Over the past 2 years, vaccines against SARS-CoV-2 have been administered throughout the world at a record pace. Despite allocations being uneven between richer and poorer countries, more than 11 billion doses have been distributed globally. Vaccine doses have been carried from laboratories and factories to remote communities using almost every mode of transport imaginable, from drones, helicopters, and snowmobiles through to camels, elephants, and horses. Wind the clock back more than 200 years and the first global vaccination campaign used a far more sinister method to transport its inoculations—the bodies of enslaved and orphaned children. The connections between the distribution of the smallpox vaccine and the Atlantic slave trade are being highlighted during Vaccine Voyages, a self-led walking tour taking place as part of the Edinburgh Science Festival on April 9-24. A series of 25 panels placed along North Meadow Walk in Edinburgh, UK, guides visitors through the story of the discovery of English doctor Edward Jenner's smallpox vaccine in 1796, and its spread through the Spanish empire from 1803 to 1806 during the Royal Philanthropic Expedition authorized by King Carlos IV of Spain. The text for the panels was written by Farren Yero, a Postdoctoral Associate in the Department of Gender, Sexuality & Feminist Studies at Duke University, NC, USA, and currently a Consortium of Humanities Centers & Institutes-American Council of Learned Societies Fellow in the Institute for Advanced Studies in the Humanities at the University of Edinburgh, UK. Yero is a historian of Latin America and the Caribbean who specialises in gender studies and the history of race, health, and medicine, and her book project is entitled Atlantic Antidote: Race, Gender, and the Birth of the First Vaccine. Her panels’ text is accompanied by illustrations by Jacqueline Briggs, a half-Scottish, half-Papua New Guinean designer who trained in the Duncan of Jordanstone College of Art & Design at the University of Dundee, UK. Tucked away in a corner of The Meadows, one of Edinburgh's best-known public parks, the panels begin by drawing an immediate contrast between the often-told story of Jenner's development of his smallpox vaccine and the pre-existing technique of “variolation” in North Africa, where small amounts of a virus obtained from patients were used to induce immunity. “Healers in India, China, and the Middle East practised forms of variolation centuries before Jenner's experiments”, the panels explain. Placing Jenner's discovery in that global context—rather than focusing solely on the development of medicine in Europe—lays the groundwork for the little-known story that emerges over the panels, documenting the harrowing accounts of enslaved people being forced to carry the cowpox virus, which was used to inoculate against smallpox. After explaining the development of the smallpox vaccine, the panels recount the story of the María Pita, the ship that set sail from Spain in 1803 carrying expedition director Francisco Xavier de Balmis and fellow medical practitioner José Salvany, along with 22 orphaned boys, who were ‘carriers’ of the live cowpox virus. Each pair of boys had lymph fluid harvested from pustules on their arms used to vaccinate the next pair. After reaching Puerto Rico, the expedition sailed to Venezuela, Cuba, and Mexico, where the 22 orphaned boys were promised an education, which the panels contrasted with the fate of additional enslaved children, mostly girls, who were then used to carry the virus between the Atlantic ports. The phrase, “We do not know what happened to these enslaved people”, is repeated again and again on the panels as tales from the voyage are recounted. Away from the expedition, other Spanish governors and doctors also used enslaved girls to move the virus between islands, using lymph fluid harvested from them to inoculate their local populations. While much of the text is accessible to a lay audience, a few extra words could have added further context, such as describing Rio de Magdalena on panel 18 as Columbia's main river, explaining that Canton is the Chinese city of Guangzhou on panel 22, or expanding on the phrase Southern Cone on panel 24 to explain it means the southernmost portion of South America. Visitors could also be offered help by the festival organisers to locate the panels—the very general description of “North Meadow Walk” covers a path stretching for more than 1 kilometre in length, whereas the panels are in fact along the eastern portion, opposite Meadows City Tennis Club. Vaccines Voyages comes at a point when the city of Edinburgh is also wrestling with its colonial past. In the wake of the Black Lives Matters protests in 2020, the City of Edinburgh Council set up an independent slavery and colonialism legacy review group, chaired by Sir Geoff Palmer, a Professor Emeritus in the School of Life Sciences at Heriot-Watt University, UK, to consider statues, street names, and buildings with links to slavery. The council has already erected a plaque beneath arguably the city's most contentious statue—the Melville Monument in St Andrew Square—to Henry Dundas, a Georgian politician accused of prolonging the Atlantic slave trade. The new plaque has drawn criticism from some historians, who argue Dundas was not solely to blame for delays to the abolition of slavery. For more on Vaccine Voyages see www.sciencefestival.co.uk/event-details/vaccine-voyages For more on Farren Yero see www.farreneyero.com For more on Jacqueline Brigg see www.jacquelinebriggsillustration.com © 2022 Peter Ranscombe 2022