Mite Infection in C.elegans worm plates

Hi Guys,
I have been working on C.elegans for several years but I never had a severe mite infection like this time.
I have over 100 NGM plates with C.elegans and almost all have mites in the range of 10-20 for each plate.

My problem is that I need these worms and I do NOT have back up.

I would like to ask some questions before I do something. This is very serious to me.

  1. I want to save my worms. What would be the best way ? I can open the plates and pick worms to move to new plates ? Do I need to put the plates in 15 degrees to slow down mites first?
  2. Is it likely that I can pick mite contamination as well when I pick worms ? Maybe the chance of getting mites are lower after 2-3 times of transfer.
  3. These mites can jump and I hope I am not get sick. I don’t mite of getting mite bites as long as it is not severe.

Best regards,

I’m not familiar with mites that can jump, so my experience may be of limited use. Still, here’s my advice, from what I’ve seen, even though your mites may be different:

  1. Mites are a pain, they can eat worms, can carry worms between plates, and always carry nasty bacteria and fungus. But they don’t tend to move or reproduce amazingly quickly, compared to elegans; it’s not that hard to eliminate an infestation, if you can provide clean plates and a clean place to put them. It’s even possible to eliminate a mite infestation by picking off mites and mite eggs from worm plates, instead of picking worms over, though I’ve never done that with elegans (it’s easier with Heterorhabditis) and don’t really recommend it.
  2. Setting up clean working and plate storage areas is important. Ethanol will help a bit, by making things clean and getting rid of food sources, but it won’t kill mites or mite eggs. Flame will, but (obviously) be careful. Or just a lot of hot soapy water, which also won’t kill mites but may wash them away. Watch out for cracks that may host mite populations, and try to seal them up, even with cheap silicone sealant. If you’re using incubators, and can empty them for a day or two before carefully refilling them only with mite-free plates, empty them and set them to 60 C for a day or two, and clean their interior as best as you can. This should at least knock the mite population down a lot. If you have spotted plates at room temperature for more than a couple of days, keep an eye out for mites moving into the plates, especially at the edges and on the bottom of the stack. If you’re fighting mites, clean these areas thoroughly and frequently.
  3. Mites don’t seem to like traversing thin films of mineral oil, and don’t seem to like walking across metal; also, unlike parafilm, they can’t burrow through metal. The mineral oil can be a pain (it gets everyplace) but wrapping plates or plate boxes in aluminum foil seems to help.
  4. You should absolutely be picking your worms away from the mites, as soon and as often as possible. This will obviously get better if combined with the mite control methods above.

To HillelSchwartz
Yes, I’ve never seen this types of jumping mites in my life until now. I am working in China and these jumping mites jump too fast and literally disappeared from the site since they are too small and too fast, unlike those slow ones I have seen in US. Thank you very much. I guess your answer with various methods will help me out. As soon as my plates are ready I will move them ASAP.

A tip I got from Shawn Ahmed; put your worm boxes on fly paper (also known as anti-mite paper):
https://www.carolina.com/drosophila-fruit-fly-genetics/anti-mite-paper-18-in-x-10-ft-roll/173115.pr

Also, never, ever, ever keep old chipped plates around. The mite life cycle is much longer than that of the worms, so if you practice good worm hygiene, your mite problem will stay minimal. But they say that a lab never gets rid of mites.