ABSTRACT
Objective:To discover the epidemiological characteristics and clinical manifestations of Nontyphoidal Salmonella(NTS) infection in children suffering from diarrhea in Guangzhou, and to provide references for the prevention and treatment of salmonella infection. Methods:A total of 570 diarrhea children and 296 non-diarrhea controls were collected with stratified sampling from three districts of Guangzhou Women and Children′s Medical Center from January 2019 to December 2019. Through bacterial culture, corresponding colonies were selected and Salmonella diagnostic serum was applied for preliminary serum diagnosis, and then systemic biochemical method was adopted for diagnosis. A structured questionnaire was conducted to record the demographic information and clinical symptoms from each subject. Results:The detection rate of NTS was 6.67% (38/570 cases, 95% CI: 4.90%-9.02%) in children with diarrhea, and 1.01% (3/296 cases, 95% CI: 0.34%-2.93%) in children without diarrhea. There were statistically differences in NTS detection rate between children with diarrhea and the control ( χ2=13.805, P<0.05, OR=6.976, 95% CI: 2.135-22.796). There were no significant differences in NTS detection rate between male and female children with diarrhea ( χ2=0.395, P>0.05, OR=1.254, 95% CI: 0.619-2.541). The detection rate of NTS was 5.30% (22/416 cases, 95% CI: 3.52%-7.88%) in children younger than 2 years old, and was 10.40% (16/154 cases, 95% CI: 6.50%-15.21%) in children over 2 years old. There were statistically differences ( χ2=4.700, P<0.05, OR=2.076, 95% CI: 1.060-4.068) between the younger and the older groups.The detection rate of NTS was 5.40% (25/460 cases, 95% CI: 3.70%-7.89%) for children with diarrhea in outpatient department and 11.80% (13/110 cases, 95% CI: 7.04 %-19.18%) for children with diarrhea in inpatient department, with statistically significant differences ( χ2=5.813, P<0.05, OR=2.332, 95% CI: 1.152-4.721). The detection rate of NTS diarrhea in children was 4.60% (10/217 cases, 95% CI: 2.52%-8.28%) in spring, 8.50% (12/141 cases, 95% CI: 4.93%-14.29%) in summer, 9.60% (15/144 cases, 95% CI: 6.41%-16.48%) in autumn and 1.50% (1/168 cases, 95% CI: 0.11%-3.30%) in winter, respectively, with statistically differences among the four seasons( χ2=9.404, P<0.05). There were significant differences in most common clinical symptoms of fever, vomiting, abdominal pain, bloody stool and pasty stool between NTS positive and negative children(all P<0.05). Salmonella enteritis is the main type, and Salmonella typhimurium is the second type. Conclusions:NTS is one of the most important bacterial pathogens and leads to diarrhea in children in Guangzhou city, without differences in gender.Children over 2 years old are more likely to suffer from NTS infection.High incidence is in autumn.The most common clinical symptoms include fever, vomiting, abdominal pain, bloody stool and pasty stool. Salmonella enteritis is the main type, and Salmonella typhimurium is the second type.Laboratory tests can provide references for the diagnosis and treatment of NTS-related diarrhea.
ABSTRACT
Rolling circle amplification is a rapid, sensitive and isothermal single-stranded DNA amplification technique that can be used with staining or probes to amplify the detection signal. This technology has been widely used in biological detection and other aspects. The present paper introduces how to design rolling circle amplification, summarize its application in the detection of pathogens, nucleic acid tumor markers, proteins, biological small biomolecules, and viruses in recent years and prospects for future development.