Children's Bodies and the Transfer from Kyoto to Fukui
As a back-up for the glass containers, Kasahara Hakuō recruited two pairs of parents with young children for arm-to-arm transfers, one from Kyoto and one from Fukui.
On 11/16, Hakuō initiated the transfer from Kyoto to Fukui by vaccinating the two children from Kyoto. After confirming that pustules had developed on their arms, he traveled with the children and their parents to an inn in Nagahama on Lake Biwa, an important way station en route to Fukui. On 11/22 the children's pustules had ripened, and Hakuō extracted lymph from their arms and transferred it to the two children from Fukui, who had traveled to Kyoto for this purpose together with their parents. The family from Kyoto then returned home, and Hakuō and the second family hiked back to Fukui, crossing Tochigi Pass in the middle of a heavy snowstorm [Senkyōroku]. On 11/24, the party reached the highway station of Imajō, where a physician from Fuchū was already waiting with three local children in tow. Hakuō vaccinated one of these children as a back-up. On 11/25, the travelers arrived in the castle town of Fukui, where Hakuō immediately began to vaccinate further children. He probably used the lymph from the glass container at that time, as the pustules of the arriving children would not yet have been ready for extraction [Fukui-ken igakushi, p. 177].
Although arm-to-arm transfer turned out to be unnecessary in this case, it later became the preferred method of transmission due to its reliability. The author of "Gyūtō Kaihei" ("Uncovering Cowpox") from 1852 argued that scabs should only be used in rare cases, for example for long-distance transfers, because they were more likely to result in "spurious" pocks and did not offer the same degree of protection as direct transmissions [Umihara 2014, p. 196].
Click here to go back and explore more "Vaccine Stories."