These files reveal more about the secret work being carried out in British sites at Porton Down and elsewhere. This work was carried on in spite of the fact that such warfare had been outlawed under international law. Apparently neither side used bacteriological weapons fortunately. This is from the Guardian(UK) There is much more detail in the actual article.
Files reveal Britain's secret biological weapons trials in second world war
Porton Down scientists studied foot-and-mouth, typhoid and cholera for disease attacks
Owen Bowcott and Rob Evans
British scientists experimented with ways of spreading foot-and-mouth disease, and lethal infections such as dysentery, cholera and typhoid in secret biological warfare trials during the second world war.
An extensive list of the contagious agents and plagues that could be turned into weapons of mass destruction is revealed in files from a War Cabinet committee released to the National Archives.
The government was known to have produced 5m anthrax-filled cakes to infect cattle in Germany during the war, but the latest documents show research was carried out into a far larger variety of diseases, mostly in Porton Down, near Salisbury, and Pirbright in Surrey.
Experts reported to the War Cabinet's Porton experiments sub-committee, which acknowledged that "bacteriological warfare" was outlawed by the 1925 Geneva protocol. The minutes, only now released, are labelled "secret" and "to be kept under lock and key". One session on "Toxin X" - thought to be botulinum - was so sensitive the minute records: "Not circulated."
An interim report in January 1941 said: "The diseases considered most likely to be effective in bacteriological warfare are:
• Human diseases: enteric group (typhoid and para-typhoid), dysentery and cholera.
• Animal diseases: anthrax, foot-and-mouth disease, rinderpest, glanders, and swine fever. (Anthrax and glanders also affect human beings under conditions favourable for infection)."