Urgent: Antherina suraka larvae with strange symptoms

I'm rearing several suraka larvae since L1 successfully on Nerium oleander.
But today some of the L5 started to have suddenly strange symptoms of suffering: they start to vomiting or have diarrhea and twist, then they fall on the bottom of container and continue to twist and loose green liquid from the mouth.
I don't think it is a disease but some plant with some insecticide (altough I wash plants in water for 30 minutes before offering to larvae) .
Or maybe it can be some little Acarus who remain on washed leaves?
I saw a similar sympthoms with several others Saturniidae in the past and also with plants which probably are not treated by insecticide (es. Rubus fruticosus).

http://www.ecosicilia.net/suraka.avi

pas de probleme pour mes L5 actuellement elevees sur ligustrum ovalifolium.
je pense aussi que ton probleme est plus d'origine chimique que viral.

My "poisoned" larvae recovered a little yesterday after being kept the day before "drowning" in tiepid water for 15 minutes and then let dry on a paper-towel.
Maybe it was a stupid trick but I had wanted to try anyway!
Today they are feeding!
The other larvae seemed to be not affected by the insecticide in
leaves.
Yesterday I provided Nerium oleander branches from another source and washed leaves keeping them in a solution of water + bi-carbonate and then with a solution
0,5% of bleach!
Then I rinsed well the branches and gave to the larvae,
which since yesterday are feeding without warning symptoms.