News

Ebola and Dogs

According to the World Health Organization, the Ebola Virus has killed more than 3,400 people in West Africa and infected at least twice that many to date. The virus has taken an especially devastating toll in the hardest-hit countries of West Africa; Liberia, Guinea and Sierra Leone. However, infected persons travelling from this region have now spread the disease to Europe and the US, inciting global concern. From a 2005 report, dogs appear to be the first animal species shown to be naturally and asymptomatically infected by Ebola virus, however, there have been no documented reports of dogs either carrying or transmitting the virus. Despite these findings, a pet dog belonging to an infected woman in Spain was recently ordered to be euthanized by the Spanish government against the owner’s wishes. Zoonotic diseases, particularly those transmitted through pets, are concerning to the pet-owning public and the pet care industry as a whole. While media reports may be inflammatory and challenge pet ownership, there have been no scientific reports indicating that Ebola virus has been isolated from, or directly transmitted by dogs. As the virus inevitably spreads into more developed regions, we are likely to see increasing concern and media interest on the role of dogs in the transmission of disease and we should be prepared to respond. This week (Oct 7th, 2014) a nurse in Spain has tested positive for Ebola virus after caring for an infected priest who was flown from the West African region for treatment in a Madrid hospital.  People who were in-contact with this nurse have now been quarantined.   Subsequently, the Madrid regional government obtained a court order to euthanize their pet dog, saying “available scientific information” can’t rule out “a risk of contagion.” The dog has now been euthanized and the alternative of quarantine was not considered. The conflict is that infected dogs are aymptomatic, and it is not known whether or for how long the virus can remain viable in the dog and whether it can be shed into the environment from an infected dog. Sadly, the dog in question was not tested for the virus and it is our view that available technology should allow for testing and quarantine, rather than automatic euthanasia of exposed animals.  It is possible that dogs may harbor the virus, particularly in endemic areas where they may roam and have access to infected animal carcasses; however, house pets that may potentially be exposed in developed countries represent a very different scenario. Precedence should not be set for euthanizing pets as the exposure levels increase and fear escalates. The virus that causes Ebola is not airborne and can only be spread through direct contact with the bodily fluids of an infected person who is showing symptoms or who has died.  To date, the Ebola virus has never been isolated from a dog although seropositivity is consistent with exposure.

Scientific Evidence

Excerpts from;  Ebola Virus Antibody Prevalence in Dogs and Human Risk Loïs Allela,*1 Olivier Bourry,*1 Régis Pouillot,† André Délicat,* Philippe Yaba,* Brice Kumulungui,* Pierre Rouquet,* Jean-Paul Gonzalez,‡ and Eric M. Leroy*‡ Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 11, No. 3, March 2005  
  • During the 2001–2002 outbreak in Gabon, we observed that several dogs were highly exposed to Ebola virus by eating infected dead animals. To examine whether these animals became infected with Ebola virus, we sampled 439 dogs and screened them by Ebola virus–specific immunoglobulin (Ig) G assay, antigen detection, and viral polymerase chain reaction amplification.
  • Among dogs from villages with both infected animal carcasses and human cases, seroprevalence was 31.8%. A significant positive direct association existed between seroprevalence and the distances to the Ebola virus–epidemic area. This study suggests that dogs can be infected by Ebola virus and that the putative infection is asymptomatic.
  • No circulating Ebola antigens or viral DNA sequences (tested by PCR) were detected in either positive or negative serum specimens, and attempts to isolate virus from these samples failed. These findings indicate either old, transient Ebola infection of the tested dogs, or antigenic stimulation.
  • Symptoms did not develop in any of these highly exposed animals during the outbreak, a finding that tends to support antigenic stimulation, asymptomatic, or very mild Ebola virus infection.
  • Although dogs can be asymptomatically infected, they may excrete infectious viral particles in urine, feces, and saliva for a short period before virus clearance, as observed experimentally in other animals. Given the frequency of contact between humans and domestic dogs, canine Ebola infection must be considered as a potential risk factor for human infection and virus spread. Human infection could occur through licking, biting, or grooming.
  • These findings strongly suggest that dogs should be taken into consideration during the management of human Ebola outbreaks.
  • Conclusion:  to confirm the potential human risk of Ebola virus–infected dogs, the mechanisms of viral excretion (i.e. body fluids and virus kinetics of excretion) should be investigated during experimental canine infection. This research would also offer insights into the natural resistance of dogs.
 

