Does UVB Prevent Viral Respiratory Infections in Reptiles?
We’re going to jump right back into viral respiratory infections in pet snakes with nidovirus being the most pervasive virus medicine has identified with respiratory disease in pet snakes. There were lots of great questions from the last article.
Nidovirus, the Nidoking of Viral Respiratory Disease
We have to clarify nidovirus because of the desire to conflate this term. In the context of pet snakes when we say nidovirus we are not talking about the entire family of nidoviruses that includes white bream virus… because that affects fish. Fish are irrelevant to this conversation. Nidovirus, generically, is a colloquial way within the context of reptiles to refer to viruses that are nidoviruses that also affect reptiles. Recently these have been referred to as serpentoviruses and include viruses named after species they were isolated from: ball python nidovirus, morelia nidovirus, etc. Even more recently similar viruses were isolated from veiled chameleons.
Serpentovirus is the more correct term for snakes but we’re going to continue to refer to it as nidovirus. It should be really obvious that the fish are irrelevant when speaking about pet snakes.
How Nidovirus Persists
Snakes infected with nidovirus do not recover. They remain contagious. Some snakes can have no symptoms and still transmit the virus for years. Fishhead Labs has a green tree python they have kept for more than 4 years who does not show any clinical symptoms but continues to throw high viral loads when tested.
From self proclaimed ethical, rational, science backed keepers to communities using racks and shunning UV there is one unifying factor across the aisle: “My snakes don’t get sick and I don’t need a testing regimen because my husbandry is too good” or, in a best case scenario, “I tested one time and just know”.
Nidovirus is transferred by respiratory droplets. Snakes throw their tongues out to catch particles in the air and deposit those particles exactly where the virus wants to be. In reverse they throw those particles out while using the same mechanism.
We’re going to dispel some myths while we’re here. While improper husbandry may increase the chances of viral transmission it is not the cause of viral transmission. It should be abundantly clear that viruses are the cause of viral transmission. This is something we bring into the environment of these animals.
We control the environments for these animals. They do not have little king snake jobs and have to go ride the train. They do not have social dates without us. We are completely responsible for what enters and leaves their environment — that includes viruses. Make sure you understand that correctly when I say we are responsible for what enters and what leaves our environments.
From ethical rational science backed keepers to communities using racks there is one unifying factor across the aisle: “My snakes don’t get sick and I don’t need a testing regimen because my husbandry is too good” or, in a best case scenario, “I tested one time and just know”.
Screening (Diagnostics, Testing)
Screening is how we control what viruses enter and leave our environments. Testing, specifically PCR testing, is the forefront of any disease mitigation. Hygiene is extraordinarily helpful in reducing the transfer of infectious material. Quarantine is critical but not as clear as people suggest.
Dr. Robert J. Ossiboff has recommended 1 year of quarantine with a testing regimen. To mention Fishhead Labs’ green tree python again, there are certainly animals that would blow right past this quarantine with the virus. There is no replacement for testing.
We’ve established that nidovirus is not as obvious as people attempt to make it out to be. It can zoom right through a 30 day quarantine easily. It is critical to keep our hygiene standards up throughout the duration of quarantine that, in at least one exceptional case, would be irrelevant.
Animals should be screened throughout life events. Shipping is a great time to test. Breeding is a great time to test. Any time you plan to introduce two reptiles into the same room would be a great time to test. Saturday would be a great time to test.
With all of this established let’s jump into UV light.
UV Light
There are many reasons to offer the complete spectrum of UV light, beneficial for many reasons, to your animals. We’ll have to stop for a moment and remind people of context: when I say “whole spectrum” I mean UVA and UVB light produced by reptile lighting products. I do not mean dangerous UVC light. That would not be beneficial.
You can use UV light (the whole spectrum that we offer to animals) for a variety of reasons. Controlling viral respiratory disease in reptiles is probably not one.
The effectiveness of the whole spectrum of UV we offer to these animals at the power level and distance, as well as a proper gradient, makes assuming they have any ability to destroy these viruses in-situ unknown. The overall dosage of vitamin D, if unmeasured by blood test, is unknown. Coloration, age, body condition, total fat within body mass, and many other factors control vitamin D synthesis.
