There are international standards for the provision of health care for people who are detained.

The Mandela Rules state: "The provision of health care for prisoners is a State responsibility. Prisoners should enjoy the same standards of health care that are available in the community, and should have access to necessary health-care services free of charge without discrimination on the grounds of their legal status."

https://www.unodc.org/documents/justice-and-prison-reform/GA-RESOLUTION/E_ebook.pdf

The junta may not recognise them.

https://www.irrawaddy.com/news/burma/no-word-month-families-detained-senior-nld-figures-worry-health.html

Jamie