Ebola Can Live On Cold Surfaces 2 Months, Transmittable 3 Feet Away

The number of confirmed Ebola cases passed the 10,000 mark over the weekend, despite efforts to curb its spread.

And while the disease typically dies on surfaces within hours, research has discovered it can survive for more than seven weeks under certain conditions.

During tests, the UK’s Defence Science and Technology Laboratory (DSTL) found that the Zaire strain will live on samples stored on glass at low temperatures for as long as 50 days. 

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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 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 from the Public Agency of Health in Canada.

Ebola was discovered in 1976 and is a member of the Filoviridae family.

This family includes the Zaire ebolavirus (Zebov), which was first identified in 1976 and is the most virulent; Sudan ebolavirus, (Sebov); Tai Forest ebolavirus; Ebola-Reston (Rebov), and Bundibugyo ebolavirus (Bebov) – the most recent species, discovered in 2008.

HOW LONG DOES EBOLA SURVIVE? 

For their 2010 paper, ‘The survival of filoviruses in liquids, on solid substrates and in a dynamic aerosol’, the UK’s Defence Science and Technology Laboratory (DSTL) tested two particular filoviruses on a variety of surfaces.

These were the Lake Victoria marburgvirus (Marv), and Zaire ebolavirus (Zebov).

Each was placed into guinea pig tissue samples and tested for their ability to survive in different liquids and on different surfaces at different temperatures, over a 50-day period.

When stored at 4° (39°F), by day 26, viruses from three of the samples were successfully extracted; Zebov on the glass sample, and Marv on both glass and plastic.

By day 50, the only sample from which the virus could be recovered was the Zebov from tissue on glass.

For their 2010 paper, ‘The survival of filoviruses in liquids, on solid substrates and in a dynamic aerosol’, Sophie Smither and her colleagues tested two particular filoviruses on a variety of surfaces.

These were the Lake Victoria marburgvirus (Marv), and Zebov.

Each was placed into guinea pig tissue samples and tested for their ability to survive in different liquids, and on different surfaces at different temperatures, over a 50-day period.

When stored at 4° (39°F), by day 26, viruses from three of the samples were successfully extracted; Zebov on the glass sample, and Marv on both glass and plastic.

By day 50, the only sample from which the virus could be recovered was the Zebov from tissue on glass.

‘This study has demonstrated that filoviruses are able to survive and remain infectious, for extended periods when suspended within liquid and dried onto surfaces,’ explained the researchers.

‘Data from this study extend the knowledge on the survival of filoviruses under different conditions and provide a basis with which to inform risk assessments and manage exposure.’

The researchers do stress that these tests were carried out in a controlled lab environment, and not in the real world, but published their findings to highlight the survival rates.

Last week the Centers for Disease Control and Prevention (CDC) updated its Ebola guidelines following the rise in infections.

Filoviruses such as Ebola can survive outside of a host for fifty days on cold surfaces according to a Public Health Agency of Canada (PHAC) document.

According to a PHAC EBOLAVIRUS PATHOGEN SAFETY DATA SHEET posted on the Canadian government agency’s official website, “when dried in tissue culture media onto glass and stored at 4 °C, Zaire ebolavirus survived for over 50 days”. The findings were published in a 2010 paper entitled The survival of filoviruses in liquids, on solid substrates and in a dynamic aerosol.

Four degrees Celsius is equivalent to 39.2 degrees Fahrenheit.

According to a Pub Med abstract of the study posted to the National Institutes of Health (NIH) website, “Our study has shown that Lake Victoria marburgvirus (MARV) and Zaire ebolavirus (ZEBOV) can survive for long periods in different liquid media and can also be recovered from plastic and glass surfaces at low temperatures for over 3 weeks”. The study also noted that the Zaire strain of Ebola “showed significantly better survival within an aerosol”.

Despite these published findings, the current CDC public relations campaign maintains that “Ebola on dry surfaces, such as doorknobs and countertops, can survive for several hours”.

The document posted by the Canada Public Health Agency suggests that the Ebola virus may be hardy enough to survive for almost two months on cold surfaces, at least under laboratory conditions.

Well, at least the CDC is starting to move the narrative’

“Droplet spread,” the agency said, “happens when germs traveling inside droplets that are coughed or sneezed from a sick person enter the eyes, nose, or mouth of another person. Droplets travel short distances, less than 3 feet (1 meter) from one person to another.

“A person might also get infected by touching a surface or object that has germs on it and then touching their mouth or nose.

“Droplet spread diseases include: plague, Ebola.”

The online flyer went on to insist that, no, Ebola is not “airborne,” but it also made clear that, yes, it can certainly be spread through droplets — the manner in which people riding close to each other on, say, a NYC subway or in a cab or Uber ride-share car, or in a bowling alley, might be exposed (Dr. Craig Spencer, the Ebola-infected physician just back from treating patients in West Africa, did all of these things).

“Healthcare providers caring for Ebola patients and the family and friends in close contact with Ebola patients are at the highest risk of getting sick because they may come in contact with infected blood or body fluids of sick patients,” the online informational flyer states.

Some experts are already raising eyebrows of suspicion.

“Well, at least CDC is starting to move the narrative,” said Meryl Nass, M.D., an infectious disease physician, on her blog. “Maybe tomorrow it will be 5 feet. Then 10. Maybe next month they will tell us why all the victims’ possessions are being incinerated and apartments fumigated.

“Just remember: historically, Ebola spread fast in healthcare facilities.”

Spread via aerosol more likely in colder environments?

Dr. Nass had earlier focused on anthrax and the dangers it poses.

Also, in 1995, the U.S. Army’s Medical Research Institute of Infectious Diseases reported in the International Journal of Experimental Pathology (see it here ^[PDF]) that the deadly virus actually spreads faster in colder environs, not the hot, steamy climate in much of Africa [emphasis added]:

We also demonstrated aerosol transmission of Ebola virus at lower temperature and humidity than that normally present in sub-Saharan Africa. Ebola virus sensitivity to the high temperatures and humidity in the thatched, mud, and [wattle] huts shared by infected family members in southern Sudan and northern Zaire may have been a factor limiting aerosol transmission of Ebola virus in the African epidemics. Both elevated temperature and relative humidity (RH) have been shown to reduce the aerosol stability of viruses (Songer 1967). Our experiments were conducted at 24°C [75°F] and [such as Ebola], aerosol transmission is a greater threat in modern hospital or laboratory settings than it is in the natural climatic ranges of viruses.