An unfortunate result from RAL testing. Arenavirus positive result

Not a result anyone wants to see but I’ve received a positive arenavirus result from RAL labs. I would like to hear input from the community as I’m a bit torn on what to do with the result?

The positive result was my VPI Jungle girl, Jewel. I tested for a few reasons but mostly for peace of mind and potentially breeding next season. With that in mind I tested her and my male, Ink. Ink shows negative results for the boid panel, so that is a major relief. Needless to say I suspect Jewel’s sister sibling will test positive as well.

I hope to test the rest of my collection today and have results tomorrow. I feel like that might give me some insight on how I will be approaching this. I’m very glad I’ve practiced strict sanitation between animals and keeping dedicated tubs/enclosures/bowls per animal. I know I’m mite free. The only thing that has me sweating are mosquitoes. I’ve never seen one in an enclosure but we do get them around this time of year. As silly as I might look, I may add mosquito netting to my racks and enclosure vents/glass for the time being. Move my bug zapper in there too.

Pending the results of the rest of my collection, I’m not sure what I’ll do? If it’s just Jewel and Blush I’ll most likely look to re-home with full disclosure and RAL results. This would be to protect the other 9. If majority are infected, well then I may just re home the negatives and keep an arena positive collection. I don’t have the space for both unfortunately.

Not sure on the correct way to proceed here? I don’t want to euthanize an animal that’s eating, that’s for sure. I also don’t want to pass it along full disclosure and have someone ignore that information and breed them either?

Thanks for any input.


Before anything else, I’d retest. There are false positives.


@smite I agree with @sonjakreptiles. You should definitely get her retested, just to make sure.


I second this as well Matt. Both of your plans are solid either way.


Both of these are good plans. But what would you rather do?


I appreciate that guys but didn’t see this before dropping off my tests. Hats off to my wife for helping me swab 7 more.

While I didn’t swab Jewel again I did sample Blush. That might give me a hint as to the accuracy. Either way, I’ll be testing again on any positives.

I appreciate the input. Good to know there can be a false positive. If a retest shows negative then maybe I’ll go with a blood sample to the university of Florida. Jewels and Blush’s build do seem a bit different than my previous boas that got larger than them. One of the other reasons I sent out the test.

I gotta say I have a sweetheart of a collection, not a single tag or attempt from the whole group


I’d prefer not to have arena in my collection. It would have to be a large number of my group turning up positive for me to go the second route. Hopefully tomorrows results makes the decision easier for me with that in mind.
I didn’t have all swabs on hand but 7 will give me a really good idea. I have 2 pairs of siblings so I tested one of each out of them. I know anyone of them came have it but with the rest coming from reputable people (not that they necessarily test) gives me a bit of hope it’s just the two.


A few shots from yesterday before I tested her. I feel like her back 3rd is a bit skinny, through the tail in comparison to her mid section.


If you read the scientific literature, it is apparent that reptarenavirus is almost endemic in boas. There is decent evidence that presence of the virus is not and absolute sign of disease state. There is also some evidence that co-infection of multiple, distinct strains of the virus may be contributory to disease state

A recent article:

Important notations from the article:

  • snakes can harbor reptarenaviruses without showing IBs [inclusion bodies]
  • snakes with BIBD [Boid Inclusion Body Disease] commonly carry a swarm of reptarenavirus segments
  • S segment RNA level to positively correlate with the presence of IBs (in English - the higher the amount of S segment, the greater the likelihood of IBs and, subsequently, development of BIBD)
  • data suggest that some animals might be able to clear the infection or at least exhibit transient or intermittent viremia

I never advocate for a complete ‘slash and burn’ in these cases (I know you are not talking about that, but I have seen it done numerous times by others when they get a single reptarenavirus or serpentovirus-positive animal and so this has become a standard reply from me)

I do advocate for isolation of known positive animals for observation. So long as they are not showing morbidity, then they are likely able to live healthy and happy lives. Continued monitoring of those animals (and your rest of the collection) is advisable to monitor for viral status.

I am not familiar with RAL’s specific target, but if you can talk with them and get clarification on it and the actual Ct value, it can also help inform you of the direction you may need to look at (for reference, the lower the Ct value the higher the viral titer and, if their target is the S segment, therefore the higher the likelihood of IBs and thus development of BIBD)


I really appreciate this informative response! I’ve come up with a temporary plan for isolation of positive animals, or if a large number, negative. whichever is smaller will get moved to a different location.

