World War I disrupted communications so seriously that the IAMM as a viable international organization ended abruptly. No further international meetings were held until 1960 and no international presidents were elected again until 1969. Prof. Ludwig Aschoff was to have served as International President until the next triennial meeting in Munich but that meeting was never held.
The U.S. and Canadian members continued the organization as the American Section (later called the American-Canadian Section). It was kept alive through the efforts and energy of Maude Abbott.
The seventh annual meeting and the first meeting of the American Section was held on April 9, 1914 in Toronto in conjunction with the meeting of the American Association of Pathologists and Bacteriologists. Prof. R. M. Pearce presided as President of the American Section. The program consisted of papers and demonstrations of macroscopic and microscopic techniques for the most part. Correspondence indicates that attempts to organize sections in various countries was continuing at this time without much success. Sections in England, Germany, Switzerland, and France functioned briefly but they too succumbed to the interruption of World War I.
The stationery used by Maude Abbott in 1914 continued to list Prof. Aschoff as President on the letterhead although her letters indicated that Prof. Pearce was President of the American Section of the IAMM. On December 22, 1914, a letter from Prof. Pearce (Philadelphia) indicated that the war had interrupted correspondence between Canada and the warring countries and that he had, as '"a citizen of a neutral state," appointed Prof. A. J. Smith (Philadelphia) as an acting Secretary-Treasurer for the U.S. Division. When the war ended, Maude Abbott resumed her full duties as Secretary-Treasurer.
The eighth annual meeting was held at the Washington University School of Medicine on April 1, 1915 on the day preceding the AAPB meeting. The program consisted of six papers on technique and nine demonstrations.
An Editorial in Bulletin No. 5, published June 1915 states:
"This Bulletin contains the proceedings of the last International Meeting of the Association which was held in London in August 1913 in conjunction with the XVIIth International Congress of Medicine as well as those of two meetings of the American Section held in the country (U.S.A.). Since to recall these proceedings is to remember London as it was during the concourse of nations of that great congress, and to bring sharply before the mind the changed conditions today, when the very men who met each other so cordially in the friendly interchange of scientific thought, are now engaged in an encounter of deadly hostility. So serious has the situation become and so terrible the loss of life, that all other matters sink into insignificance in comparison with the overpowering need for the amelioration of the belligerents. Nevertheless, the duty remains for such an Association as this, to preserve its integrity, and to cherish the memory of the international amity in which it originated, in the hope that in an happier day, when a just peace may at last be proclaimed, it may act as one of the links that must bridge across the chasm that divides those who are now bitter foes. It is with this thought and in the hope that we introduce the Bulletin to our membership - - to whom it has been long pledged."
A subsequent editorial by Prof. Warthin and Maude Abbott in Bulletin No. 6, August 1, 1916 indicated that all international societies had ceased to function during the war but that the local American Section of the IAMM had continued to function.
The Bulletin was being supported by the Strathcona Fund and not from dues which largely ceased to be paid.
New members elected at this meeting included Prof. F. B. Mallory, Prof. C. H. Bunting, Dr. Carl V. Weller, Dr. R. J. Terry, Dr. R. C. Rosenberger, Dr. Horst Oertel, Prof. John Sundwall, and Dr. Plinn Morse.
The ninth meeting was held at the Army Medical School, Washington, D.C. On May 8, 1916. Prof. A. S. Warthin (Ann Arbor) chaired this meeting. At this meeting, a need was expressed for square glass museum jars. The supply obtained from Germany had been discontinued by the war. At this meeting, Prof. Oskar Klotz (Pittsburgh) was elected President for 1916-1917 and served until 1920. A financial statement at this meeting revealed a fund balance of $202.30. The income from members fees was $189.52 and from interest on the Strathcona Fund $300.00 and other interest $7.07. Expenses included $411.10 for publication of the Bulletin.
The tenth meeting was held at the Academy of Medicine in New York on April 5, 1917. Prof. Klotz was re-elected President for 1917-1918. Prof. Klotz reported that the Phoenix Glass Company of Pittsburgh had agreed to manufacture square glass jars for museum purposes. The price for 5 x 5 x 3 cm. jars was $1.60 per dozen; for 15 x 25 x 10 cm. jars the price was $27.75 per dozen. There were many sizes in between the above. An American substitute for Russian paraffin was reported as being made.
On April 5, 1917, the following telegram was dispatched: "The American Section of the International Association of Medical Museums places itself in the present emergency and offers the services of its workers and resources in its special field of research in any the National Committee may suggest. Signed, Oskar Klotz, President."
World War I began in Europe in August 1914. The U. S. officially declared war on the 6th of April 1917, the day after the above telegram was sent during the tenth annual meeting.
At the tenth meeting a discussion took place on the clashing of the time of the meetings of four societies with kindred interests, namely, the American Association of Pathologists and Bacteriologists, the American Section of the IAMM, the Cancer Society, and the American Association of Immunologists. Some sort of federation was suggested. Scientific publications in the Bulletin evolved during the war years from predominance of papers on the preservation of gross specimens to histopathological studies concerned with the causes and manifestations of specific diseases such as trinitrotoluene (TNT) poisoning in munitions workers.
Bulletin No. 6 contained two full page plates in color from camera lucida drawings showing special stains of sympathetic ganglion cells and blood cells of a human and a goat, indicating an increasing interest in histopathology.
Maude Abbott published a Special War Bulletin in May 1918 but distribution was restricted to allied and neutral countries. In this issue there were articles on trench foot, gassing, industrial poisonings, "Soldier's heart," war oedema, insect vectors, venereal disease, tetanus, gas gangrene, embolism and shock, and many other war related diseases.
An annual meeting scheduled for March 28, 1918 was canceled, however, members were invited to send exhibits to the American Association of Pathologists and Bacteriologists meeting in Philadelphia, March 29-30, 1918.
The twelfth annual meeting was held in the Guild Hall in the Church of the Ascension, 30 Kentucky Avenue, Atlantic City, New Jersey on June 16, 1919.