November 06, 2014
Some water utilities have begun receiving inquiries regarding Ebola. Below are a few facts and resources to reinforce that Ebola cannot spread through the water supply.
The Ebola virus causes an acute illness that is often fatal with a death rate of up to 90%. Ebola virus disease first appeared in 1976 in two simultaneous outbreaks, one in a remote area of Sudan and the other in a village near the Ebola River in the Democratic Republic of Congo, from which the disease takes its name. The current outbreak in West Africa (the first cases reported in March 2014) is the largest and most complex Ebola outbreak since the Ebola virus was first discovered.1 The current outbreak has spread through both urban and rural areas.2
Ebola is not a foodborne, waterborne, or airborne illness. The virus is transmitted to humans from wild animals and spreads in the human population through humanto-human transmission. Ebola is transmitted through direct contact with infected bodily fluids (e.g., blood, vomit, feces).1,3 The Ebola virus can only replicate within host cells. Therefore, it cannot survive long in water because it does not have its host — either a human or an animal. Because of Ebola’s fragility when separated from its host, bodily fluids flushed by an infected person would not contaminate the water supply.4,5 Researchers believe that Ebola survives in water for only a matter of minutes. This is because water does not provide the same environment as our bodily fluids, which have higher salt concentrations. Once in water, the virus will take in water in an attempt to equalize the osmotic pressure, causing the cells to swell and burst, thus killing the virus.
1 World Health Organization (WHO)
2 World Health Organization (WHO)
3 Centers for Disease Control and Prevention
From the CNN interview cited in the WRF statement:
Would any bodily fluids this patient flushed contaminate the water system?
The virus wouldn’t survive long in water, [virologist] Jean-Paul Gonzalez at Metabiota, a company that tracks global infectious diseases, told NPR. The virus depends heavily, he said, on its host — either a human or animal — to stay active.
U.S. sanitary sewers and our waste water treatment system will kill the virus, Tumpey agrees. “There’s no concern there.”
From the NPR interview cited in the WRF statement:
Can Ebola be spread through a drop of water or carried through the water system?
“[The virus] will not remain for a long time in the water,” Gonzalez says. “It’s not a very rich medium to protect the virus.”
It’s important, he adds, to remember that viruses aren’t as resistant outside the body as bacteria are. Rather, they depend heavily on the cells of their host — animal or human — for survival.
In water, the Ebola virus would be deactivated in a matter of minutes, Schmaljohn says. That’s because each Ebola virus is encased in an envelope taken from the outer surface, or membrane, of a host cell.
So what about cells in water that are infected with Ebola? Could you get the virus from infected cells in contaminated water?
Infected cells don’t live long inside a liquid that doesn’t have the same salt concentration as in our bodily fluids.
Drinking water has a lower salt concentration than that found inside human cells. As water rushes inside the cell to balance the salt concentration, pressure builds ups. Eventually the cell bursts, killing the virus in the process.