You can say all day and night that some people who were not "properly diagnosed" don't know they have parasites, but when you have worms coming out of your skin and every orifice in your body, you know you have them.
Doctors are useless. I finally found a doctor who gave me an ELISA test and diagnosed me, after over a year of knowing exactly what I had. I still can't get what I need from him, though, because he sees no use in the using Doxycycline for parasites, so I have to pay 5 times the price at an online pharmacy.
I will never be "cured," because strongyloides can't be cured once they have disseminated. Sad, but true.