Detection characteristics of the virus during school influenza outbreaks in Linyi City / 中国学校卫生

Objective@#To analyze the characteristics of influenza virus detection in an influenza outbreak in schools, so as to provide a strategic basis for the treatment of influenza outbreaks in schools.@*Methods@#A total of 1 702 samples were collected from 52 school influenza outbreaks reported in Linyi City in 2021-2022. The samples were divided into 3 types according to different symptoms during the management of the epidemic [group A:influenzalike illness (ILI) group; group B:mild illness group; group C:close contacts group]. Rt-PCR was used to detect influenza virus nucleic acid in the collected samples. The detection rate of influenza virus in the outbreaks was analyzed by χ2 test.@*Results@#In total, 1 071 samples (62.93%) tested positive for influenza virus nucleic acid. Among them, 610 out of 726 samples (84.02%) were detected in group A, while 331 out of 634 samples (52.21%) were detected in group B. In group C, 130 out of 342 samples (38.01%) tested positive. The differences were statistically significant (χ2=260.71, P<0.01). In group A, males had a detection rate of 80.83% for influenza virus nucleic acid, compared to 91.36% for females. For group B, the rates were 53.31% for males and 50.87% for females. In group C, males had a rate of 30.72%, while females had a rate of 43.92%. Statistical significance for gender differences was observed only in groups A and C (χ2=12.67, 6.25, P<0.05). According to the days of onset, the detection rates of influenza virus nucleic acid among patients with onset 0-6 days were 56.30%, 74.49%, 89.35%, 86.23%, 69.67%, 62.75%, 34.33%, respectively, and the difference was statistically significant (χ2=128.27, P<0.01).@*Conclusions@#Mild cases and close contacts are likely key factors contributing to the prolonged emergence of new cases within classrooms during school influenza outbreaks. The progression of influenza symptoms is related to the risk of transmission.

Eosinophil: A Nonnegligible Predictor in COVID-19 Re-Positive Patients.

Although vaccine resources are being distributed worldwide, insufficient vaccine production remains a major obstacle to herd immunity. In such an environment, the cases of re-positive occurred frequently, and there is a big controversy regarding the cause of re-positive episodes and the infectivity of re-positive cases. In this case-control study, we tracked 39 patients diagnosed with COVID-19 from the Jiaodong Peninsula area of China, of which 7 patients tested re-positive. We compared the sex distribution, age, comorbidities, and clinical laboratory results between normal patients and re-positive patients, and analysed the correlation between the significantly different indicators and the re-positive. Re-positive patients displayed a lower level of serum creatinine (63.38 ± 4.94 U/L vs. 86.82 ± 16.98 U/L; P =0.014) and lower albumin (34.70 ± 5.46 g/L vs. 41.24 ± 5.44 g/L, P =0.039) at the time of initial diagnosis. In addition, two positive phases and the middle negative phase in re-positive patients with significantly different eosinophil counts (0.005 ± 0.005 × 109/L; 0.103 ± 0.033 × 109/L; 0.007 ± 0.115 × 109/L; Normal range: 0.02-0.52 × 109/L). The level of eosinophils in peripheral blood can be used as a marker to predict re-positive in patients who once had COVID-19.

Epidemiology Characteristics of Human Coxsackievirus A16 and Enterovirus 71 Circulating in Linyi, China, from 2009 to 2017.

In China, a rapid expansion of hand, foot, and mouth disease (HFMD) outbreaks has occurred since 2004, and HFMD has become an important issue in China. There are more than 20 types of enterovirus causing HFMD, of which coxsackievirus A16 (CA16) and enterovirus 71 (EV71) are the most common. This study aimed to analyze the epidemiological characteristics of HFMD caused by EV71 and CA16 in Linyi, Shandong province, China, from 2009 to 2017. The stool specimens and throat samples of 5,324 patients with HFMD were obtained for nucleic acid detection of enterovirus. A total of 4,040 HFMD cases were caused by viral pathogens. Of these, 1,706 cases were positive for EV71 and 1,266 were positive for CA16. These 2 virus strains appeared alternately in Linyi city. The incidence of EV71-positive and CA16-positive cases was highest in children aged 0-5 years, with male patients being predominant. This outbreak of HMFD caused by EV71 and CA16 mainly occurred between April and July and appeared alternately between the years 2011 and 2017. These results demonstrated that the epidemiological analysis of EV71 and CA16 can provide a scientific basis for the prevention and treatment of the disease.