Objective:To analyze the epidemiological and etiological characteristics of sever fever with thrombocytopenia syndrome (SFTS) cases in Henan province during 2017-2020.Methods:Descriptive epidemiology method was used to analyze the characteristics of SFTS cases in Henan during 2017-2020. Patients' sera in acute phase were collected and tested using real-time fluorescence RT-PCR. The S segment complete sequences of the isolated sever fever with thrombocytopenia syndrome virus (SFTSV) strains were amplified and homology analysis was performed to construct the phylogenetic tree.Results:A total of 1 767 SFTS cases, including 1 000 suspected cases and 767 confirmed cases, were reported in Henan during this period, and 11 cases, including 3 suspected cases and 8 confirmed cases died, the case fatality rate was 0.62% (11/1 767). The incidence decreased year by year. The cases were distributed in 28 counties of 6 cities, and 1 681 cases were reported in Xinyang, accounting for 95.13% (1 681/1 767) of the total. The cases mainly occurred from April to October, accounting for 96.10% (1 698/1 767) of the total. The incidence in males (0.38/100 000) was significantly lower than that in females (0.54/100 000) ( χ 2=54.855, P<0.001). Up to 93.44% (1 651/1 767) of the cases were aged between 40 and 84 years. Farmers accounted for 96.10% (1 698/1 767) of the total cases. One family cluster outbreak occurred in 4 years. A total of 1 110 samples were detected by Henan CDC, in which 435 were SFTS virus positive with an average positive rate of 39.19% (435/1 110). The differences in positive rates of SFTS virus among different years were significant ( χ2=25.405, P<0.001). The sequence homology of complete S segment of the 39 SFTS virus strains ranged from 94.76% to 99.82%. The genetic evolution analysis on the complete S segment of the 39 SFTS virus strains showed that 34 strains belonged to genotype A, 2 strains belonged to genotype B, and 3 strains belonged to genotype D. Conclusions:The incidence of SFTS in Henan was sporadic, and decreased year by year. SFTS had obvious regional and seasonal characteristics, and the area affected by SFTS expanded. The incidence of SFTS was high in elderly female farmers, and the positive rate of SFTS virus varied greatly in different years. The main type of SFTS virus in Henan was genotype A, but the etiological surveillance is still needed.

Objective: To understand the possible transmission route of a family cluster of COVID-19 in Zhengzhou and the potential infectivity of COVID-19 in incubation period, and provide scientific evidence for the timely control of infectious source and curb the spread of the epidemic. Methods: Epidemiological investigation was conducted for a family cluster of COVID-19 (8 cases) with descriptive epidemiological method, and respiratory tract samples of the cases were collected for the nucleic acid detection of 2019-nCoV by RT-PCR. Results: Two primary cases, which occurred on 31 January and 1 February, 2020, respectively, had a common exposure history in Wuhan. The other six family members had onsets on 30 January, 31 January, 1 February (three cases) and 3 February, 2020. Conclusions In this family cluster of COVID-19, six family members were infected through common family exposure to the 2 primary cases. Five secondary cases had onsets earlier than or on the same day as the primary cases, indicating that COVID-19 is contagious in incubation period, and the home isolation in the early phase of the epidemic might lead to the risk of family cluster of COVID-19.

Objective:To analyze data gathered from the laboratory records related to imported Dengue cases in Henan province in 2018.Methods:Suspected Dengue cases were found out through the Dengue fever surveillance network from the National infectious Disease reporting management information system. Serum samples of suspected Dengue cases were collected while case study and tested for Dengue NS1 antigen, IgM, IgG antibodies and Dengue RNA in Henan province in 2018. According to the standardized Dengue diagnosis criteria, confirmed cases were identified under the results of testing. Dengue RNA was checked by Real-time PCR genotyping and amplification of E gene in the samples being tested, before the PCR products were sequenced and analyses of homological and phylogenetic were performed.Results:In 2018, a total of 29 cases of Dengue fever was reported in Henan province, with all of which were imported cases, mainly from Southeast Asian countries and Africa. Majority of the cases were young and middle-aged farmers under 45 years old, and the number of males was significantly higher than that of females. The imported cases were dispersed in time and space. Among the 29 Dengue reported cases, 22 cases were with NS1 antigen and/or IgM positive through testing, while 6 cases were positive by detection of the Dengue virus RNA. These 6 samples with Dengue RNA were genotyped successfully, including 3 cases of Dengue virus type 1 and 3 cases of type 2. One of the Maldives import Dengue virus type 2 samples was sequenced. Result showed that the sequence belonged to the Asian Ⅰ genotype, which was most consistently similar to the Cambodia’s Dengue virus type 2 JF730046, identified in 2008.Conclusions:The incidence of imported Dengue fever cases increased significantly in Henan province in 2018, compared to that in 2017, but fortunately did not cause any local epidemics.

