Lymph Letter

In a letter in the June issue, Su Cooper mentions that her ancestor had been fined for not allowing the vaccination officer to take lymph from their children. I thought I would clarify the reference to vaccination “lymph”.

Lymph is fluid in the lymphatic vessels and is very hard to collect, but fluid from interstitial spaces in various tissues drains into the lymphatic system. Thus, tissue fluids used to be sometimes also referred to as lymph. In the writer’s case, the lymph collection relative to vaccination is most certainly vaccination against smallpox. A technique known as ‘arm-to-arm vaccination’ was used, and considered mandatory, around that time for live virus vaccination against smallpox.

When poxviruses are injected into human or animal skin, fluid-filled swellings (‘vesicles’) appear within days at the site of vaccination. The ‘lymph’, ‘vaccine lymph’ or ‘vaccinia lymph’ fluid and cells within the vesicle were collected, and this lymph material was sequentially passed on as a vaccine to others in the community. The same technique was also used to sequentially transfer the vaccination between people during long ship voyages to distant countries.

Due to the risk of transmitting other diseases using arm-toarm human vaccine lymph, this technique was banned in the UK in 1896, in favour of using vaccinated calves to generate the vesicles. ‘Calf lymph’ was then used to vaccinate humans against smallpox.

The Wellcome Collection has a number of records relating to this subject: bit.ly/well-lym. JoAnn Schuh, Washington, USA

EDITOR REPLIES: Thank you for that fascinating background JoAnn.