We recently received a response from the NIH regarding our concerns about the NIH tick feeding study and the risk of tickborne infections from the larval ticks that researchers intend to place on patients to feed. We have written the NIH about this several times. Our latest letter focused on the newly identified pathogen, Borrelia miyamotoi, which can be transmitted to larval ticks through the mother's eggs. We asked the NIH to tell us what bacteria they test for in the larval ticks to ensure that patients in the study are not at risk. According to the NIH, the following pathogens are screened for: Borrelia burgdorferi, Babesia microti, Anaplasma phagocytophilum, Borrelia miyamotoi, Bartonella spp, Rickettsia sp., deer tick viruses and orbiviruses. We are glad to see that these pathogens are being screened for but remain concerned that unidentified pathogens nevertheless place patients at risk in the study.