How to get rid of mite infestation in C elegans lab?

Hi All!
Can you please help us if you have any experience with mite infestations? How can we get rid of those 8-legged beasts?
We EVEN see them on our clean plates, before we put the worms on them. We don’t know the source of contamination at this point. We are trying to find that one first. Do you have any suggestions as to what the possible sources can be?
Thank you very much in advance!


there are a few ideas in this old posting to (follow the thread);



We had an infestation of late and that post was helpful. We used the anti-mite paper, which you can now get on Amazon (

That was used to protect area where we stored plates. If you have programmable incubators, those can be cleaned by heating to 55ºC-60ºC. I put an infested plate in the incubator at 60ºC and mites were dead in 45 min. I left the incubators 36 hours to be sure. Get a magnifying glass and look throughout your bench to see if you can identify the source. Spray down your bench with ethanol frequently and repeat all of the above diligently. These infestations are easy to take care of if caught early, but quickly spiral out of control.

Good luck!

Bleaching the incubators and space you pour/seed plates is also effective. If you have a fly lab near you, that could be the source of the mite infestation. You could find out if they are having some trouble with mites. If they don’t control it you could continue having problems.

steve v

Cleaning things with ethanol is always good practice, but be warned: if you rinse a mite in ethanol, you get a clean mite, and possibly a drunk mite, but not a dead mite. I haven’t tested mite eggs with bleach, but if they’re anything like worm eggs a little bleach might not do the job, and I’d strongly doubt ethanol would affect the eggs.

Baking your incubators is good, though it’s very likely people will subsequently reintroduce mites.

Flame works, with all the obvious risks. I recommend cleaning thoroughly, flaming as much of the area as you safely can, and subsequently keeping your workspace clean and current - in my experience, mites tend to congregate in focused infestations and not to disperse widely or rapidly; one plate in a stack may have dozens of mites while the others have none. Mites don’t reproduce any faster than worms, so even if you can’t eradicate them you can keep a benchtop infestation under tight control, by keeping things tidy and watching any plates that have been left lying around for too long.

Mites can definitely survive in ethanol (I know). Try it yourself, take a mite infested plate and fill it with either 70% OR 100% EtOH. The worms all die and the mites live on.

To tackle a serious mite problem think nukes not surgical strikes. This requires a comprehensive lab wide clean up where everyone follows suit. It takes just one slob to ruin a lot of hard work.

  1. Clean incubators. Remove all worms/plates/boxes from incubator. Heat to 60C o/n with moth balls in the incubator. If there are any old spills in the incubator, clean it with soap and water first. Don’t bother with EtOH or bleach in the incubators. It will just make you high or sick (respectively). The heat and moth balls will do the trick.

  2. The only thing that goes into a clean incubator is a clean box, with clean plates. This means each box needs to be hand washed and ideally baked 1 hr prior putting it into the incubator. In the absence of that, wash boxes and lids with soap & water, wipe down with 70% EtOH, then line the bottom of the box with mite paper. Only clean plates go into the box. This means visual inspection of the plate. Then hand picking individual worms to the plate. Then wrap those plates in parafilm. Put the whole box in a sealed ziplock style plastic bag (which hasn’t touched the floor or been in an area where you think there might be mites). Optional, check your genotypes: I’ve heard that mites can carry worm eggs on their little spines from one plate to another, but don’t know whether this is true.

  3. Repeat steps 1 & 2 for each incubator. Leave an open plate (with bacteria) on each shelf and visually inspect each plate every day over the course of ~1 week. If you see mites or signs of mite tracks, you didn’t get them all and need to try again.

  4. Clean all surfaces. This means soap and water followed by a 10% bleach treatment, lastly (optional) followed with a wipe down with sterile water (to remove the bleach smell). You should clean all personal bench-tops, common areas, microscopes, and shelves. Common areas where plates are poured should be cleaned with extra attention to detail. Stacks of papers and clutter on desks or benches where worm work is done need to be cleaned up and filed away. Not put back where they were. Any old cardboard boxes on shelves or on the floor should be trashed. All boxes that hold plates should be washed and lined with mite paper. Once those boxes are holding stock plates, they should be sealed in large ziplock style bags. Floors should be washed.

  5. Adopt a strick anti-mite policy. 1. Anything that ever hits the floor should be considered contaminated. Never store boxes on floor (yes I’ve seen people do this and they were typically the worst offenders). If a student puts their backpack on the floor, it should never then go to a bench-top. (etc). 2. Never allow old worm plates to accumulate within an incubator. Forgotten boxes in the back of the incubator become mite factories once someone brings a mite into an incubator. Throw out old plates when your 100% sure you don’t need them. 3. Store boxes within ziplock plastic bags and wrap key plates in Parafilm. 4. Keep a lookout for contamination. If you start to get other signs of contamination, like fungus or weird spots growing on plates, mites could be tracking them.

Good luck. I know it sucks.

Thanks a lot for all the information you have supplied. It took me a while to thank you but we were busy getting rid of mites!
We cleaned everything in the lab with ethanol and lindane solution. We also put the the incubators to 60 degrees to get rid of the ones in the incubators if there were any. Looks like we don’t see the mites now. Hopefully it will stay that way!!!
Thanks again for all your replies. That was great help!

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Hi all! Has anyone ever got a worm incubator profesionally fumigated? If so, any recommendation? We have repeated mite contamination in this very same incubator! The rest seem to be mite-free!