While we have studies and speculation about bolus delivered vitamin D (that is through dietary supplementation — pills) possibly reducing the effects of or even possibly reducing the transmission of respiratory disease the method of delivery and effects are unknown and unconfirmed in pet reptiles. Vitamin D delivered this way can be toxic above certain thresholds to many pet reptiles.
Screening is known to be effective. It is more effective than taking a chance with your hygiene regimen as the only method for disease control. It is more effective than quarantine. It is infinitely more effective than the speculation around UV and vitamin D.
UV light is irrelevant to the control of viral respiratory disease in reptiles. We have superior methods that this cannot replace. When used in combination with superior methods, screening, it is entirely obsoleted by the use of screening.
You can use UV light (the whole spectrum that we offer to animals) for a variety of reasons. Controlling viral respiratory disease in reptiles is probably not one as it is the weakest mitigation strategy we have.
Adenovirus and UV
To jump a little out of scope let’s look at adenovirus. This is a pervasive virus in bearded dragons. Like nidovirus, this disease can very easily go undetected and blow through quarantines with ease. Bearded Dragons are one species that the overall hobby of keeping reptiles doses with high loads of UV light to specifically prevent metabolic bone disease (MBD).
Adenovirus is still pervasive in spite of consistent UV exposure for captive animals.
Why is there a bearded dragon in the middle of an article about viral infections for snakes? Because people sent me MBD reports in bearded dragons in response to snake viral respiratory disease. It doesn’t make sense to me, either, but we’ll give them a bearded dragon.
Disease Mitigation or Prevention or Cure or Whatever You Like
The only effective method we have for disease prevention or mitigation is screening. When screening it is often not good enough to simply do one test and then celebrate your freedom. Multiple tests are required for both adenovirus and nidovirus when bringing animals into or out of a collection.
These viruses, even when not accompanied with disease (read: symptoms), can still be transmitted and are still causing systemic damage inside of these animals independent of UV exposure. Adenovirus and nidovirus will both shorten the lifespan and create additional complications in the health of the animal. This is the same with viruses that affect humans.
These viruses are extremely dangerous. No rational person should believe anything other than testing would lead to disease management. The risk is too high, the tests are cheap, and there is no reward. Disinformation persists, of course, especially in our current environment of a human pandemic.
Humans, of course, are an entirely different difficulty for disease control. Animals, especially reptiles that we keep in controlled environments mostly isolated from others, are not. In either case the role of vitamin D in preventing disease is not clear and is ineffective when compared to standard testing.
This is exactly why major medical organizations will not tell you that vitamin D will prevent viral respiratory disease.
This is exactly why UV is completely irrelevant to preventing, managing, or mitigating viral respiratory disease in pet snakes.
This is exactly why Dr. John Campbell, a proponent of vitamin D and referenced repeatedly to support speculation, will tell you in his series of videos exploring the subject repeatedly that individuals should seek appropriate testing.
These viruses are extremely dangerous. No rational person should believe anything other than testing would lead to disease management barring vaccines, therapies, or other proven medicine being developed. The risk is too high, the tests are cheap, and there is no reward for attempting anything else. Disinformation persists, of course, especially in our current environment of a human pandemic. Diagnostics (testing) is the universal message from the field of both human and animal medicine. “Bad husbandry causes viruses” is the flat, ridiculous, and useless message from amateur, inexperienced keepers posing as researchers and ultimately detracting from science.
The End of the Subject…?
Disease control, which is integral to husbandry and welfare, is rarely discussed in meaningful ways. The correlation between human studies with bolus vitamin D and a UV lamp causing the synthesis of unknown vitamin D levels in an animal is not an equal comparison. Health organizations have not published that vitamin D is an effective prevention against viral respiratory disease. Even if, or possibly when, we do find a correlation between vitamin D and reduced transmission it will still be irrelevant: the primary method for reducing viral disease transmission will still be a testing regimen leading to quarantine and proper hygiene for and around the affected.
Find a licensed veterinarian that I can quote in the capacity of veterinary medicine that says otherwise. Talk to your veterinarian. If you can’t find one to talk to and would like to participate in modern science including testing you may find these links helpful:
VetDNA (Research Associates Laboratory)
Laboklin (Germany, English Site)