SECURITIES AND EXCHANGE COMMISSION


                             Washington, D.C. 20549


                                   FORM 8-K/A
                                (Amendment No. 1)


                                 CURRENT REPORT



     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934


Date of Report (Date of earliest event reported)             September 30, 1999


                            HEMAGEN DIAGNOSTICS, INC.
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             (Exact name of registrant as specified in its charter)

         Delaware                   1-11700                   04-2869857
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(State or other jurisdiction      (Commission                  (IRS Employer
      of incorporation)           File Number)              Identification No.)

34-40 Bear Hill Road, Waltham, Massachusetts                    02451
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   (Address of principal executive offices)                   Zip Code


Registrant's telephone number, including area code  (781) 890-3766


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         (Former name or former address, if changed since last report.)









This report is filed  solely to amend the last  paragraph  of Item 1 of the Form
8-K filed on October 7, 1999 as follows.

Item 1.  Changes in Control of Registrant.

         Together  with Common Stock and Common Stock  Purchase  Warrants  owned
prior to  September  30,  1999,  these  transactions,  treating  the  options as
exercisable,  result in the Redwood Nominees  beneficially owning  approximately
29.14% of Hemagen's  outstanding  Common  Stock on a  fully-diluted  basis.  The
sellers  of the stock  named  above may be  deemed  to have been in  control  of
Hemagen prior to the  transaction of September 30, 1999 which changed control of
Hemagen to the Redwood Nominees.


                                   SIGNATURES

         Pursuant to the  requirements  of the Securities  Exchange Act of 1934,
the  registrant  has duly  caused  this report to be signed on its behalf by the
undersigned hereunto duly authorized.

                                         HEMAGEN DIAGNOSTICS, INC..



Date:  October 13, 1999                   By:   /s/ Jerry L. Ruyan
                                             -----------------------------------
                                                    Jerry L. Ruyan
                                                    Chief Executive Officer