Hi Jim and welcome to our little MS community,
As already mentioned, there hasn't been a definitive association established with anything, lots of theories but so far none of the theories have been proven. Mono is a very common condition throughout the general population, stats are around 90% but there are no where near that many MSers. Twin studies have failed to find definitive genetic, viral or environmental associations. I believe the only thing that is agreed upon, is that 'something' is a catalyst that sets off the abnormal autoimmune response but what that is nothing is clear.......
http://www.mstrust.org.uk/information/publications/msexplained/possible_causes.jsp
I think it's probably a weak link, if your trying to work out if having viral meningitis 35 years ago, could of caused what your currently dealing with. At this stage you don't know if you do have MS or not because you said your going through some testing to find out what is wrong. The diagnostic process can take a long time to work out, there are a lot of medical conditions that also cause similar symptoms to MS, not all are neurological conditions and it may be better to not focus on any particular condition at this point in time.....
Cheers...........JJ
There actually isn't a specific treatment for viral meningitis. As per the Centers for Disease Control and Prevention:
"In most cases, there is no specific treatment for viral meningitis. Most people who get viral meningitis completely recover on their own within 7 to 10 days. However, people with meningitis caused by certain viruses such as herpesvirus and influenza, may benefit from treatment with an antiviral medication."
http://www.cdc.gov/meningitis/viral.html
They haven't found any definite links between viral infections and MS. They've seen several correlations between common viruses and MS, but nothing has pointed directly at one disease more than the other.
At any rate, leaving the meningitis untreated for 4 days would cause some neurogical problems, but it wouldn't cause MS.