dog lovers funding research on vaccines for fungal infections
fungal infections, dogs, and the need for vaccine development
i got here via a 2018-ish article in Scientific America in which dog owners in Southern United States were contributing funding to sponsor research into a vaccine for valley fever. i read it in hard copy, which is why i’m not sharing the link and also why i’m fuzzy on the date. prior to this article, i’d never heard of valley fever, which is endemic in northern mexico and the southern united states, stretching from california to texas. it is projected to reach the US-Canadian border by year 2100.
clover just laying in the dirt. summer 2022.
the number of cases has tripled between 2014 and 2018 and again between 2018 and 2022, according to new research funded by the National Institutes of Health. In the past 20 years, the rate of infection has increased by 800%.
the fungi itself is unique in that unlike most fungi, which eat plants, Coccidiodes immitis can eat animals. its DNA contained genetic markers of a carnivore. is this as horrifying to other people as it is to me? am i the only person who didn’t know fungi could be carnivorous? unlike plants, fungi don’t have chlorophyll, so they have to get their food from the environment around them. they produce chemicals to digest food from their environment, and then absorb the nutrients from that food into their bodies.
whilst we take food from the environment and put it into our bodies to be digested and absorbed, fungi work in reverse: they produce chemicals to digest food in the environment, then absorb it into their bodies.
the fungi itself, Coccidiodes immitis is caused by spores in the dirt that become airborne. the filaments can travel as far as 120 km (75 miles). it’s so infectious that simply driving with your windows down can expose people to valley fever. in an atmosphere like this, animals don’t stand a chance. valley fever has been found in dogs, cats, horses, llamas, alpacas, sea lions, dolphins, and otters. polar bears and kangaroos and wallabies and nonhuman primates at the Phoenix Zoo have been infected.
it’s easy enough to understand how dogs become infected, nose to the ground, snuffling about. while some humans and dogs experience no side effects (asymptomatic), others develop cold-like symptoms, becoming lethargic, developing a hacking cough and drop in appetite, and the development of a fever.
treating it can take as long as eight to ten months. in some areas, as many as 1 in 10 dogs will develop the disease each year. given that up to 30 million dogs will be exposed annually, through habitat or travel, it is not an insignificant number. it has been reported that infection with valley fever is the single most commonly cited reason for surrendering dogs to animal control.
dogs have a higher infection rate than humans and they are also more likely than humans to develop severe lung-blocking forms of valley fever than humans are.
while symptoms are roughly the same, dogs have a higher rate of complications (about 25% of cases vs 1% of human cases). Dissemination of the infection can spread from a lung infection to nearly all tissues of the body, with bone infections being the most common site besides the lungs. Dogs infected with disseminated valley fever can have skin lesions, osteomyelitis, central nervous system disease, and/or pericardial involvement. Involvement of the central nervous system often means that dogs present to their vets with seizures.
through financial donations from hundreds of dog owners, a national institutes of health grant, and commercial assistance from a California company, researcher John Galgiani and his arizona team are testing a vaccine for dogs. the FDA has lower standards for approval for animals than humans, and the vulnerability of dogs to valley fever, makes it an excellent test case that could lead to a vaccine for humans.
the dog version is overseen by the Department of Agriculture, rather than the FDA and would require clinical trials in humans, but if it worked, it could make significant headway in getting ahead of valley fever and provide a model for how to develop and test vaccines for some of the 300 types of fungi that make humans ill.
hurdles have almost been cleared. it is anticipated the two-dose vaccine for dogs could be available in 2024 or 2025. grants have been written requesting funding to trial them in humans. i also want to state that i find it disturbing that it is still acceptable to kill the beagles used as lab dogs in order to determine effects and efficacy of the vaccine, given that we manage to not kill humans during similar RCT trials. i feel like if we really wanted to, we could get important data with the dogs still alive and also accrue longer-term data by testing those dogs a year, two years, three years, etc. after the fact.
as the climate crisis deepens and our world gets increasingly hotter, fungal diseases like valley fever will become endemic in more arid regions. work to develop vaccines to prevent and treatments for have never been more important.
i don’t live in the southern united states, but i have read a lot about how concerned epidemiologists are that fungi will present our next great health hurdle. did you know that a vaccine to protect against fungi has yet to be invented? that’s scary because fungi is everywhere and creates an increased risk of illness for the immunocompromised.
developing new drugs is necessary because existing ones are losing their effectiveness and fungi are adapting and adjusting and learning to do things like, stay alive on surfaces. the good news is that out of an estimated 12 million species, only about 200 are infectious to people.
why isn’t there a vaccine yet? here is where it gets complicated. at the cellular level, fungi cells are a lot more like our cells than bacterial or viral cells are. medications or vaccines that can kill fungi are also more likely to potentially damage our cells. sometime, about 1.5 billion years ago, we had a shared ancestor with fungi. they even breathe in oxygen and breathe out carbon dioxide.
so, while there are currently no vaccines for fungal diseases, it does seem likely that we could manufacture one because infections often create lifelong immunity. that’s the good news. the so-so news is that scientists have been trying since the 1940s to create one. for those of you like me, who remain stuck in perpetual math-land of 2000, that’s 84 years of trying to hit this vaccine home run.
while we’re working on resolving health-related issues, the fungi are working on undoing some of the damage we’ve been doing to our planet. according to one recent study, the myceliar roots sequester 1/3 of the annually emitted carbon dioxide emissions on Earth. the researchers are now investigating how long carbon is stored by the fungi and are seeking to further explore how it boosts ecosystems.
there is room for so much learning. we’ve only barely scratched the surface.
n xx