He has an aide that provides care 7 days a week. However, do to the infestation the aide will not come. The home needs to be fully treated. My family will purchase all new clothing and will refurnish the apartment once treated. However, we need a place for him to stay where he can be cared for. He suffers from dementia and schizophrenia.
Have you had your brother evaluated to see what level of care he needs? Except for the early stages, dementia patients actually need around the clock care and supervision. Does this caretaker stay with him 24/7? I think I would explore what kind of care your brother needs and use this opportunity to either place him or get the right amount of care brought into his home?
If this infestation occurred once, then what would stop it from reoccurring? Maybe, there needs to be more hands on care and control over the environment. For safety reasons, I would consider it an emergency. Are you talking about mice infestations, fleas, roaches? It's sounds very unsafe. I'd get him some help ASAP.
Some places will allow his Aide to still care for him as long as she has all her papers in order, such as a current TB test, background check, etc.
If there is no social worker, call the county health department.