Thank you for your help in advance. There is a well-documented literature concerning infantile beriberi in southeast Asia and the Philippines. The development of beri beri in the infant was seldom noticed until a sudden acute and often fartal episode developed. The thiamin levels in the milk secreted by the thiamin-depleted mothers was simply inadequate to prevent beriberi in the suckling infant. The signs and symptoms of infantile beri-beri appear and progress so fast that by the time the mother sees something is wrong with the infant there is very little time left to arrive at the hospital.
Infants often expire on the way to the hospital.
Since thiamine is not really stored in the body infants will depends very much on the daily intake of B1 which in poor rural areas will be fluctuating highly. We never saw infantile beri-beri after giving daily supplements to lactating women. This seems to me the best immediate solution. In southeast Asia, traditional communities have sometimes post-natal practices where the mother is put on a bamboo bed above hot charcoal. Thsi can be even for a few days.