Universal two-dimensional labelled probe-mediated melting curve analysis based on multiplex PCR for rapid typing of Plasmodium in a single closed tube.

Currently, malaria is still one of the major public health problems commonly caused by the four Plasmodium species. The similar symptoms of malaria and the COVID-19 epidemic of fever or fatigue lead to frequent misdiagnosis. The disadvantages of existing detection methods, such as time-consuming, costly, complicated operation, need for experienced technicians, and indistinguishable typing, lead to difficulties in meeting the clinical requirements of rapid, easy, and accurate typing of common Plasmodium species. In this study, we developed and optimized a universal two-dimensional labelled probe-mediated melting curve analysis (UP-MCA) assay based on multiplex and asymmetric PCR for rapid and accurate typing of five Plasmodium species, including novel human Plasmodium, Plasmodium knowlesi (Pk), in a single closed tube following genome extraction. The assay showed a limit of detection (LOD) of 10 copies per reaction and could accurately distinguish Plasmodium species from intra-plasmodium and other pathogens. Additionally, we proposed and validated different methods of fluorescence quenching and tag design for probes that are suitable for UP-MCA assays. Moreover, the clinical performance of the Plasmodium UP-MCA assay using a base-quenched universal probe was evaluated using 226 samples and showed a sensitivity of 100% (164/164) and specificity of 100% (62/62) at a 99% confidence interval, with the microscopy method as the gold standard. In summary, the UP-MCA assay showed excellent sensitivity, specificity, and accuracy for genotyping Plasmodium species spp. Additionally, it facilitates convenient and rapid Plasmodium detection in routine clinical practice and has great potential for clinical translation.

The patterns and management of fracture patients under COVID-19 outbreak in China.

BACKGROUND: Currently, the perioperative care of fracture patients is compromised due to the outbreak of COVID-19 in China and the world. This study aims to assess the clinical features of fracture patients at our hospital during the COVID-19 outbreak and formulate the medical steps to ensure the effective treatment of fracture patients with minimal risk of infection to healthcare workers. METHODS: One hundred twelve patients with different fractures that were admitted to the orthopedics department of our hospital from January 24 to March 9 in 2020 were reviewed. Data including age, gender, injury location, admission time, operation time, discharge time were compared with fracture patients from the same period in 2019. RESULTS: Compared to the same period in 2019, there is a 42% decrease in the number of fracture patients in 2020. Specifically, the incidences of forearm, thigh, hand, and foot fractures have increased during the COVID-19 outbreak, while other parts are less affected. The time from injury to hospitalization, the surgery wait time and time of discharge after surgery for patients with hip fractures were 2.9±7.1, 2.0±1.7 and 7.7±4.0 days respectively in 2019, which changed to 2.0±5.0, 4.5±4.0 and 10.6±4.2 days in 2020. Following the orthopedic treatment regimen followed at our hospital, all patients had non-life-threatening limb fractures. Six patients were operated in a negative pressure room, and emergency screening was completed for six patients. No patients were positive for COVID-19, and all were discharged safely without infection or other serious complications. CONCLUSIONS: Hip fractures are highly prevalent during this epidemic. However, mandatory screening delays surgery by more than 48 hours. The orthopedic department should prioritize screening of emergency patients to minimize the risk of infection among other patients and medical personnel.