In February, an outbreak of Ebola in Guinea began. As of last week, there were at least 80 infections and 59 deaths. Hitting closer to home, there was speculation that a man who had taken ill in Saskatchewan after a recent trip to western Africa may have contracted Ebola on his travels. He has since been cleared, but it certainly sends a message that like SARS in 2003, worldwide travel has the potential to bring pathogens - often deadly ones - to geographical areas they are not native to.
Ebola hemorrhagic fever with its often fatal outcome is by far one of the scariest known human pathogens due to its fatality rate of approximately 83%. Discovered in Zaire (now the Democratic Republic of the Congo) in 1976 there have now been 5 species of Ebolaviruses identified, with 4 of the 5 virus species causing illness to humans. Unfortunately, the reservoir host for Ebolaviruses has yet to be found. Researchers believe the virus is zoonotic in nature and bats are the most likely culprit.
From a virology perspective, Ebola is an enveloped virus that can be transmitted via direct contact with blood or secretions of an infected person, and exposure to fomites that have been contaminated with infected secretions. Symptoms may appear anywhere from 2 to 21 days after exposure to Ebolavirus, though 8-10 days is most common. Symptoms characterizing Ebola are unspecific in the first few days of the infection, making the virus even more dangerous. Infection is marked by initial signs of fever, fatigue, exhaustion, muscle aches, and dizziness. As the disease progresses bleeding under the skin, in internal organs, and from the eyes, ears, and mouth are seen. Patients with severe progressions of the disease express symptoms of shock, delirium, coma, seizures, and nervous system malfunction.
As highlighted by past outbreaks, Ebola can spread easily through household contacts (families and friends) because of close contact with infectious secretions while caring for the ill. Likewise within healthcare settings the virus can spread rapidly, particularly if hospital staff are not wearing the appropriate PPE (masks, gowns and gloves). Cleaning and disinfection of fomites and medical equipment is an important part of minimizing transmission.
I have to chuckle, because as I write this blog, I am sitting in a plane on a trip back from Des Moines, Iowa via Chicago. The fact that worldwide travel (okay, North American for me) can be accomplished in a matter of days really hits home! We just truly never know when an infected person, or contaminated food or object may be on its way to spread disease to unsuspecting populations! Since my introduction to the idea of outbreaks almost 30 years ago, my interest has never waned. I'm curious to learn what the next 10 years has in store!