Comparison of self-reported symptoms in COVID-19 patients who had or had not previously received COVID-19 mRNA vaccination.

Although mRNA coronavirus disease 2019 (COVID-19) vaccines have been reported for high effectiveness against symptoms, it remains unclear whether post-vaccination infections are less symptomatic than infections in vaccine-naive individuals. We included patients with COVID-19 diagnosed by polymerase chain reaction tests during Japan's alpha and delta variant epidemics. COVID-19 symptoms at approximately 4 weeks were compared based on COVID-19 vaccination status. In total, 398 cases (372 symptomatic and 26 asymptomatic; 286 unvaccinated, 66 vaccinated with one dose, and 46 with two doses) were analyzed. The most common symptoms were fever (78.4%), fatigue (78.4%), cough (74.4%), loss of taste or smell (62.8%), and headache (59.8%). Post-vaccination infections were significantly less likely to be symptomatic. Possible confounder-adjusted odds ratios of two vaccine doses against fatigue, dry eyes and mouth, insomnia, fever, shortness of breath, unusual muscle pains, and loss of taste or smell were 0.18 (95% confidence interval [CI]: 0.09-0.38), 0.22 (95% CI: 0.08-0.59), 0.33 (95% CI: 0.14-0.80), 0.31 (95% CI: 0.15-0.63), 0.36 (95% CI: 0.16-0.76), 0.40 (95% CI: 0.19-0.82), and 0.44 (95% CI: 0.22-0.87), respectively. Post-vaccination infections after two mRNA COVID-19 vaccine doses show milder and fewer symptoms than infections in unvaccinated patients, highlighting the effectiveness of vaccination.

Real-World Effectiveness of the mRNA COVID-19 Vaccines in Japan: A Case-Control Study.

The real-world effectiveness of the coronavirus disease 2019 (COVID-19) vaccines in Japan remains unclear. This case-control study evaluated the vaccine effectiveness (VE) of two doses of mRNA vaccine, BNT162b2 or mRNA-1273, against the delta (B.1.617.2) variant in the Japanese general population in the period June-September 2021. Individuals in close contact with COVID-19 patients were tested using polymerase chain reaction (PCR). A self-administered questionnaire evaluated vaccination status, demographic data, underlying medical conditions, lifestyle, personal protective health behaviors, and living environment. Two vaccine doses were reported by 11.6% of cases (n = 389) and 35.2% of controls (n = 179). Compared with controls, cases were younger and had a lower proportion who always performed handwashing for ≥20 s, a higher proportion of alcohol consumers, and a lower proportion of individuals living in single-family homes or with commuting family members. After adjusting for these confounding factors and day of PCR testing by multivariate logistic regression analysis, the VE in the period June-July (delta variant proportion 45%) was 92% and 79% in the period August-September (delta variant proportion 89%). The adjusted VE for homestay, hotel-based isolation and quarantine, and hospitalization was 78%, 77%, and 97%, respectively. Despite declining slightly, VE against hospitalization remained robust for ~3 months after the second dose. Vaccination policymaking will require longer-term monitoring of VE against new variants.

[Pulmonary alveolar proteinosis noted in a patient with thymoma].

A 74-year-old woman had general fatigue and mild fever in August 2004. Her chest X-ray showed slight ground glass opacities in the upper and middle lung fields of both lungs. Though she was prescribed antibacterial drugs, the abnormal shadows on chest X-ray did not improve. The chest CT showed ground glass opacities and reticular shadows with thickened alveolar septa (crazy-paving appearance) in both lungs, and a clearly defined mass in the anterior mediastinum. She underwent thymo-thymectomy with wedge resection of the upper lobe of the left lung. Anterior mediastinum tumor was pathologically diagnosed as thymoma. Lung biopsy demonstrated alveoli filled with SP-A positive granular materials, and we diagnosed pulmonary alveolar proteinosis. About 1 month after operation, the shadows on chest CT showed improvement. We think there might be some relationship between thymoma and pulmonary alveolar proteinosis.

[Case of chronic eosinophilic bronchiolitis associated with bronchial asthma].

A 62 year-old woman presented with diffuse, centriacinar nodular densities on chest radiography and CT, and an increase of peripheral blood eosinophils, four years after diagnosis of bronchial asthma. Diffuse panbronchiolitis was diagnosed, and was treated with erythromycin for a long period. One year later, she noticed exertional dyspnea, and her chest radiograph showed increased nodular densities. Lung biopsy under video-assisted thoracoscopy was performed, and revealed chronic bronchiolitis with eosinophilic infiltration, and focal, peribronchiolar eosinophilic infiltration in the alveolar septa and alveoli. She was treated with prednisolone, and her symptoms and nodular densities on chest radiography and CT were improved. We consider that the clinico-pathological findings of this case are consistent with those of chronic eosinophilic bronchiolitis, which has recently been reported in Japan. This case is different from previously reported ones in that eosinophilic bronchiolitis appeared in the course of bronchial asthma, suggesting the possibility that eosinophilic bronchiolitis may be accompanied with bronchial asthma or eosinophilic pneumonia.