Responses from credible scientific organizations

Center for Disease Control (CDC):

“There is one article in the medical literature that discusses the presence of antibodies to Ebola in dogs. Whether that was an accurate test and whether that was relevant we do not know,” CDC Director Tom Frieden. “We have not identified this as a means of transmission,” Frieden added, although scientists do know that Ebola can infect mammals and the virus can spread that way. (1)

American Veterinary Medical Association (AVMA):

Pet dogs and hunting dogs in West Africa have tested positive for the Ebola virus, but they showed no signs of being infected, said Michael San Filippo, senior media relations specialist for the American Veterinary Medical Association. The dogs did not get sick and did not die. There are no documented cases of dogs passing the Ebola virus on to people, Mr. San Filippo said. “There is more concern about fruit bats and non-human primates,” including gorillas, chimpanzees and monkeys. West African people could be infected with Ebola by eating “bush meat,” the flesh of fruit bats and primates infected with Ebola, he said. The association’s statement is confirmed by a study published by the U.S. Centers for Disease Control and Prevention in the agency’s Emerging Infectious Disease Journal. (2)  

Treatments:

There are no approved medications for Ebola. Doctors have tried experimental treatments in some cases, including drugs and blood transfusions from others who have recovered from Ebola.
  • ZMapp, being developed by Mapp Biopharmaceutical Inc., is an experimental treatment, for use with individuals infected with Ebola virus. It has not yet been tested in humans for safety or effectiveness. The product is a combination of three different monoclonal antibodies that bind to the protein of the Ebola virus
  • There are currently no FDA approved vaccines for Ebola. The NIH’s National Institute of Allergy and Infectious Diseases is working on developing an Ebola vaccine. NIH recently announced they are expediting their work and are launching phase 1 clinical trials of an Ebola vaccine.
Further info can be found here:  http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/qa-experimental-treatments.html  

Supporting Links:

  Scientific reference; • wwwnc.cdc.gov/eid/article/11/3/pdfs/04-0981.pdf

Reviews;

Review of Ebola virus infections in domestic animals. Weingartl HM, Nfon C, Kobinger G. Dev Biol (Basel). 2013;135:211-8. doi: 10.1159/000178495. Epub 2013 May 14. Review.   Dead or alive: animal sampling during Ebola hemorrhagic fever outbreaks in humans. Olson SH, Reed P, Cameron KN, Ssebide BJ, Johnson CK, Morse SS, Karesh WB, Mazet JA, Joly DO. Emerg Health Threats J. 2012;5. doi: 10.3402/ehtj.v5i0.9134. Epub 2012 Apr 30.  

Media Reports:

http://tablet.olivesoftware.com/Olive/Tablet/PhiladelphiaInquirer/SharedArticle.aspx?href=PHQP%2F2014%2F10%2F08&id=Ar00101 http://www.petmd.com/blogs/thedailyvet/lorieahuston/2014/august/ebola-virus-and-cats-31940 http://www.post-gazette.com/pets/pet-tales/2014/09/13/Your-dog-can-not-get-ebola/stories/201409130177 http://www.nydailynews.com/life-style/health/questions-answers-dogs-ebola-risks-article-1.1967211   (1) “Press Briefing Transcript.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 8 Oct. 2014. Web. 9 Oct. 2014.http://www.cdc.gov/media/releases/2014/t1007-ebola-confirmed-case.html. (2) Wilson Fuoco, Linda. “Can your dog get ebola? No.” Pets: The animals in our lives.. Pittsburgh Post-Gazette, 13 Sept. 2014. Web. 9 Oct. 2014. http://www.post-gazette.com/pets/pet-tales/2014/09/13/Your-dog-can-not-get-ebola/stories/201409130177.   Source: (http://www.wsava.org/article/ebola-and-dogs)