St. Louis Encephalitis (SLE). St. Louis Encephalitis (SLE) is transmitted from birds to man and other mammals by infected mosquitoes (mainly some Culex species). SLE is found throughout the United States, but most often along the Gulf of Mexico, especially Florida.Major SLE epidemics occurred in Florida in 1959, 1961, 1962, 1977, and 1990.t. Louis Encephalitis (SLE). St. Louis Encephalitis (SLE) is transmitted from birds to man and other mammals by infected mosquitoes (mainly some Culex species). SLE is found throughout the United States, but most often along the Gulf of Mexico, especially Florida.
Seven Years. Keep any tax return and documentation that includes a claim for deducting worthless securities for seven years. There you have it. Check back in a few days and I'll share a few more tips on what to keep indefinitely and how to keep your records organized and safe.
Records for tax deductions taken. Length of time to keep, and why: Seven years. 1  The IRS has three years from your filing date to audit your return if it suspects good-faith errors.ength of time to keep, and why: From six years to permanently. 1  Keep all records documenting the purchase price and the cost of all permanent improvements -- such as remodeling, additions and installations.