Ebola and Enterovirus D68, Pandemic or Panic Part II
October 8, 2014
Recently, fear of infectious disease has become a constant drumbeat on the Internet and television. This is primarily due to two viral diseases. Disease one is the deadly West African Ebola Virus. Disease two is Enterovirus D68. Mike Rothschild did a nice post about the enterovirus on September 16th titled "EV-D68: The (Not) New Disease to (Not) Panic About." Events surrounding these diseases this week seems to have piqued the obsessive interest of the news media: the first-ever case of Ebola diagnosed in the US in Dallas Texas (who was reported as deceased today) and the recent news reports linking the death of a healthy child to the enterovirus. This is part two of my informational posts. This one is focused on the Ebola Virus and the Epidemic in West Africa.
*Warning Technical Jargon!*
The filoviruses, Ebola and Marburg, are among the most virulent pathogens of humans, causing severe disease that resembles fulminant septic shock. The case-fatality rate in the epidemic of Ebola virus in West Africa has been estimated to be approximately 70 percent; rates in earlier outbreaks in Africa (including Marburg virus disease in 2005) reached 80 to 90 percent.
All isolates of Marburg virus are currently considered to be members of a single species. However, there is evidence that they vary in their pathogenicity for humans, since the overall fatality rate in the 1967 outbreak in Europe was 21 percent, whereas mortality among identified cases in 2000 in the Democratic Republic of Congo (DRC) and in 2005 in Angola was in the range of 80 to 90 percent. Alternatively, the striking difference in outcome may reflect the paucity of medical resources where the latter outbreaks took place.
Ebola virus — The genus Ebola virus is divided into five different species (the Zaire, Sudan, Ivory Coast, Bundibugyo, and Reston agents), which differ in their virulence for humans. Since its first recognized appearance in 1976, the Zaire species has caused multiple large outbreaks with mortality rates of 55 to 88 percent.
EPIDEMIOLOGY — The filoviruses were first recognized in 1967, when the inadvertent importation of infected monkeys from Uganda into Germany and Yugoslavia resulted in explosive outbreaks of severe illness among vaccine plant workers who came into direct contact with the animals by killing them, removing their kidneys, or preparing primary cell cultures for polio vaccine production. Since that time, with the exception of a few accidental laboratory infections, all cases of filoviral disease have occurred in sub-Saharan Africa. The frequency of recognized outbreaks has been increasing since 1990. Ebola virus has also been spreading among wild nonhuman primates, apparently as a result of their contact with the unidentified reservoir host. This has contributed to a marked reduction in chimpanzee and gorilla populations and has also triggered human epidemics, presumably due to consumption of sick or dead animals as a source of food.
So you see we have a pretty good idea where the illness originates. There is absolutely no evidence that this is some type of disturbing population control or government plot as some people have suggested... e.g. the Alex Jones show.
The current West African epidemic is by far the largest outbreak of Ebola virus disease ever recorded. It is currently occurring in West Africa with the Zaire species of the virus. Although most previous Ebola outbreaks occurred in Central Africa, this outbreak started in the West African nation of Guinea in late 2013 and was confirmed by the World Health Organization in March 2014. The initial case was a two-year-old child in Guinea who developed fever, vomiting, and black stools, without other evidence of hemorrhage. The outbreak subsequently spread to Liberia, Sierra Leone, Nigeria, and Senegal. Sequence analysis of viruses isolated from patients in Sierra Leone indicates that the epidemic has resulted from sustained person-to-person transmission, without additional introductions from animal reservoirs. The case-fatality rate has been estimated to be approximately 70 percent. Ebola Virus Disease first 9 months of epidemic PubmedThe magnitude of the outbreak, especially in Liberia and Sierra Leone, has probably been underestimated; this is due in part to individuals with Ebola virus disease being cared for outside the hospital setting. As of September 28, 2014, the cumulative number of probable, suspected, and laboratory-confirmed cases attributed to Ebola virus is 7,178, including 3,338 deaths. However, Nigeria and Senegal have not reported any new cases since September 5, 2014, and August 29, 2014, respectively.
On September 30, 2014, the first travel-associated case of Ebola was reported in the United States. An individual who traveled from Liberia to Dallas, Texas first developed clinical findings consistent with Ebola virus disease approximately five days after arriving in the United States. The patient was asymptomatic prior to and during the flight. Initially it was not recognized as Ebola and there are conflicting reports about who knew about his West African travel and when it was know. It was not suspected until his symptoms progressed and he returned to the hospital that sent him home on the first visit. Unfortunately due to complications of the disease he passed away on October 8, 2014. Once this was recognized, proper isolation and quarantine procedures were put in place. It is very likely that he will be the only death directly related to the exposure.
Although this is a deadly and terrifying disease it is much easier to contain than something like influenza, which is airborne. Person-to-person transmission occurs through direct contact of broken skin or unprotected mucous membranes with virus-containing body fluids (e.g. blood, vomit, urine, feces, semen, and probably sweat) from a person who has developed signs and symptoms of illness. This mode of transmission may lead to outbreaks. The most common routes of transmission are as follows:
So should we be very concerned about Ebola spreading to other continents? Will "Patient Zero" spread an uncontrolled infection to the US or Europe? Could it create a widespread outbreak world wide?
If you drift away from speculation and look at the science there is little cause for concern from this epidemic. There are essentially three overall ways to have an uncontrolled outbreak in the western world.
On a personal note: I understand people wanting to quarantine the whole region and be self-serving or protective of themselves. It is easy to fear this disease. While there's no cure and it's deadly and contagious, the disease is just not that easily spread in the western world, which has adequate supplies, medical personnel and sophisticated sanitation/public health measures. We don't need to isolate ourselves. Additionally by quarantining the region completely you will prevent medical personnel from going over to help curb the epidemic. Halting all jet travel (the only way to get there and back) would mean that workers won't go to help since they can't come back. A dedicated few might still go, most will hesitate, thereby critically depriving the area of desperately needed trained medical workers. It will doom thousands to painful death and will worsen the spread of the disease.
So don't be like this ZIDIOT (sic), and see Ebola around every corner. It's not, and it's not likely to be, no matter how bad it gets in Africa.
Disclaimer: This post is my personal opinion, it is not a substitute for medical care. It is for informational purposes only. The information on Skeptoid blog is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. This post does not reflect the opinion of my partners, professional affiliates, or academic affiliations. I have no financial conflicts of interest to disclose.
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