Whether insured or not, it is important for property owners to document damage with photographs or video, and immediately, to begin loss mitigation procedures themselves; or hire a qualified contractor to do this on their behalf. It is totally inappropriate to put off mitigation while waiting for an insurance claims representative to arrive on the scene to evaluate the loss.
By that time, in all probability sufficient time will have passed to grow and amplify microorganisms, which may not be covered by insurance. Loss mitigation is defined by insurance policies as "reasonable and prudent measures designed to preserve, protect and secure property from further damage," including microbial growth and amplification.