In recent days, several politically charged news stories and social media posts have surfaced in regards to infectious disease research conducted in dogs. Sadly, in many instances, incorrect, incomplete and/or misleading information is being circulated, leading to significant public confusion. Americans for Medical Progress has constructed the following Q&A in order to provide accurate answers to some of the most common questions that have been raised.  

What is this all about?

Recent news stories and social media posts have focused on a small collection of studies to combat two separate tropical diseases. Each of these serious diseases threaten both human and animal health. One disease that is being studied is called leishmaniasis. The other is called lymphatic filariasis. 

What is leishmaniasis? 

Leishmaniasis is caused by a microscopic parasite named Leishmania infantum. Symptoms for infected patients might include skin sores, fever and the swelling of internal organs. In severe cases, the condition can be fatal. According to the Centers for Disease Control and Prevention, leishmaniasis infections can be found in approximately 90 countries throughout the tropics, subtropics and southern Europe. In Northern Africa, where the disease is commonly found, leishmaniasis mainly impacts children under the age of five. Leishmaniasis also poses a threat to U.S. troops and other personnel, as well as U.S. military dogs, living in areas where the disease is endemic. 

Leishmaniasis is spread by sand flies which serve as the vector (or mode of transportation) for the Leishmania infantum parasite. Domesticated dogs often serve as a natural reservoir for the disease, meaning that human infections can occur when the parasite is passed from infected dogs to humans via sand fly bites.  

What is lymphatic filariasis?

The second disease referenced in recent news stories and social media posts is lymphatic filariasis (LF), also known as elephantiasis.    

Like leishmaniasis, LF is also caused by a parasite transmitted by insects. In this case, the parasite is spread by mosquitos. It is a dangerous, worm-like organism that can cause disease in both humans and dogs. It is the second leading cause of human disability in impacted countries. Those who are disfigured are frequently unable to work because of their disability. 

Can these diseases be prevented with vaccines?

No approved vaccine currently exists to prevent leishmaniasis or lymphatic filariasis infections. However, efforts to develop vaccines to protect both humans and dogs are underway. A brief summary of some of this research can be found below.   

Why must dogs be studied for leishmaniasis research?

Dogs are involved in leishmaniasis research because they are a natural reservoir for the disease. The parasite also threatens the health of dogs. The Leishmania infantum parasite often spreads when a sand fly first bites an infected dog followed by a human. The presence of parasite-infected dogs allows the disease to persist and infect additional humans and animals.  

Why must dogs be studied for lymphatic filariasis research?

As mentioned previously, the parasite behind LF can cause serious disease in both humans and dogs. As a result, both species benefit from animal-based studies. 

What is the purpose of the research mentioned in news stories and social media posts?

Recent news stories and social media posts focus on a combination of three research projects attempting to combat both leishmaniasis and lymphatic filariasis. Two of these studies were supported by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. However, the third was not.

In one study – leishmaniasis research that has incorrectly been attributed to the National Institute of Allergy and Infectious Diseases – scientists were seeking to better understand how the Leishmania infantum bacteria is transmitted between dogs and humans. This information can now be used to develop strategies to prevent parasitic infections in both humans and animals, better control the disease in impacted species, prevent disease-related disabilities and save lives. 

A second study – which was financially supported by the NIAID – is assisting in the development of a leishmaniasis vaccine aimed at preventing disease in both dogs and humans. In this NIAID-study, twelve dogs were immunized with an experimental vaccine at the Pasteur Institute of Tunis. The dogs were then let out in an enclosed open space during the day, during sand fly season in an area of Tunisia where canine leishmaniasis can be commonly found. The goal of the research was to determine if the experimental vaccine prevented the dogs from becoming infected in a natural setting. Because leishmaniasis is commonly transmitted from dogs to humans and because the disease threatens the health of dogs, canines were logically necessary for this research aimed at reducing the spread of this serious disease. At the same time, the project was designed to ensure the involved animals experienced no discomfort.

The third research project is aimed at combating lymphatic filariasis. That study took place at the University of Georgia and it was also supported by the NIAID. This research focuses on a vaccine candidate which could potentially be used to prevent lymphatic filariasis in humans, as well as other parasitic infections, including heartworm, in dogs. Because lymphatic filariasis infections pose serious risks to both humans and dogs, studies in canines are both logical and necessary.     

Did the National Institute of Allergy and Infectious Diseases fund the research shown in images being distributed by news outlets and social media posts      

No. The images of beagles in several news stories and social media posts were taken from an article published by the medical journal PLOS Neglected Tropical Diseases in July 2021. However, the manuscript mistakenly stated that financial support for the research had been provided by the National Institutes of Health. Neither the NIAID nor any other institute within the NIH supported this specific research project.  

Here’s a link to a correction posted by the journal. A screenshot of the statement can be found below.  

Question: Do dogs involved in research frequently have their vocal cords removed? 

A vocal cordectomy, also known as debarking or bark softening, is occasionally performed on dogs living in either a home or research setting. It is a surgical procedure, performed by a veterinarian on an anesthetized animal, where tissue is removed from the vocal cords to permanently reduce the volume of its vocalizations. The surgery does not hurt the animals. In research settings, it may be used where numerous dogs are present. This procedure is done to reduce noise, which is not only stressful to the animals but can also reach decibel levels that exceed OSHA allowable limits for people and can lead to hearing loss.

Question: When it comes to animal research in the United States, are there any regulations or policies in place to ensure the animals are well cared for?  

There are extensive regulations and measures in place in the United States to ensure the ethical treatment of animals involved in health research. These include, but are not limited to: a large collection of animal welfare laws known as the Animal Welfare Act, USDA oversight via unannounced inspections of research facilities, strict guidelines for federally funded research, onsite veterinary oversight and frequent accreditation requirements.  

In specific regard to NIH-funded research, animals are protected by laws, regulations and policies to ensure the smallest possible number of subjects and the greatest commitment to their welfare. Institutions that receive research funds, including those located in other countries, must conduct animal-involved studies in accordance with the Public Health Service Policy on the Humane Care and Use of Laboratory Animals. The proposed use of animals in research is evaluated during peer review for both contract and grant proposals and animals used in research are to be provided with appropriate anesthesia and veterinary care. The principles for what is — and is not — allowed are governed both by regulations administered by the NIH Office of Laboratory Animal Welfare and the grantee institution’s animal care and use committee (IACUC)

Sources: 

• Centers for Disease Control and Prevention
• World Health Organization 
• National Institute of Allergy and Infectious Diseases