Posted on October 29, 2021, 11:46 a.m.
Arizona Center for Investigative Reporting
A new valley fever vaccine for dogs appears to provide a safe and effective defense against the fungal disease that sickens thousands of Arizona pets each year, according to new research by an international team of scientists, and marks an important step which could lead to a similar result. vaccine for humans.
The to study, led by researchers at the University of Arizona Center of Excellence for Valley Fever, was a one-of-a-kind experiment that showed strong protection for dogs injected with two doses of the vaccine. The commercial veterinary version of the vaccine could be available within the next two years, the researchers said.
The findings have important implications for a disease currently on the rise in Arizona and the Southwest. Researchers expect the range of the fungus to spread due to climate change, which makes the need for an approved vaccine all the more urgent. This new study paves the way for further development of the vaccine to potentially prevent infections in humans.
Valley fever is a respiratory disease caused by a fungus of the genus Coccidioids, found in the soil and dust of the Southwest and California. The fungus, responsible for coccidioidomycosis, or Valley fever, most often causes flu-like symptoms such as fever, body aches and cough. In severe cases, when the disease spreads beyond the lungs in what is called disseminated valley fever, the disease can cause life-long debilitating illness and even death.
The disease killed 39 people in Arizona and sickened thousands more in 2019, according to the Arizona Department of Health Services. And so far in 2021, more than 9,000 inhabitants here have been diagnosed with valley fever, accounting for about two-thirds of all cases in the United States
“A veterinary vaccine in and of itself is a huge boon,” said the lead author of the study, Dr Lisa Shubitz, veterinarian and researcher at the Valley Fever Center for Excellence, adding that the new research and the new vaccine “are also a stepping stone for humans.”
The recent study relied on experiments in which 30 dogs were intentionally infected with Coccidioids
in a laboratory. Dogs given two doses of the vaccine were significantly more protected against the fungus than unvaccinated dogs. The researchers also found that the vaccine was ‘well tolerated’, which means that the side effects at the injection site were not serious and that there were no side effects such as fever, pain or vomiting.
Researchers have tried for decades to develop a valley fever vaccine for dogs and humans, but results to date have shown that certain types of vaccines are ineffective and cause severe injection site reactions. It’s not just valley fever: no vaccine approved exists for any fungal disease.
Because valley fever is contracted by inhaling microscopic spores into the lungs, there are few interventions available that can prevent someone from contracting the disease.
Recent AZCIR report revealed
Little is known about who in Arizona is most affected by this deadly pathogen, in part because of the limited state and federal funding allocated to study and mitigate the disease. State policies also limit workers’ compensation claims related to valley fever, making it difficult to track infections, further compounding the general lack of consistent data collected and retained when people are diagnosed. . All this despite research that indicates valley fever is a growing problem in the United States, particularly Arizona, and that the most severe form of the disease, disseminated valley fever, is disproportionately manifested. in people of color.
“They have seen very spectacular protection in dogs and I think that makes it very promising,” said Dr Stuart Levitz, a professor at the University of Massachusetts medical school who was not involved in the study. Levitz, who heads a lab that is working on a vaccine against another type of fungus, said the new study makes him optimistic as it makes progress towards a human vaccine that “would save as many lives as the vaccines we already receive.” “
In Arizona alone, Shubitz said thousands of dogs are diagnosed with valley fever each year. In her veterinary practice, she is “inundated” with sick dogs diagnosed with valley fever. Dogs arrive with symptoms of cough, fatigue and lack of appetite, she said, and sometimes valley fever causes bone damage or even blindness.
“Dogs really do suffer from this disease and their owners’ checkbooks suffer from it,” Shubitz said. She expects dog owners to be eager to get their pets vaccinated, adding that they have helped fund preliminary research through donations and fundraising. This work helped the research team generate enough data to receive a grant from the National Institutes of Health that funded the latest study.
The vaccine being tested in the research is a live attenuated vaccine, which means that it was created from an altered pathogen so that it cannot become infectious or make the host sick. Instead of causing infection, the vaccine gives the immune system the ability to preview the pathogen and better defend itself against future infection.
“This is a live vaccine, so safety is a big issue,” said Dr John Galgiani, co-author of the study and director of the Valley Fever Center for Excellence. There are fears that a live vaccine could make some people or animals sick, but testing in mice without immune systems has still not resulted in illness, he added.
To get the approval from the U.S. Department of Agriculture, which is needed for veterinary vaccines, the next step is to conduct further experiments on dogs with the exact formulation of the vaccine that would be made public, Galgiani said. Researchers work with Life sciences, a pet pharmaceutical company based in Long Beach, Calif., to market the commercial version of the vaccine.
USDA’s approval for a dog vaccine will be a compelling case for funding vaccine development in humans, but the creation and testing of the valley fever vaccine for humans, believes Galgiani, will cost $ 15 million to start and between $ 150 and $ 200 million to finish. “
Federal funding for valley fever research may be difficult to come by, the researchers say, so the organism that causes it remains largely under-researched. The disease is currently classified as an “orphan disease” because there are less than 200,000 cases diagnosed in the United States each year.
Earlier this month, U.S. Representative Kevin McCarthy, R-Calif., Introduced the Act forward
for the third time since 2018. The “Finding Orphan-disease Remedies With Antifungal Research and Development Act” is co-sponsored this session by representatives Tom O’Halleran, D-Ariz., David Schweikert, R-Ariz. and Karen Bass, D-Calif. The bill aims to provide $ 20 million per year for five years through the National Institutes of Health that would be devoted to epidemiologic and clinical research on fungal diseases, including treatments and vaccines for the fever of the valley.
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