Sorry just read this and a someone who's very aware of ketones I would say that if you can't check them yourselves you need to get them tested before it goes to far. I have a meter and strips (as I'm on a pump) to test and when mine were 1.5 and rising and high BSs I went to A&E. They did a test and, although levels of acid in the blood were not high, they kept me in as my ketones had climbed to 3.5. To put this in to context, I had just been put on a pump and my DSN was on long term sick so I had no one to ask about how much to adjust. To give you an idea though, the next time it happened an I was unwell, I had to put my pump on 200% additional basal rate and I had to increase my bolus just to keep my BSs below 10. I tried to drink plenty of water and ketones did then come down from 1.6 to 0.6 in about 4-6 hours.
When I had the norovirus before Christmas and was constantly vomiting my BS were fine at 6-8 but I had ketones of 1.6 - my DSN told me that as I was being sick if I could not get ketones under control from the morning to early afternoon they would have to get me into hospital. Luckily they came down.
Hope this gives you and idea but as I say in my first para got and have them checked if you're still ill and they can be dangerous.