Table 3.
Clinical progression among individuals infected with SARS-CoV-2 according to infecting lineage
| Episode type | Outcome | Events, n (Rate per 10,000 days) | Hazard ratio (95% CI), JN.1 vs. non-JN.1 infection | ||
|---|---|---|---|---|---|
| S-gene detected (non-BA.2.86 lineage) | S-gene target failure (BA.2.86-derived lineage) | Unadjusteda | Adjustedb | ||
| N = 4614 | N = 3080 | ||||
| Episodes associated with all causes | |||||
| Emergency department presentation | 126 (24.6) | 33 (11.4) | 0.41 (0.27, 0.60) | 0.47 (0.31, 0.70) | |
| Hospital admission | 36 (4.0) | 7 (1.6) | 0.33 (0.15, 0.76) | 0.50 (0.22, 1.13) | |
| ICU admission, mechanical ventilation, or death | 9 (0.8) | 2 (0.4) | 0.40 (0.08, 1.89) | – – | |
| Death | 5 (0.5) | 1 (0.2) | 0.38 (0.04, 3.33) | – – | |
| ARI-associated episodesc | |||||
| Emergency department presentation | 22 (4.2) | 5 (1.7) | 0.35 (0.13, 0.96) | 0.40 (0.14, 1.13) | |
| Hospital admission | 18 (2.0) | 1 (0.2) | 0.09 (0.01, 0.68) | 0.13 (0.02, 1.04) | |
Data encompass the primary analytic cohort (N = 7694 individuals), comprised of individuals testing positive for SARS-CoV-2 from tests undertaken in outpatient settings between 1 December, 2023 and 30 January, 2024 which were processed via TaqPath COVID−19 Combo Kit assays, who belonged to KPSC health plans for at least 1 year prior to their index test date. We verified that the proportional hazards assumption was met by visual examination of parallel trends in Kaplan–Meier curves (Fig. S1) and by testing for non-zero slopes of Schoenfeld residuals from fitted models; for each fitted model, this test yielded two-sided p > 0.1.
aUnadjusted hazard ratios are computed via Cox proportional hazards regression models matching on week of testing alone.
bAdjusted hazard ratios are computed via Cox proportional hazards regression models matching on the week of testing and controlling for age, sex, race/ethnicity, body mass index, history of cigarette smoking, prior-year healthcare utilization across all settings, Charlson comorbidity index, and median household income within cases’ census tract according to the categorization scheme indicated in Table 1. In addition, nirmatrelvir-ritonavir receipt is defined as a time-varying exposure. Missing values were addressed via multiple imputation, with results pooled across five pseudo-dataset replicates.
cAcute respiratory infection diagnosis codes are presented in Table S6.