Protecting your captive born animal from acquiring parasites. What you need to know.

Parasites, What you need to know. 

People read some of these articles and think I bang on a little too much about parasites. Truth is, that's my day job. I majored in parasitology for my degree, and I'm fascinated by them much in the same way that I'm fascinated by snakes. It's a passion of mine to understand the one, to the benefit of the other. 

So naturally I'm aware of some myths in herpetoculture that really aren't servicing us well. This article aims to help you understand the facts so you can protect your animals, and your sanity. 

Lets dig right in: 

You’ll hear it said that:

 “you should always buy captive born because then you wont have to deal with parasites”

“A captive born animal can't have parasites” As in, there is something about their birth location that transfers an immunity to parasites upon captive born animals. 

Or even less fortunate for community morale, “If you were sold an animal as captive born and it later is found to have parasites, the person you bought it from lied to you”. As in, the animal was wild caught and dishonesty from the seller is the only possible explanation. 

None of this is true. 

Parasite Fact to Understand #1- A parasite is a separate living thing from its host. It does not care where the host was born. 

It is true that a captive born animal -at birth- should not have parasites. This is not due to any special immunity that captive animals have though. They simply have not been exposed to any yet.


A wild caught animal is more likely to be exposed to parasites simply by the fact they live in the wild and are more able to be exposed to anything: including predation, road accidents, and yes parasites too. 

So yes, a wild caught animal is waay more likely to harbor a parasite due to their higher risk of exposure- but a parasite needs only to gain access to its host in order to begin the infection process. So don’t assume an animal is immune or must be parasite free based solely on “captive born status”.

Side note for the smarty pants amongst us: Yes, It is true that members of the nematode and fluke classes have been found inside developing eggs before. So an infected mother technically can pass parasites into the ova-- that is true. But! So far, in snakes, none of those infected eggs have been documented to hatch, therefore if it hatched it’s safe to assume it was not actively infected at birth. Moving on. 


Now this part is very important to understanding parasites in order to protect your colony so read it twice. 

Parasite Fact #2- There are many, many, ways for parasites to gain access to their host. 

More myths you might hear are related to host specificity, or transmission.

Transmission Myth: “I keep my wild caught animals separate from my captive born ones so there’s no way my captive born animals could be infected”

Or

Host Specificity myth: “my snake never ate another reptile, bird, whatever and therefore this parasite can’t happen or did happen because of x, y, or z”.


And the like…. 

So lets cover why these are myths: 

Starting with host specificity: That's when someone says something like, “I never fed this animal reptiles so it could not possibly have this parasite” etc. Or this parasite is typically contracted from eating a reptile or amphibian host therefore this infected animal has to have been fed one for it to have caught it.

Nope. All that has to happen was one egg had to be carried from one place to another. While your frog or gecko whatever may have been the most common route, that egg does not care so long as it gets from A to B alive.

A common example you'll see for the transmission route for parasites with an intermediary host goes something like this:  parasites eggs are laid in water, eaten by fish, fish eaten by lizard, that lizard is eaten by a snake and walah. Snake Infection. People get the impression that's the only way it can happen. It's not.

Here’s the thing, in many parasites that snake could have also just drank the water. Or ate the fish. Or a mouse ate that fish and the snake ate the mouse… Very few parasites are actually species specific where they must follow these exact steps. These things more explain typical exposure routes than dictate it-  and that's assuming a wild environment not a captive one, but we’ll get to that.

For funsies, let’s assume the parasite absolutely had to develop in a lizard. Ok that lizard is the one developing the infectious eggs. It’s now pooping out eggs or it dies and its poop or body is eaten by an insect like a cockroach or fly, and that fly lands in a water bowl drank by the snake, or that cockroach eaten by a mouse, then eaten by the snake. Or that anole pooped in the water supply of a rodent farm, those rodents eaten by a snake. Or the cockroach’s poop ends up rubbed against the lip of the snake and it ends up in their mouth. There are just so many, many ways this can happen.

