Maybe that's why she's lagging behind the others in migration.
However, Monarchs that make it to the ELF stage c OE maybe an evolutionary step to living c the disease, much like a healthy human lives c many viruses and bacteria which in our history have once been disease organisms. Think influenza.
These surviving imagos (adults) will pass on their genes to their eggs along c the spore. Hopefully, some of these, or at least one, may make it to eclosure s disease.
Unfortunately, with the Monarch's low numbers, OE and other maladies are the last thing they need.

Just a note,
Would it be feasible or possible to challenge captive raised Monarch cats with killed OE? It could be raised in a lab and killed c radiation or heat and sprayed on their host as sort of an oral "vaccination".
This would be impossible to do at home, but there are people c those resources and capabilities that could come to the Monarchs' aid. It could be sold as a powder and mixed c water, like Milky Spore. Someone could make a mint.

Well, I've been on the phone with St Gabriel Organics discussing possible solutions to the OE problem. So far, the only thing we can do for now is practice sterile technique and euthanize any insect infested c this protozoan.
We both agreed it would be difficult to grow this parasite outside the host and a killed "vaccine" would be improbable.
Down the road, we may have the option of a crude synthetic "vaccine" or even striving to breed a disease resistant strain of Monarch.

Leafhead, I like your thinking re: "vaccines" and acquired or aided immunity to OE. My mind is on OE as I work with these eggs, instars, examine then sterilize milkweed, etc. I was changing a 4-5th instar's water and food, when to my horror it fell into some dilute bleach-water ! I thought it would have died instantly. I fished it out and rinsed it off well, then gave it the choicest, tenderest MW I had reserved for babies. It went wild with this fresh and young MW and ate like a pig for hours! I had an idea similar to yours, what if a hint of bleach had gotten into it's system and killed or partially killed the OE?

Having been married to a chemist, I often wish I could access his knowledge and love of "challenges" and apply it to OE. After seeing the diseased Monarch in my yard, the last group of eggs I washed in a mild bleach-water solution, and marked their container as such. Former eggs I allowed to hatch on the stem as found, washed with water only. Will see how they eclose.

I appreciate that you looked into OE and called about it. I am frustrated at the inconsistent information I'm finding online about bleach working, not working, etc....how much to use, how long...etc. About changing their MW type, etc. Also if these winter bred Monarchs will be confused, fit in? Will aiding unnatural behavior be of any benefit in the big picture?

Hopefully a "vaccine" or a genetic tolerance for OE will evolve. The poor Monarch--global warming, rapid destruction of it's winter forest in Mexico and native habitats, GE crops, OE..This is an inspiring species...Seems adaptation is their strong suit, yet their radical decline is sobering.

Sobering is certainly one word that fits. I'm still trying to be optimistic that we can have an impact. Every time I'm out driving, I see potential areas ripe for restoration and introduction of native plant species. If we could just find someone who had the time and interest to investigate such places and get permission for us to plant in these areas. I have enough seed collected to make a decent start.

Martha

Martha, an optimistic outlook is always best. I like your optimism. I think many want to make an impact on this amazing species which is still a mystery to scientists in many ways. It seems like the Monarch is up against so much-the poster 'child' for survival in a world where all that once was is rapidly becoming something else.

If you see a field that is unused could you toss some seeds out the window as you drive by? Or you could find out the owner through county records and contact the owner for permission. A good article on the Monarch crisis could be shown the person you are asking. Maybe property owners with unused land could be contacted via emails and asked.

On windy days, I sometimes throw seeds up into the air for them to find good homes. One poster said he releases seeds out the window as he drives... :)

Leafhead, I was thinking about what you wrote on genetic adaptation to OE. If crops can be genetically engineered to resist an herbicide, and certain rootstocks can be used to graft roses and other plants to be immune to nematodes, why can't milkweed be genetically engineered with something that would be tolerated by the caterpillars, but not tolerated by the OE parasite? When the caterpillar's digestive enzymes release the OE in the spore, it's then destroyed by the (blank) also present in the caterpillar from the new variety of MW...?

That's true genius!! I was thinking of breeding the butterflies as well, but I like your idea better.