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Long-term severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shedding was observed from the upper respiratory tract of a female immunocompromised individual with chronic lymphocytic leukemia and acquired hypogammaglobulinemia. Shedding of infectious SARS-CoV-2 was observed up to 70 days, and of genomic and subgenomic RNA up to 105 days, after initial diagnosis. The infection was not cleared after the first treatment with convalescent plasma, suggesting a limited effect on SARS-CoV-2 in the upper respiratory tract of this individual. Several weeks after a second convalescent plasma transfusion, SARS-CoV-2 RNA was no longer detected. We observed marked within-host genomic evolution of SARS-CoV-2 with continuous turnover of dominant viral variants. However, replication kinetics in Vero E6 cells and primary human alveolar epithelial tissues were not affected. Our data indicate that certain immunocompromised individuals may shed infectious virus longer than previously recognized. Detection of subgenomic RNA is recommended in persistently SARS-CoV-2-positive individuals as a proxy for shedding of infectious virus., Graphical Abstract, Highlights • Persistent SARS-CoV-2 infection and shedding in immunocompromised individual • Infectious SARS-CoV-2 isolated up to 70 days after diagnosis • Observed within-host genetic variation with continuous turnover of viral variants • SARS-CoV-2 isolates from the individual do not display altered replication, This case study describes a female immunocompromised individual with chronic lymphocytic leukemia and acquired hypogammaglobulinemia who became persistently infected with SARS-CoV-2. Although asymptomatic throughout the course of infection, she demonstrated prolonged shedding of infectious SARS-CoV-2 virus and RNA. This study demonstrates that certain individuals may remain infectious for prolonged periods of time and highlights the need for further studies to understand risk factors for prolonged infectious SARS-CoV-2 shedding.

Long-term SARS-CoV-2 shedding was observed from the upper respiratory tract of an immunocompromised patient with chronic lymphocytic leukemia and acquired hypogammaglobulinemia. Shedding of SARS-CoV-2 genomic and subgenomic RNA was observed up to 105 days, and infectious virus up to 70 days past the initial diagnosis. The infection was not cleared after a first treatment with convalescent plasma, suggesting limited impact on SARS-CoV-2 in the upper respiratory tract. SARS-CoV-2 RNA was no longer detected several weeks after a second transfusion of convalescent plasma. There was marked within-host genomic evolution of SARS-CoV-2, with continuous turnover of dominant viral variants. However, replication kinetics in VeroE6 cells and primary human alveolar epithelial tissues were not affected. Our data indicate that certain immunocompromised patients may shed infectious virus for longer durations than previously recognized. Detection of of subgenomic RNA is recommended in persistently SARS-CoV-2 positive individuals as a proxy for shedding of infectious virus. Funding: This work was supported by the Intramural Research Program of the National Institute of Allergy and Infectious Diseases (NIAID). T.A.B. is supported by the Medical Research Council UK (MR/S007555/1). The Wellcome Centre for Human Genetics is supported by Wellcome Centre grant 203141/Z/16Z. Conflict of Interest: The authors declare no competing interests.

With the contemporary improvements in intelligent transportation systems, automatic car License Plate Detection and Recognition (LPDR) has involved extensive research interests. It has a variety of potential applications in security and traffic control, and much work has been completed on the subject of LPDR. But, majority of prevailing procedures work well either at measured circumstances or with sophisticated image capture systems. It is still a challenging task to read license plates precisely in an open environment. The problem exists in extreme assortment in pattern of characters, such as dissimilar sizes, letterings, misrepresentation, obstruction or blurring, as well as high intricate backgrounds, similar to the common fonts in boards of shops, windows, handrails or construction blocks. In this study, a hybrid methodology has been established in recognizing license plates of candidates in a specific area. This research proposes a technique called kernel density function along with the binary technique that has been utilized for pre-processing. By means of the filtered binary value of the image, the position of car plate can be found by multiplying the binary value and original value of the image. The proposed method outperforms advanced techniques by a huge margin concerning about accuracy in detection as well as efficiency of run-time. The proposed method achieved 98.1 % accuracy to detect the License Plate (LP) and the computation cost is about 0.452 s.