Privacy of medical records
Q: How long does it take if I was declined for health insurance, for my medical records to be available to view by other health insurance companies?
A: Your personal medical records are never available to anyone unless you specifically give permission for their distribution. Insurance companies do not have any superior method of access.
Your question might refer to the Medical Information Bureau (MIB) which is a database about insurance underwriting rather than medical records. In this case the time of distribution issue is likely a moot point since any company that cares about prior declines asks the applicant directly whether there has been a previous "decline". The main source of information on eligibility is the applicant's own statements is you and the application is integrated with the insurance contract.
Since MIB records maintained in electronic format and accessed through the Internet by participating insurance companies, the update occurs at the actual time of an underwriting decision. As far as we know there is no delay in communicating underwriting decisions.
Some insurance companies do not ask about prior declines and this is a safer route for anyone who has been previously declined for insurance. See the insurance availability chart at "Health Insurance for Special Situations".
None of the online enrollment insurance companies listed here at MedSave.com will decline an application. Some applications may not be submitted due to eligibility but this is legally different from a "decline".