43.—Where—

(a) circumstances have arisen in which a provision of this Part of this Act or of any regulations made thereunder requires a person to take a precaution against the infection of other persons with a particular infectious disease, and

(b) such person has failed to take the precaution, and

(c) any other person has been without his knowledge exposed by such failure to the risk of infection with the disease, and after such exposure has been infected with the disease,

in any action against the first-mentioned person by such other person for damages suffered by reason of his having been infected with the disease, the Court shall presume that such infection was the direct result of the failure to take the precaution unless the Court is satisfied (and the onus of so satisfying the Court shall lie on the defendant) that by reason of the time of such infection or for any other reason it was unlikely that such failure caused such infection.