I'm from India and currently its retreating monsoon season and it's a bit cold , the smell is like poop mixed with turmeric but really bad.I keep trying to roll him in a cloth and keep him warm but he keeps rolling out .The entire day he was on his side sleeping, he tried to get up a couple times but keeps falling over.He barely has the energy to lift his head up.Thanks for checking the mouth. We can rule out canker as the source of illness and odor.
Termites or flying ants won't make a chick sick. But this chick had to have come into contact with something toxic for it to become this sick so quickly.
It certainly would help if you'd include your location in your profile. It might give us a clue.
For example, several weeks ago, I had two chicks become very sick very fast and die, and I discovered a poisonous caterpillar was the villain. It happens to inhabit ponderosa pine trees, and I found two of them just feet from my run.
Can you try to describe more clearly what the odor coming from this chick smells like?
For example, is it sour like buttermilk or sour milk? Is it like roadkill? Is it stinky like poop?