurgence in Guinea in 2016 originated from a survivor who shed the virus in his semen more than 500 days after his infection and infected a partner through sexual intercourse. “But to have a new outbreak start from latent infection 5 years after the end of an epidemic is scary and new,” says Eric Delaporte, an infectious disease physician at the University of Montpellier who has studied Ebola survivors and is a member of one of the three teams. . . .
This obviously is a much larger policy question: how much do we, collectively spend, to eradicate it -- if vaccines are cheaper and effective? And that's in relatively far off Africa. What if I told you that COVID-19 looks to be very much like Ebola, in its mRNA susceptible mechanics? What then should we be thinking about that admittedly far less lethal, but far more prevalent scourge, now -- globally? These are likely to be the debates of the next five to ten years, in/at pandemic eradication sciences conferences.
This is also why I find life sciences problems so. . . ever intriguing: life -- even viral life, finds a way. Not in the sentient sense, but in the idea that over billions of generations, random mutations confer survival advantages, to a select few -- and those few. . . become the dominant many, by replicating in overwhelming numbers. Smile. . . .
नमस्ते
No comments:
Post a Comment