I’ve started to read through that article, thank you for the link. It’s all pretty new to me so I’m going to need to re-read that a few times to start to understand it, so thank you for the breakdown key points.

I’ve sent an email to RAL asking what their specific target is in the RNA genome, small or large. I’ve also asked if they can provide me with a Ct value so I can try to get a better idea of the viral load. Hopefully they are targeting the S segment so I can have a little more insight into the likely hood of BIBD developing. They do show it as arenavirus (IBD) on their BOID panel, so hopefully that’s the case.


Out of the 9 I tested only Jewel has tested positive for arenavirus. Blush, Jewel’s sibling, did not test positive. I found that interesting. I’ll be retesting Jewel and Blush again, to be sure.

If I can find herp specific vet locally that will draw blood for UOF test, I’ll probably do that to get a more concrete answer. I’ll probably do a fecal on her and Blush at that time as well.


Hi, most people who keep boas, and do any testing will feel your pain at some point.

Just wanted to toss out there that even 2 “positive” parents doesn’t mean the babies will show up positive.

The more you look into it, and the more people you ask, you’ll probably come to realize we know way less about this than we know. lol


Please let us know how it turns out.


Will do @lumpy.

I hear ya @taylor-s. The more I read around the more varied opinions I find on it. Everyone is due to eat, I’m gonna feed and retest later next week.

I appreciate everyones feedback, this is truly a great community.




Unfortunately its near impossible to have an arena free collection once you get past 10 or 15 snakes. Ive seen time and time again people test their perfectly fine collection and find a few, or many positives.

The real bummer is, you really have to test every year to keep up the negative statuses. Ive seen snakes switch from negative to positive after 3 years of negative testing. Idk if it has anything to do with age bringing the Inclusions to the forfront or if its the testing being flawed.

Its best just to do what ever youre most comfortable with. Owning boas, arena may just be something we have to live with and I do not say that lightly.


The herp keepers best friend:

It is very well documented that reptarenaviruses can be vertically transmitted. Yes, that does not guarantee all babies will get it, but it is a very real risk

As a clarification, the test is not for the inclusion bodies but for the presence of the virus itself.

As far as the test being flawed, there are no 100% accurate 100% of the time tests - that is just the way of the world - that said, I have to assume RAL, being a veterinary diagnostic lab, is under some level of ISO protocol which mandates a high level of accuracy and repeatability. Working in a ISO lab myself, I can say that, for us, even a 1% false positive rate is unacceptable. So odds are that animals suddenly testing positive after years is not a problem with the test but something to do with the nature of the virus itself. Likely what is happening is something like we see with VZV and shingles (and all the other herpesviruses in fact) where virus is present but quiescent in the animal and then something causes it to enter a more active state and begin replicating and therefore able to be picked up by the test


Thanks for that insight Matt. My original breeding plan was to test the pair I plan to pair for the upcoming season. My plan was one test around now, when I was going to start increasing food, then maybe a month before introduction of the pair. If Nido and Ophidian show negative on the next boid panel tests, I’ll just start testing for arena. That cost wouldn’t be horrific every year or so and it’d be interesting to see how things develop.

@taylor-s I think part of what you were getting at is I shouldn’t rule out the two untested siblings for being arena free. I plan to get samples from them when I retest Jewel and Blush to be sure.

Here is the response to specific targeting and Ct levels.
“We do target a specific portion of the rna. All our reactions are probe based so all of our regions are quite specific. Ct values will not help you much with this as they are highly dependent on the sample submitted. To understand the sensitivity of each reaction you would have to make an assumption or know the quantity and quality of target organism. For this reason we do not send our cts out. Viral load and ct values only correlate in regards to samples with the same initial loading.”


Thanks for the vet link as well, looks like I have a good one not too far away.


Not an unanticipated answer, but also one that is not entirely accurate.

One of these days I really should get around to chatting with them, but I would really need a “friendly introduction” from a mutual so that the conversation could immediately begin at the peer level rather than the tedious ‘prove you are smart enough’ level


Ive personally used the University of Floridas blood tests, PCR and QPCR after they know what strain to look for. Results are still all over the place and ral has been too.