To study the epidemiology and etiology characteristics of first imported Chikungunya fever case in Henan province, China, 2017. The patient was confirmed by Chikungunya virus (CHIKV) infected as CHIKV ribonucleotide was continuously detected in his serum specimens. BHK-21 cell line was used for virus isolation, the strain was named CHIKV/Henan001/2017. CHIKV/Henan001/2017 belonged to genotype ECSA. The highest ribonucleotide homology sequence of highly conserved region E1 with CHIKV/Henan001/2017 was hk02 strain (99.8%), who was an imported strain to Hong Kong, China, 2016. Epidemiological information and laboratory testing confirmed it was an imported Chikungunya fever case in Henan province, 2017. No secondary case has been reported.

Objective To analyze the VP1 sequences of coxsackievirus A16(CA16) causing neu-rologic complications. Methods Clinical samples and epidemiological information were collected from pa-tients with viral encephalitis. Coxsackievirus A16 in these samples were first detected with real time RT-PCR and then isolated. RT-PCR was performed to amplify VP1 sequences and the amplified products were se-quenced. DNAStar 5.0 and Mega 5 were used for sequence analysis. All data was analyzed with SPSS statis-tical software. Results Fifteen samples were collected from 12 patients with hand, foot and mouth disease (HFMD) complicated by neurologic complications. Eight patients had the symptoms of fever, skin rash, signs of meningeal irritation and neck rigidity. No typical cluster was associated with clinical features or the time of onset. Both pharyngeal/anal swab and serum samples were collected from three patients (patient′s number:01111,01169 and 01130). The two samples collected from both 01111 and 01130 patients shared 100% similarity in nucleotide and amino acid based on VP1 sequences,while those from 01169 patient dif-fered in only one base. The 15 CA16 isolates were highly similar in VP1 gene, sharing 94.5%-100% ho-mology in nucleotide sequences and 98.0%-100% homology in amino acid sequences. These 15 isolates showed 68.5%-70.5% identities in nucleotide sequences and 90.5%-91.9% identities in amino acid se-quences with the CA16 prototype strain G10. Phylogenetic analysis revealed that based upon VP1 sequences, all of the 15 CA16 isolates grouped into genotype B subtype 1b (B1b), which was further classified into three clusters. Conclusion All of the 15 CA16 isolates causing neurologic complications belonged to B1b sub-genotype. Understanding the molecular epidemiology of CA16 would be essential for controlling morbidi-ty rates of HFMD and vaccine research.

Objective To monitor the environmental contamination with avian influenza virus (AIV) in Henan Province. Methods Environmental samples were collected every month from seven moni-toring sites in Henan from 2013 to 2017. Real-time RT-PCR method was performed to detect the nucleic acid of influenza A (Flu A), H5, H7 and H9 viruses in poultry environmental samples. Results A total of 2538 environmental samples were collected and 202 (7. 96％ ) of them were positive for Flu A nucleic acid, including 16 positive for H5 (0. 63％ ), eight positive for H7 (0. 32％ ) and 161 positive for H9 (6. 34％ ). The detection rate of Flu A increased dramatically from 2013 to 2017 except for a small fluctuation in 2015. However, H7 subtype AIV was detected only in 2015 and 2017. The highest detection rate of AIV was in February, followed by that in January. Among different environments, the highest detection rate of Flu A was in live poultry market, which was 13. 69％ , followed by that in poultry slaughtering plant (2. 58％ ) and poultry farm (0. 58％ ). The detection rates of Flu A in swab samples of poultry plucker and cutting board, stool specimens and poultry drinking water were 28. 57％ , 13. 76％ , 5. 70％ and 5. 26％ , respectively.Conclusion Contamination of H5 / H7 / H9 AIV did exist in poultry environment in Henan and was getting worse. Increasingly diversified sources and sale channels were the main causes of serious contamination of AIV. In order to effectively prevent and control human infection with AIV, live poultry in areas where human infection with AIV was confirmed should be blocked and banned to be sold to others areas.

