Letters to the Editor Readers comment on TB vaccines and more By Science News Staff March 6, 2020 at 5:47 pm - More than 2 years ago Share this:Share Share via email (Opens in new window) Email Share on Facebook (Opens in new window) Facebook Share on Reddit (Opens in new window) Reddit Share on X (Opens in new window) X Print (Opens in new window) Print Cellular hideout Delivering a tuberculosis vaccine intravenously instead of under the skin improved its effectiveness, Tara Haelle reported in “Injecting a TB vaccine into the blood, not the skin, boosts its effectiveness” (SN: 2/1/20, p. 12). “My main takeaway from this article is that something as big as bacteria can get inside of a cell,” reader Mike Hamm wrote.