Notwithstanding the provisions of any general, special or local law or administrative code to the contrary, but except for the purposes of the workers' compensation law and the labor law, any condition of impairment of health caused by leptospirosis, resulting in total or partial disability or death to a paid member of the uniformed force of a paid sanitation department, where such paid member is drawn from competitive civil service lists, who successfully passed a physical examination on entry into the service of such department, which examination failed to reveal any evidence of such condition, shall be presumptive evidence that it was incurred in the performance and discharge of duty, unless the contrary be proved by competent evidence.