Point is it made it to the snake without the snake ever eating the lizard. So even in parasites that have reptile intermediary hosts, another reptile is not necessarily required to transmit. The egg (or nymph what have you) has to be ingested, but that egg doesn't necessarily have to be inside another reptile's body when it was. This makes sense when you think about it- When your survival is based upon attachment to another animal, the best evolutionary strategies are based on maximizing the opportunity to do so. Diversity is advantageous to parasites, so parasites rarely are that host specific.

Another thing is sometimes people actually are feeding reptiles/fish/birds/worms/etc to their snakes without realizing it too. For example, it is a fairly common practice for people to use scenting liquids to entice their animals to eat. Some common ones are gecko juice and frog juice. This liquid is made of the ground strained whole bodies of geckos or frogs. Should any of those prey items that were ground up to make the juice be infected, and you then baste the rodent in the infected juice and feed it to your snake- welp you've now fed an infected reptile to your snake- without realizing it.

Moral of the story: Its not safe to draw conclusions about your animal’s parasite status based upon a parasite's host specificity. 


Which brings me to the Transmission Myth: “I keep my wild caught animals separate from my captive born ones so there’s no way my captive born animals could be infected”

Nope again. Folks there are quite literally hundreds of thousands of species of parasitic life, and we’re still discovering more. The modes in which a parasite can gain access are quite vast, and parasites evolve to suit their needs same as everything else. Life finds a way. 

Parasites can be transmitted not only via direct contact with the animals poop or mucus membranes but also can be carried via your water, inside your food chain, inside your soil or bedding, by any sort of pest (flies, roaches, spiders) or other parasite (mites etc) that has access to your colony, the list goes on.

There are soil helminths (worms) that are infectious to snakes. Many parasites lay eggs in water and a shared contaminated water can spread infection to an entire colony rapidly. Many, many, parasites are transmitted by eating something else. Most of us are not growing our own rodents. Anything you bring into the room is a new factor and potential source for infection. Shared anything can cross contaminate. Do you use the same tools across different animals? Are you washing their water bowls in the same sink? Does your quarantine and captive room share air conditioning?...

Then there is the super obvious thing all your animals share exposure to, which  of course is *you*. 

You can touch that door knob in your captive colony with something on your hands and then touch something else, likely over and over again after visiting various places like your quarantine room, and now what evers on that knob is now what's in the room…. What else do you touch? your phone you carried in? Or your glasses?  You can go to a show wearing your jacket and hold that pretty house snake and not see the mite that crawled onto your sleeve. Or the worm eggs you just barely didn't coat with the hand sanitizer when you gave it back after it musked you. Did you wash that jacket and every item of clothing you had on after you went to the show? Did you wash, you? Some things are zoonotic (meaning they can infect you).  Have you been parasite tested? 

Do you see my point? 

None of us are running Biosafety Level 4 quarantine rooms out of our houses, and scrubbing down and showering between rooms. So if your quarantine and captive population share anything at all. You have some risk of exposure. 

Don't get me wrong, It is always a good idea to quarantine your animals. I strongly advocate for it. I sure do myself, if I take anything new in. That will *lessen* the risk. But don't make the mistake of assuming you have zero risk. You don't. 

And the last myth: 

“My wild caught snake was given x,y,z dewormer the day it arrived and that treats everything so theres no way this snake has anything.”

Oh lord thats the faultiest one here. This ones not only wrong but dangerous to your snake on top of it. 

There is no such thing as a single dose all in one dewormer for reptiles. Does not exist. You may hear people say, well I gave it a dose of panacur and flagyl so its ‘treated’. NO ITS NOT.  First of all, both of those medications have to be given in multiple doses at specific times to be effective, and that schedule depends on what you're trying to treat, so the only way to know the right course of treatment is to know what you are treating…. So you have to test to know, but by that point you wouldn't be shoving some random medication down its throat- you’d know what they have, if anything, and you'd be treating specifically for that. Ineffective treatments will lead to the parasite coming right back during the next cycle, and worse resistance to the treatment can develop. 

