Two doses of Pfizer/BioNTech BNT162b2 mRNA vaccine elicit robust severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-neutralizing antibodies with frequent adverse events. Here, by applying a high-dimensional immune profiling on 92 vaccinees, we identify six vaccine-induced immune dynamics that correlate with the amounts of neutralizing antibodies, the severity of adverse events, or both. The early dynamics of natural killer (NK)/monocyte subsets (CD16⁺ NK cells, CD56^high NK cells, and non-classical monocytes), dendritic cell (DC) subsets (DC3s and CD11c⁻ Axl⁺ Siglec-6⁺ [AS]-DCs), and NKT-like cells are revealed as the distinct cell correlates for neutralizing-antibody titers, severity of adverse events, and both, respectively. The cell correlates for neutralizing antibodies or adverse events are consistently associated with elevation of interferon gamma (IFN-γ)-inducible chemokines, but the chemokine receptors CCR2 and CXCR3 are expressed in distinct manners between the two correlates: vaccine-induced expression on the neutralizing-antibody correlate and constitutive expression on the adverse-event correlate. The finding may guide vaccine strategies that balance immunogenicity and reactogenicity.

Background: To control COVID-19 pandemic is of critical importance to the global public health. To capture the prevalence in an accurate and timely manner and to understand the mode of nosocomial infection are essential for its preventive measure. Methods: We recruited 685 healthcare workers (HCW’s) at Tokyo Shinagawa Hospital prior to the vaccination with COVID-19 vaccine. Sera of the subjects were tested by assays for the titer of IgG against S protein’s receptor binding domain (IgG (RBD)) or IgG against nucleocapsid protein (IgG (N)) of SARS-CoV-2. Together with PCR data, the positive rates by these methods were evaluated. Results: Overall positive rates among HCW’s by PCR, IgG (RBD), IgG (N) with a cut-off of 1.4 S/C (IgG (N)_1.4), and IgG (N) with a cut-off of 0.2 S/C (IgG (N)_0.2) were 3.5%, 9.5%, 6.1%, and 27.7%, respectively. Positive rates of HCW’s working in COVID-19 ward were significantly higher than those of HCW’s working in non-COVID-19 ward by all the four methods. Concordances of IgG (RBD), IgG (N)_1.4, and IgG (N)_0.2 against PCR were 97.1%, 71.4%, and 88.6%, respectively. By subtracting the positive rates of PCR from that of IgG (RBD), the rate of overall silent infection and that of HCW’s in COVID-19 ward were estimated to be 6.0% and 21.1%, respectively. Conclusions: For the prevention of nosocomial infection of SARS-CoV-2, identification of silent infection is essential. For the detection of ongoing infection, periodical screening with IgG (RBD) in addition to PCR would be an effective measure. For the surveillance of morbidity in the population, on the other hand, IgG (N)_0.2 could be the most reliable indicator among the three serological tests.

Bacillus Calmette-Guerin (BCG) intravesical injections are used as adjuvant therapy for superficial bladder cancer. We report a case of a 78-year-old man who developed disseminated M. bovis BCG disease mimicking miliary tuberculosis early after BCG intravesical infusion. He started coughing after receiving three rounds of BCG for superficial bladder tumors, following transurethral resection of the tumors, approximately one month after initiation. Computerized tomography (CT) images showed diffuse nodular shadows in the bilateral lung fields with a random pattern. Consequently, disseminated BCG disease was diagnosed. Treatment with isoniazid, rifampicin, and ethambutol was initiated. Nine months after initiating treatment, CT showed the disappearance of the miliary shadows. We also discussed 77 cases of suspected BCG infection and the requests for Mycobacterium bovis BCG identification at our institution from 2017 to October 2022. Of these, 76 cases were M. bovis BCG, and 1 case was M. tuberculosis. Since M. tuberculosis can be identified in some patients with suspected BCG infection, it is crucial to distinguish between the two based on pathogenicity.