Absense of chairman of audit committee in agm

This question is slightly odd, so please bear with me.

As per Clause 49(II)(A)(iv) of the Listing Agreements, the Chairman of the Audit Committee of a Listed Company must be present in the Company's AGM to answer shareholders' query. However, as on the date of AGM, the Chairman becomes very sick, thus rendering him completely incapable to participate in the AGM.

What could be done in such a case?