Vi-polysaccharide conjugate vaccines are efficacious against cases of typhoid fever; however, an absolute correlate of protection is not established. In this study, we investigated the leukocyte response to a Vi-tetanus toxoid conjugate vaccine (Vi-TT) in comparison with a plain polysaccharide vaccine (Vi-PS) in healthy adults subsequently challenged with Salmonella Typhi. Immunological responses and their association with challenge outcome was assessed by mass cytometry and Vi-ELISpot assay. Immunization induced significant expansion of plasma cells in both vaccines with modest T follicular helper cell responses detectable after Vi-TT only. The Vi-specific IgG and IgM B cell response was considerably greater in magnitude in Vi-TT recipients. Intriguingly, a significant increase in a subset of IgA+ plasma cells expressing mucosal migratory markers α4β7 and CCR10 was observed in both vaccine groups, suggesting a gut-tropic, mucosal response is induced by Vi-vaccination. The total plasma cell response was significantly associated with protection against typhoid fever in Vi-TT vaccinees but not Vi-PS. IgA+ plasma cells were not significantly associated with protection for either vaccine, although a trend is seen for Vi-PS. Conversely, the IgA- fraction of the plasma cell response was only associated with protection in Vi-TT. In summary, these data indicate that a phenotypically heterogeneous response including both gut-homing and systemic antibody secreting cells may be critical for protection induced by Vi-TT vaccination.

Background Inability to communicate is very distressing for patients in the intensive care unit (ICU). Most communication exchanges in ICU are initiated by healthcare workers (HCWs). Touch screen apps may enable patients to initiate communication and improve their interactions. Objectives This study aimed to evaluate the pertinent features of iPad-based apps designed for communication in ICU. Methods Apple “App Store” and Google “Play Store” were searched for keywords “communication” and “intensive care.” Related app suggestions were screened. Two independent assessors evaluated iPad-based apps that were deemed useful. The assessors resolved the discrepancies by re-evaluating the apps and reaching a consensus. Results Nine apps met the inclusion criteria. Of these six apps were free. There were seven apps specific to intensive care. Most apps had preloaded phrases for the patient to request to see someone (e.g., family), personal hygiene (e.g., bowel care), seek help with symptoms (e.g., pain), or a comfort item (e.g., blanket). CALD Assist, Patient Communicator, VidaTalk, and YoDoc were available in more than eight languages. VidaTalk and YoDoc allowed the user to write. Four apps were deemed not suitable for routine ICU use, while the remaining five had several attractive features. Conclusion Several high-quality apps are available to assist with patient-initiated communication exchange in ICU. This study provides a guide for readers to choose the app most suited to their needs. In the opinion of the authors, YoDoc is the most suitable app for routine use in ICU. Among free apps, CommuniCare appears to be the most user-friendly. How to cite this article Dind AJ, Starr JS, Arora S. iPad-based Apps to Facilitate Communication in Critically Ill Patients with Impaired Ability to Communicate: A Preclinical Analysis. Indian J Crit Care Med 2021;25(11):1232–1240.

How to cite this article: Dind A, Starr JS, Arora S. Author's Reply to “Communication with Patients on Mechanical Ventilation: A Review of Existing Technologies” by Nair and Anand. Indian J Crit Care Med 2022;26(6):758.