See ESC right:

Health care services, access to

Relevant ICESCR Articles:

12(1): The States Parties to the present Covenant recognize the right of everyone to the enjoyment of the highest attainable standard of physical and mental health.

12(2)(d): The steps to be taken by the States Parties to the present Covenant to achieve the full realization of this right shall include those necessary for:
(d) The creation of conditions which would assure to all medical service and medical attention in the event of sickness.