In spring, summer and autumn 2020, one abiding argument against controlled human infection studies of SARS-CoV-2 vaccines has been their impact on local communities. Leading scientists and bioethicists expressed concern about undue usage of local residents’ direly needed scarce resources at a time of great need and even about their unintended infection. They recommended either avoiding CHI trials or engaging local communities before conducting any CHIs. Similar recommendations were not made for the alternative—standard phase III field trials of these same (...) vaccines. We argue that the health effects of CHI studies on local residents not participating in the study tend to be smaller and more positive than those of field trials. That is all the more so now that tested vaccines are being rolled out. Whether or not local community engagement is necessary for urgent vaccine studies in the pandemic, the case for its engagement is stronger prior to field trials than prior to CHI studies. (shrink)