Epidemiological characteristics and quarantine assessment of imported international COVID-19 cases, March to December 2020, Chengdu, China.

International flights have accelerated the global spread of Coronavirus Disease 2019 (COVID-19). Determination of the optimal quarantine period for international travelers is crucial to prevent the local spread caused by imported COVID-19 cases. We performed a retrospective epidemiological study using 491 imported COVID-19 cases in Chengdu, China, to describe the characteristic of the cases and estimate the time from arrival to confirmation for international travelers using nonparametric survival methods. Among the 491 imported COVID-19 cases, 194 (39.5%) were asymptomatic infections. The mean age was 35.6 years (SD = 12.1 years) and 83.3% were men. The majority (74.1%) were screened positive for SARS-CoV-2, conducted by Chengdu Customs District, the People's Republic of China. Asymptomatic cases were younger than presymptomatic or symptomatic cases (P < 0.01). The daily number of imported COVID-19 cases displayed jagged changes. 95% of COVID-19 cases were confirmed by PT-PCR within 14 days (95% CI 13-15) after arriving in Chengdu. A 14-day quarantine measure can ensure non-infection among international travelers with a 95% probability. Policymakers may consider an extension of the quarantine period to minimize the negative consequences of the COVID-19 confinement and prevent the international spread of COVID-19. Nevertheless, the government should consider the balance between COVID-19 and socioeconomic development, which may cause more serious social and health crises.

Estimating the impact of non-pharmaceutical interventions against COVID-19 on mumps incidence in Sichuan, China.

BACKGROUND: A series of social and public health measures have been implemented to contain coronavirus disease 2019 (COVID-19) in China. We examined the impact of non-pharmaceutical interventions against COVID-19 on mumps incidence as an agent to determine the potential reduction in other respiratory virus incidence. METHODS: We modelled mumps incidence per month in Sichuan using a seasonal autoregressive integrated moving average (ARIMA) model, based on the reported number of mumps cases per month from 2017 to 2020. RESULTS: The epidemic peak of mumps in 2020 is lower than in the preceding years. Whenever compared with the projected cases or the average from corresponding periods in the preceding years (2017-2019), the reported cases in 2020 markedly declined (P < 0.001). From January to December, the number of mumps cases was estimated to decrease by 36.3% (33.9-38.8%), 34.3% (31.1-37.8%), 68.9% (66.1-71.6%), 76.0% (73.9-77.9%), 67.0% (65.0-69.0%), 59.6% (57.6-61.6%), 61.1% (58.8-63.3%), 49.2% (46.4-52.1%), 24.4% (22.1-26.8%), 30.0% (27.5-32.6%), 42.1% (39.6-44.7%), 63.5% (61.2-65.8%), respectively. The total number of mumps cases in 2020 was estimated to decrease by 53.6% (52.9-54.3%). CONCLUSION: Our study shows that non-pharmaceutical interventions against COVID-19 have had an effective impact on mumps incidence in Sichuan, China.

Severe Acute Respiratory Syndrome Coronavirus 2 Nucleocapsid Protein in the Ocular Tissues of a Patient Previously Infected With Coronavirus Disease 2019.

Importance: Coronavirus disease 2019 (COVID-19) has been recognized as a pandemic by the World Health Organization. Whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can also infect tissues besides the respiratory system, such as the ocular tissues, remains unclear. Objective: To determine whether SARS-CoV-2 exists intracellularly in the ocular tissues of a patient previously infected with COVID-19. Design, Setting, and Participants: This case study analyzed a patient previously infected with COVID-19 who had an acute glaucoma attack during her rehabilitation. Plasma samples and tissue specimens, including ones from the conjunctiva, anterior lens capsular, trabecular meshwork, and iris, were collected during phacoemulsification and trabeculectomy surgery. Specimens from another patient who had glaucoma but not COVID-19 were used as a negative control. Main Outcomes and Measures: Specimens were analyzed using hematoxylin-eosin staining. The nucleocapsid protein antigen of SARS-CoV-2 was measured in the conjunctiva, trabecular meshwork, and iris using immunofluorescence and immunohistochemistry. The expression of angiotensin-converting enzyme 2 receptor on the conjunctiva was measured using immunohistochemistry. Results: The patient with a previous COVID-19 infection was female and 64 years old, and the control patient without a COVID-19 infection history was male and 61 years old. The nucleocapsid protein antigen of SARS-CoV-2 was detected on the cells of the conjunctiva, trabecular, and iris of the patient infected with COVID-19 but not in the control participant, while angiotensin-converting enzyme 2 receptor proteins were detected on the conjunctiva of both patients. Conclusions and Relevance: The nucleocapsid protein antigen of SARS-CoV-2 existed intracellularly in the ocular tissues of a patient previously infected with COVID-19. Thus, SARS-CoV-2 can also infect ocular tissues in addition to the respiratory system.