N.Y. Pub. Health Law § 367

§ 367. Certain cities; deputy commissioners; powers. In case of the\nabsence or disability of the commissioner of health or health officer in\ncities having a population of less than one hundred seventy-five\nthousand, or of any vacancy in the office, the deputy commissioner of\nhealth, when there is one, shall discharge the duties of the office\nuntil the commissioner of health or health officer returns, his\ndisability ceases or the vacancy is filled.\n