When I was younger myself, my brother and my sister were minded after school by a family who lived locally. We were cared for mainly by Breda. Peter, her husband, was a fire fighter. I remember one day there was an unusual fuss in the house. Peter, while out on a job with the fire crew, had contracted TB while resuscitating someone. I’m not sure if it was a time before there were protective coverings for mouth to mouth resuscitation, or if the situation was more complicated and there went a readily available option. Either way, he had contracted tuberculosis. Because of this, everyone in his household had to be tested. This included my sister, my brother and I because we were there so much. It was unusual at the time because most people —including my mum —had though TB had been eradicated from the Island already. While it wasn’t completely gone, Tuberculosis used to be more common in Ireland. There were nearly 7000 cases a year in the early 1950s. The incidence of TB has declined steadily since then down to 267 TB cases in 2019. Its almost impossible to completely get rid of a disease. As long as there travel between nations —via tourism, economic migration or people seeking asylum —there is the possibility of virus moving across borders. In 2019, 40% of people who got TB were born in Ireland, 44% were foreign born and 16% did not have country of birth reported. None of us had contracted it.

Eula Biss in On Immunity charts a facinating history of immunisation and vaccination. She point to its roots in folk medicine and farming. Milkmaids in 1700’s England had faces unblemished by smallpox. At the time Smallpox was rampant in the country and many bore the scars of the disease on their faces if they survived. She goes on how:

“Folk knowledge held that if a milk maid milked a cow blistered with cowpox and developed some blisters on her hands, she would not contract smallpox even while nursing victims of an epidemic. […]During a smallpox epidemic in 1774, a farmer who had himself already been infected with cowpox used a darning needle to drive pus from a cow into the arms of wife and two small boys. The farmer's neighbours were horrified. His wife's arm became red and swollen and she fell ill before recovering fully, but the boys had mild reactions. They were exposed to smallpox many times over the course of their long lives, occasionally for the purpose of demonstrating their immunity, without ever contracting the disease. Twenty years later, the country doctor Edward Jenner extracted from blister on the hand of a milkmaid’s hand and scraped it into the arm of an eight-year-old boy. The boy got a fever but did not become ill. Jenner then exposed the boy to smallpox, which did not infect him. Emboldened, Jenner continued his experiment on dozens of other people, including his own infant son.

Early on in the lockdown, there was a study indicating that the BCG vaccine for tuberculosis could help to protect against Covid-19. It was called “a potential game-changer” in relation to the global efforts to curb the pandemic. The research, carried out in Trinity College Dublin, indicated that countries whose populations have high levels of BCG vaccination had significantly fewer Covid-19 deaths. Bacille Calmette-Guerin is given to babies to prevent childhood tuberculous, meningitis and miliary disease; it is part of the early rounds of vaccination. Current studies are ongoing in relation to its benefits with regard to COVID 19, but it is known that the BCG vaccine confers a broad protection against other infectious diseases as well as those it is specifically protects against. However, Ireland has had no BCG vaccine since May 2015 and so children currently aged five and under in Ireland will not have the vaccine.