Objective: To confirm the laboratory diagnosis of dengue bordline cases reported in Henan Province and trace its origin from molecular level in 2017. Methods: The study samples were blood samples (3-5 ml), which came from 8 suspected cases of dengue fever reported in the 2017 direct reporting system of Henan provincial infectious disease monitoring network. Meanwhile, case investigation was conducted according to National dengue fever surveillance programme. Serum were separated from blood samples and tested for Dengue NS1 antigen, IgM & IgG antibodies, and dengue RNA. According to dengue diagnosis criteria, confirmed cases were identified by testing results. Samples carried dengue RNA performed for real-time PCR genotyping and amplification of E gene. Then, the amplicons were sequenced and homological and phylogenetic analyses were constructed. Results: 8 serum samples of suspected dengue cases were collected in Henan Province, 2017. Six of them were diagnosed as dengue confirmed cases. All the dengue confirmed cases belonged to outside imported cases, 5 of them were positive by dengue RNA testing. Genotyping results showed there were 1 DENV1 case, 2 DENV2 cases and 2 DENV3 cases. A DENV2 case and a DENV3 case of this study were traced its origin successfully. The sequence of Pakistan imported DENV2 case belongs to cosmopolitan genotype, which was the most consistent with Pakistan's DENV2 KJ010186 in 2013 (identity 99.0%). The sequence of Malaysia imported DENV3 case belongs to genotype I, which was the most consistent with Singapore's DENV3 KX224276 in 2014(identity 99.0%). Conclusion The laboratory diagnosis and molecular traceability of dengue cases in Henan Province in 2017 confirmed that all cases were imported and did not cause local epidemics.

Objective: To investigate the infectious status, gene type transition and epidemiological features of rotavirus A isolated from infants and children (<59 months-of-age) in sentinel hospitals from 2008 to 2015 in Henan province, China. Methods: In total, 2 541 stool samples (each 3- 5 ml) were collected from infants and children aged less than five years in two sentinel hospitals and group A rotavirus was detected by a double antibody sandwich ELISA. Viral RNA was extracted from positive samples and G/P gene typing was performed using a two-step nested multiplex RT-PCR. Epidemiological information (including demographic information such as age, sex and clinical symptoms) was also collected from the patients and analyzed. Results: Group A rotavirus was detected in 30.9% (785/2 541) of diarrhea samples from children. The detection rate was higher in October (54.8%, 345/629) and lower in July (5%, 5/101) each year from 2008 to 2015. The group A rotavirus infection rate was higher in boys (30.6%, 451/1 476) than in girls (31.4%, 334/1 065) (χ²=0.18, P=0.664). Infection mainly occurred in 4-12 months old patients (61.3%, 481/785) (χ²=196.69, P<0.001), and the infection rate was lower in cities (26%, 258/992) compared with rural areas (34.0%, 527/1 549) (χ²=18.19, P<0.001). G typing of 785 strains of group A rotavirus revealed the following types: G1 (13.5%, 106 strains), G2 (11.1%, 87 strains), G3 (29.7%, 233 strains), and G9 (57.5%, 451 strains); P typing revealed the predominance of P[4] (11.3%, 89 strains) and P[8] (84.7%, 665 strains); gene type combinations comprised mainly G9P[8], G2P[4], G3P[8], G1P[8], respectively accounted for 52.9% (415), 9.7% (76), 17.3% (136), 11.3% (89). Gene type combinations G1 [8] and G3P[8] have been decreasing in prevalence since 2008 and G9P[8] has become the dominant gene type of group A rotavirus in Henan province. Among the group A rotavirus infection samples, the male:female infection ratio was 1.4∶1 (451/334), with no significant difference in the infection rate (χ²=0.18, P=0.664); the infection rate was higher in 4- 12 months old patients (61.3%, 481/785), with a significant difference detected between age groups (χ²=196.69, P<0.001). The rate of detection was lower in cities (26.0%, 258/992) than in rural areas (34.0%, 527/1 549) (χ²=18.19, P<0.001). Clinical analysis revealed a body temperature of below 37 degrees in 75.7% of positive cases (594 patients), 37.0- 37.5 degrees in 17.2% of cases (135 patients), 37.6-38.0 degrees in 2.0% of cases (16 patients), and above 38 degrees in 5.1% of cases (40 patients), with most cases showing no fever or a mild fever. The frequency of episodes of diarrhea among the patients was 0- 3 times (21.1%, 166 cases), 4- 6 times (65.6%, 515 cases), 7- 9 times (8.0%, 63 cases), or 10- 15 times (5.2%, 41 cases), mainly showing mild and moderate diarrhea. Vomiting also varied in frequency among the patients from no vomiting (86.9%, 682 cases), 1-2 times (11.8%, 92 cases), 3 times (6.0%, 47 cases), and more than 3 times (0.4%, 3 cases). The occurrence of dehydration varied from no dehydration (86.9%, 682 cases), mild dehydration of 1%- 5% (12.1%, 95 cases), to severe dehydration of ≥5% (1.0%, 8 cases). Conclusion A higher infection rate of group A rotavirus was detected in children younger than five years of age with acute diarrhea in sentinel hospitals in Henan province, including part-mixed infection cases. A predominance of cases was detected in the autumn, and secondly the spring of each year. Gene type G9P[8] was most frequently isolated. The majority of patients displayed no fever, vomiting or dehydration. The cases with clinical symptoms of fever, diarrhea, vomiting and dehydration often showed mild disease.

