A British government defense lab finds that Ebola can last up to 50 days in the cold.
The Daily Mail reports [3]:
The UK’s Defence Science and Technology Laboratory (DSTL) found that the Zaire strain [of Ebola] will live on samples stored on glass at low temperatures for as long as 50 days.
The left-hand charts plot survival rates of Zaire strain of Ebola (Zebov) and Lake Victoria marburgvirus (Marv) on glass (a) and plastic (b) at 4° (39°F) over 14 days. The right-hand charts reveal the survival rate under the same conditions over 50 days. Both viruses survived for 26 days, and Ebola was extracted after 50 days.
The tests were initially carried out by researchers from DSTL [4] before the current outbreak, in 2010, but the strain investigated is one of five that is still infecting people globally.
The findings are also quoted in advice [5] from the Public Agency of Health in Canada.
Temperatures of 39°F or colder are common in the U.S., Canada and much of Europe during the winter.
Top Ebola scientists also say that the virus is more likely to be spread by aerosol [6]in cold, dry conditions than in hot, humid weather.
(Given that sneeze droplets can travel 20 feet [7], that’s nothing to sneeze at.)
Indeed, the British defense study cited above also found [4]:
[8]
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All three filoviruses under investigation [Ebola is a type of filovirus] could be detected after 90 min in a dynamic aerosol (Fig. 4a)
In other words – even after 90 minutes – Ebola could survive suspended in aerosols if the temperature is chilly.
The amount of Ebola which survives in aerosol obviously diminishes with time:
[9]
However, since MIT has recently shown that sneeze droplets travel much farther than previously thought – and can enter into ventilation systems [7] – Ebola protocols need to take these realities into account.
This is the first time that Ebola has spread out of West Africa to cooler, dryer nations … so we can’t assume that what works in the hotzone will work here.