Efficacy of rapid antigen self-testing for SARS-CoV-2 screening:Real-world evidence from a prospective cohort study

Antigen rapid diagnostic tests(Ag-RDTs)have been considered and implemented as an important diagnostic and screening tool to identify SARS-CoV-2 infections in community settings.1 Ag-RDTs are less sensitive,particularly in asymptomatic populations,compared with laboratorybased viral nucleic acid amplification tests(NAATs)such as reverse transcription polymerase chain reaction(RT-PCR).2 However,taking into account the facts that Ag-RDTs are effective for identifying most contagious individuals,they are faster and less expensive than RT-PCR,as well as that RT-PCR could produce positive results for weeks to months after the infection,2 WHO recommends Ag-RDTs be offered as COVID-19 self-testing for screening purposes in addition to professionally administered testing services regardless of the community transmission level.

Patients with SARS-CoV-2 and HBV coinfection are at risk of greater liver injury

To date,it remains unclear if severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)co-infection exacerbates liver injury in patients with chronic hepatitis B virus(HBV)infection.In this study,we present a retrospective study of 133 hospitalized confirmed mild coronavirus disease 2019(COVID-19)cases,including 116 patients with COVID-19 with negative serum hepatitis B antigen and 17 HBV inactive carriers with COVID-19.We found that there were no significant differences for the discharge rate or duration of hospitalization be-tween the two groups.However,inactive HBV carriers with SARS-CoV-2 co-infection are at a higher risk of abnormal liver function tests.The enhanced liver injury induced by SARS-CoV-2 and HBV co-infection was identified as the hepatocyte type rather than the cholangiocyte type.Moreover,the inflammatory response,including abnormal lactate dehydrogenase,D-dimer and interleukin-6 production,may contribute to this injury following SARS-CoV-2 co-infection.Collectively,SARS-CoV-2 and HBV co-infection exacerbates liver function of the pa-tients with COVID-19.

Dynamics of neutralizing antibody responses to SARS-CoV-2 in patients with COVID-19: an observational study

Our understanding of the protective immunity,particularly the long-term dynamics of neutralizing antibody(NAbs)response to SARS-CoV-2,is currently limited.We enrolled a cohort of 545 COVID-19 patients from Hubei,China,who were followed up up to 7 months,and determined the dynamics of NAbs to SARS-CoV-2 by using a surrogate virus neutralization test(sVNT).In our validation study,sVNT IC50 titers and the neutralization rate measured at a single dilution(1:20)were well correlated with FRNT titers(r=0.85 and 0.84,respectively).The median time to seroconversion of NAbs was 5.5 days post onset of symptoms.The rate of positive sVNT was 52% in the first week,reached 100% in the third week,and remained above 97% till 6 months post onset.Quantitatively,NAbs peaked in the fourth week and only a quarter of patients had an estimated peak titer of>1000.NAbs declined with a half-time of 61 days(95%CI:49-80 days)within the first two months,and the decay deaccelerated to a half-time of 104 days(95%CI:86-130 days)afterward.The peak levels of NAbs were positively associated with severity of COVID-19 and age,while negatively associated with serum albumin levels.The observation that the low-moderate peak neutralizing activity and fast decay of NAbs in most naturally infected individuals called for caution in evaluating the feasibility of antibody-based therapy and vaccine durability.NAbs response positively correlated with disease severity,warning for the possibility of repeat infection in patients with mild COVID-19.

Durability of Hepatitis B surface antigen seroclearance in patients experienced nucleoside analogs or interferon monotherapy: A real-world data from Electronic Health Record

Little is known about the difference in durability of HBsAg seroclearance induced by nucleoside analogs (NAs) or by interferon (IFN). A real-world, retrospective cohort study was conducted. Patients were assigned into two groups: NAs monotherapy-induced HBsAg seroclearance subjects and IFN monotherapy induced-HBsAg seroclearance subjects. A total of 198 subjects, comprised by 168 NAs monotherapy-induced and 30 IFN monotherapy-induced, who achieved HBsAg seroclearance were included in this study. The one-year probabilities of confirmed HBsAg seroclearance were significantly different in patients with NAs monotherapy and IFN monotherapy (0.960 (with 95% CI 0.922–0.999) vs. 0.691 (with 95% CI 0.523–0.913), log-rank-P = 4.04e-4). 73.3% (11 of 15) HBsAg recurrence occurred within one year after HBsAg seroclearance. The one-year probabilities of confirmed HBsAg seroclearance were higher in IFN monotherapy patients with anti-HBs than in IFN monotherapy patients without anti-HBs (0.839 (with 95% CI 0.657–1.000) vs. 0.489 (with 95% CI 0.251–0.953), log-rank test, P = 0.024). Our study thus provided novel insights into the durability of HBsAg seroclearance induced by NAs or IFN monotherapy. In particular, the HBsAg seroreversion rate was relatively high in IFN monotherapy subjects. The presence of anti-HBs was significantly correlated with a longer durability of functional cure induced by IFN treatment. And one-year follow-up in HBsAg seroclearance achieved individuals is proper for averting HBsAg seroreversion and other liver disease.