Second, those two meds do NOT treat everything. There are parasites that are entirely unphased by the horse dewormers people get from feed stores and try to give to their reptiles. You're not going to be able to “cover all your bases”. It doesn't work like that. 

Third, Just like in humans, its a really bad idea to go about mixing random medications on the off chance there might be some unknown something there. Drug interactions can occur in snakes too. 

Fourth, treatment has costs on the body too. Unnecessary treatment in a healthy snake can upset gut flora which can create its own problems to avoid a problem you didn't even have. You also might kill your snake in the process of a necessary but untimely treatment. There are some circumstances where deworming treatment needs to be delayed or done in stages to prevent a worse outcome. Some snakes don't have the strength to survive the deworming process and you'll need to solve what's causing that first.

So to recap, “shotgun” treatment- is not treatment. It's built upon nonsense, and it's dangerous. In addition to the potential liver and kidney damage- that snake could very well still have a parasite, and you could spread it by thinking its been "treated". 

By now you're probably thinking, Jeesh April we get it. Were exposed. Thanks for scaring the heck out of us. I'm sorry guys, but I have to. It's the only way to bring about an honest, thorough perspective.

So! If you cant really prevent exposure, what can we do?

Well, if you want to keep live animals you're going to need to assess what level of risk you are comfortable with- and what measures you're willing to take to prevent infection.  

#1 Dont make assumptions.
Remember we’re all exposed to some degree. Even your bestest buddy you've known your whole life and would never sell you an infected animal! - Hey I'm sure he wouldn't- not intentionally. Most people dont mean for stuff like that to happen- but people do not know what is going on *internally* with another creature at all times. It's not reasonable to think they would. But this is one case where what you don't know actually can hurt you, so we must take responsibility for our own veterinary health and do not make assumptions. Instead- get tests. Know. 

Parasite test every single new animal, within days of acquiring it. As soon as possible. This way you can prevent spread and get an idea of how far the infection has progressed for treatment. Knowing how long the animal has been infected can help with things like if anemia is going to be a concern or the potential risk for spread within your colony etc.

Unfortunately, how long the animal has had something is not always something you can pinpoint, but its basically impossible to know if it came from within your colony or from outside it if you delayed the test until significantly later after acquiring it. So do it immediately. Be proactive. Know. 

#2 Take precautions according to your risk comfort level. 

Some will take more precautions than others. That's ok. Weigh the risks and do what's right for you. Here's some things you can do to lessen your risk:

Quarantine and test every new animal. Test any animal with symptoms immediately. Periodically test a random sample animal. Have necropsies performed if an animal dies.

Purchase separate tools and handling equipment, dishes, water jugs, etc for use with quarantined animals. 

Use a hepa air filter in your reptile areas.

Wash the entirety of you, your clothes, etc before entering clean areas and after leaving quarantine areas to avoid contaminating common spaces. Test yourself periodically. 

Freeze all food and scenting supplies for a minimum of 15 days before use (some take even longer). 

If you feed live, you have feed risk even if you raise your own rodents, but you can control variables better if you raise your own. 

Freeze or bake your soil or bedding.

Use disposable dishes like deli cups to prevent contamination from washing things together etc.

Time your contact times with a stopwatch to ensure proper contact time for sanitizers like rescue, f10sc. 

Test your water source.


If you're thinking wow, that's a lot. It is.

Which is why you’ll have to decide what your personal level of comfort is with the risks. None of us are truly at zero risk no matter what we do. All you really can do is prevent what you can, and when that doesn't work look for possible exposure points, address those for the future, and treat those infected.

Truth is parasitism is something that you’ll likely encounter over a long enough period of time in keeping. Whether it’s mites or a nematode or whatever, the odds are very good that one day you'll deal with one of them. That's because life is resilient and diverse, even if inconvenient sometimes. It doesn't mean you're a bad keeper or anyone else is. We can't possibly control everything, as hard as we might try. So be gentle on yourself, and if you have it in you, on others too.

I hope this helps.