There has been much recent interest in screening populations for an infectious disease. Here, we present a stochastic-control model, wherein the optimum screening policy is provably difficult to find, but wherein Thompson sampling has provably optimal performance guarantees in the form of Bayesian regret. Thompson sampling seems applicable especially to diseases, for which we do not understand the dynamics well, such as to the super-spreading COVID-19.

This is an article by Gabriel Leung, Dean of Medicine at Hong Kong University Medical Center and Malik Peiris Professor at the University Hong Kong 1) COVID vaccines are needed, even if they have minimal impact on transmission 2) COVID vaccines may not help us achieve herd immunity 3) COVID vaccine trials primarily assess prevention of virologically confirmed disease - not infection or transmission 4) an "effective" vaccine confers protection from disease but might not reduce spread 5) if COVID vaccines are effective in reducing morbidity & mortality in high-risk groups, they would have an important role, irrespective of impact on transmission and population immunity 6) if high-risk populations can be shielded by vaccination, COVID control measures could be recalibrated 7) the idea that COVID vaccine-induced population immunity will allow a return to normalcy may be based on false assumptions 8) no country will be truly safe until the entire world is vaccinated. This new study from Akiko Iwasaki, PhD and colleagues at Yale University offers the first clear evidence that COVID can invade brain cells 1) 40-60% of hospitalized COVID patients experience neurological complications including nerve damage and stroke 2) this study suggests that COVID in the brain may be more lethal than the respiratory infection caused by COVID 3) COVID hijacks brain cells to make copies of itself then exploits the brain cells' machinery to multiply 4) then COVID chokes off oxygen to adjacent brain cells causing them to die 5) a few days into the infection there is a dramatic decrease the number of synapses (the connections between neurons in the brain) 6) the researchers didn't find any evidence of an immune response to remedy this problem. It's a silent infection with evasion mechanisms 7) some people may be susceptible because of their genetic background or high viral load. Researchers used Summit Supercomputer to analyze 2.5 billion genetic combinations from COVID; then they made the Bradykinin Hypothesis 1) it took Summit 1 week to run the numbers. These high-powered microscopic images show very high viral loads of SARS-CoV-2 on human respiratory surfaces ready to spread the virus 1) Camille Ehre PhD and colleagues at UNC Chapel Hill School of Medicine generated these microscopic images showing very high viral loads of SARS-CoV-2.

In late 2019, China reported a cluster of atypical pneumonia cases of unknown etiology in Wuhan. The causative agent was identified as a new betacoronavirus, called severe acute respiratory syndrome–coronavirus 2 (SARS-CoV-2), that causes coronavirus disease 2019 (COVID-19) (1). The virus rapidly spread across the globe and caused a pandemic. Sequencing of the viral genome allowed for the development of nucleic acid–based tests that have since been widely used for the diagnosis of acute (current) SARS-CoV-2 infections (2). Development of serological assays, which measure the antibody responses induced by SARS-CoV-2 infection (past but not current infections), took longer.

South Korea's infectious disease experts said Thursday that dead virus fragments were the likely cause of over 260 people here testing positive again for the novel coronavirus days and even weeks after marking full recoveries. Oh Myoung-don, who leads the central clinical committee for emerging disease control, said the committee members found little reason to believe that those cases could be COVID-19 reinfections or reactivations, which would have made global efforts to contain the virus much more daunting. "The tests detected the ribonucleic acid of the dead virus," said Oh, a Seoul National University hospital doctor, at a press conference Thursday held at the National Medical Center. He went on to explain that in PCR tests, or polymerase chain reaction tests, used for COVID-19 diagnosis, genetic materials of the virus amplify during testing, whether it is from a live virus or just from fragments of dead virus cells that can take months to clear from recovered patients. The PCR tests cannot distinguish whether the virus is alive or dead, he added, and this can lead to false positives.