Coronavirus disease 2019 (COVID-19) emerged in Wuhan, China, in December 2019 and has spread globally with sustained human-to-human transmission outside China. 1,2 To control the spread of COVID-19 and isolate patients as early as possible, the Chinese government requested that close contacts of individuals with COVID-19 must be screened for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. During the screening process, we found some patients whose test results were positive for SARS-CoV-2 but who had no symptoms or signs throughout the course of the disease. Considering that little is known about the differences of clinical features and prognosis between patients who were asymptomatic vs those who were symptomatic, 3,4 this case series aimed to describe the clinical characteristics of patients with SARS-CoV-2 infection confirmed by reverse transcription-polymerase chain reaction (RT-PCR) from 26 transmission cluster series in Wuhan,

2 6 Sweden 2 7 2 8 Abstract = 186 words, Main text = 1722 words, Figures =2. Abstract 3 0 Objectives: Comorbidities have significant indications for the disease outcome of COVID-19, 3 1 however which underlying diseases that contribute the most to aggravate the conditions of 3 2 COVID-19 patients is still largely unknown. SARS-CoV-2 viral clearance is a golden standard 3 3 for defining the recovery of COVID-19 infections. To dissect the underlying diseases that 3 4 could impact on viral clearance, we enrolled 106 COVID-19 patients who were hospitalized in 3 5 Methodology: We comprehensively analyzed demographic, clinical and laboratory data, as 3 8 well as patient treatment records. Survival analyses with Kaplan-Meier and Cox regression 3 9 modelling were employed to identify factors influencing the viral clearance negatively. 4 0 Results: We found that increasing age, male gender, and angiotensin-converting enzyme 2 4 1 (ACE2) associated factors (including hypertension, diabetes, and cardiovascular diseases) 4 2 adversely affected the viral clearance. Furthermore, analysis by a random forest survival 4 3 model pointed out hypertension, cortisone treatment, gender, and age as the four most 4 4 important variables. 4 5 Conclusions: We conclude that patients at old age, males, and/or having diseases 4 6 associated with high expression of ACE2 will have worse prognosis during a COVID-19 4 7 infections. 4 8 4 9

Recent transmission of M. tuberculosis, including MDR strains, contributes substantially to tuberculosis disease in China. Sputum smear-negative cases were responsible for at least 30% of the secondary cases. Interventions to reduce the transmission of M. tuberculosis should be implemented in China.

BackgroundMultidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) are global health problems. We sought to determine the characteristics, prevalence, and relative frequency of transmission of MDR and XDR TB in Shanghai, one of the largest cities in Asia.MethodsTB is diagnosed in district TB hospitals in Shanghai, China. Drug susceptibility testing for first-line drugs was performed for all culture positive TB cases, and tests for second-line drugs were performed for MDR cases. VNTR-7 and VNTR-16 were used to genotype the strains, and prior treatment history and treatment outcomes were determined for each patient.ResultsThere were 4,379 culture positive TB cases diagnosed with drug susceptibility test results available during March 2004 through November 2007. 247 (5.6%) were infected with a MDR strain of M. tuberculosis and 11 (6.3%) of the 175 MDR patients whose isolate was tested for susceptibility to second-line drugs, were XDR. More than half of the patients with MDR and XDR were newly diagnosed and had no prior history of TB treatment. Nearly 57% of the patients with MDR were successfully treated.DiscussionTransmission of MDR and XDR strains is a serious problem in Shanghai. While a history of prior anti-TB treatment indicates which individuals may have acquired MDR or XDR TB, it does not accurately predict which TB patients have disease caused by transmission of MDR and XDR strains. Therefore, universal drug susceptibility testing is recommended for new and retreatment TB cases.