In December 1952 and January 1953, Việt Minh representatives attended a series of lectures and an exhibition in China where they learned the specifics of biological weapons use in North Korea and northeast China. A simplified version of this information is presented in a Việt Minh pamphlet but the reports collected at this time were extremely detailed and the transcripts and summaries run to over 200 pages.

Chinese scientists and medical doctors emphasized the need for careful research and laid out three reasons they suspected the United States and United Nations militaries of using germ warfare:

1. Diseases that broke out were new to area and time of year;
2. Unusual insects and materials served as vectors;
3. Outbreaks happened after US airplanes flew by.

These scientists also pointed to the context of the US biological weapons program. They could draw on information available to the US public as shown in the following propaganda film about the US military's chemical, biological, and radiological weapons programs.

A term used at the Chinese conference to describe biological weapons, “bacteriology upside down,” came from Theodor Rosebury, one of the founders of the US's World War II biological weapons program. In 1949, Rosebury published Peace or Pestilence? Biological Warfare and How to Avoid It that warned against the use of these weapons and used the phrase “bacteriology upside down” as the title of chapter four.

Finally, reports from this conference argue that patriotic hygiene mass movement was a good way to counter effects of biological warfare. All of these themes were picked up by the Việt Minh in their own investigations. This report is held in the National Archives of Vietnam Center 3 (NAV3 BYT 5402).

Did the United States use biological weapons during the Korean War?

While the existence of both an offensive and defensive biological weapons program at Fort Detrick, MD was no secret, the use of biological warfare during the Korean War has been denied by US leaders. From Soviet Union documents made available in the 1990s, it appears that Chinese and Soviet scientists helped fabricate evidence of US biological weapons use. These documents show that some Chinese and Soviet officials knew that North Korean charges of biological warfare were false propaganda. The first notes from Soviet officials stating that the specific evidence for germ warfare in North Korea and northeast China was weak and had possibly been fabricated came in April 1953, over a year after the alleged use of germ warfare. A Soviet cable to the Democratic People's Republic of Korea (DPRK) from 1 April 1953 states, for example, "the North Koreans, with the assistance of our advisers, created false areas of exposure. In June-July 1952," it continues, "a delegation of specialists in bacteriology from the World Peace Council arrived in North Korea. Two false areas of exposure were prepared." Documents from later that April suggest that North Koreans were fabricating charges made as early as 1951.

On 2 May 1953, soon after top Soviet leaders learned of this fabrication, they called for a halt to further investigation into the charges. In terms of biological weapons use in the First Indochina War, Việt Minh leaders had no reason to suspect before this time that the charges leveled against the Americans were false. They had gained their information about germ warfare late the previous year and had already started to investigate similar suspected used of biological weapons in northern Vietnam (For a more detailed discussion of biological weapons charges during the Korean War see Rogaski 2002).