Usage Information
Abstract
As the COVID-19 pandemic continues, long-term immunity against SARS-CoV-2 will be important globally. Official weekly cases have not dropped below 2 million since September of 2020, and continued emergence of novel variants has created a moving target for our immune systems and public health alike. The temporal aspects of COVID-19 immunity, particularly from repeated vaccination and infection, are less well understood than short-term vaccine efficacy. In this study, we explored the effect of combined vaccination and infection, also known as hybrid immunity, and the timing thereof on the quality and quantity of antibodies elicited in a cohort of 96 health care workers. We found robust neutralizing antibody responses among those with hybrid immunity; these hybrid immune responses neutralized all variants, including BA.2. Neutralizing titers were significantly improved for those with longer vaccine-infection intervals of up to 400 days compared with those with shorter intervals. These results indicate that anti–SARS-CoV-2 antibody responses undergo continual maturation following primary exposure by either vaccination or infection for at least 400 days after last antigen exposure. We show that neutralizing antibody responses improved upon secondary boosting, with greater potency seen after extended intervals. Our findings may also extend to booster vaccine doses, a critical consideration in future vaccine campaign strategies.
Authors
Timothy A. Bates, Hans C. Leier, Savannah K. McBride, Devin Schoen, Zoe L. Lyski, David X. Lee, William B. Messer, Marcel E. Curlin, Fikadu G. Tafesse
Usage data is cumulative from February 2025 through February 2026.
| Usage | JCI | PMC |
|---|---|---|
| Text version | 2,453 | 436 |
| 169 | 30 | |
| Figure | 252 | 0 |
| Table | 88 | 0 |
| Supplemental data | 66 | 4 |
| Citation downloads | 120 | 0 |
| Totals | 3,148 | 470 |
| Total Views | 3,618 | |
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.