Objective: To investigate the antimicrobial resistance and pulsed field gel electrophoresis (PFGE) patterns of S.paratyphi A strains in Zhengzhou city isolated from sentinel hospitals in 2013-2015. Methods: According to Salmonella molecular typing and K-B drug susceptibility testing method published by international PulseNet bacterial infectious disease monitoring network and USA Clinical and Laboratory Standards Institute (CLSI2015), we analyzed drug sensitivity and PFGE molecular characteristics of 67 S.paratyphi A strains(11 strains in 2013, 7 strains in 2014, 49 strains in 2015) isolated from blood and stool samples in two sentinel hospitals of fever with rash syndrome surveillance system established in Zhengzhou city in 2013-2015. Results: The results showed 67 strains of S.paratyphi A had different levels of resistance to 13 kinds of antibiotics, 65 strains were multi-drug resistant strains (97.0%), 5 isolates were resistant to 2-3 kinds of antibiotics (7.5%), 41 isolates were resistant to 5-8 kinds of antibiotics (61.2%),11 isolates were resistant to 9-10 kinds of antibiotics(16.4%),8 isolates were resistant to 11-12 kinds of antibiotics(11.9%). 67 strains of S.paratyphi A were divided into 10 molecular patterns(PTYA1-PTYA10) by digestion with XbaⅠ restriction endonuclease and pulsed field gel electrophoresis, each pattern contains 1-48 strains with similarity ranged from 94.31%-100%. PTYA3 contained 48 strains, which was predominant band type; PTYA1, 9 contained 6 strains; PTYA 2, 4, 5, 6, 7, 8, 10 contained 1 strains among them. Conclusion The status of drug resistance of clinical isolates of S.paratyphi A in Zhengzhou city was rather serious, PFGE patterns showed diversity and dominant characteristics. The PFGE patterns of partial strains and its corresponding anti-drug spectrum have certain relevance and cluster relationship.

Objective To evaluate different detection methods in the diagnosis of severe fever with thrombocytopenia syndrome (SFTS), and find the most quick and accurate one for the identification of new bunyavirus infection. Methods Real-time PCR and ELISA-IgM were used to detect serum samples of 158 patients with acute phase of SFTS, which were collected from the special monitoring system of SFTS in Henan Province in 2014. IgM and IgG antibodies were detected by ELISA in 109 acute and convalescent paired serum specimens. The differences of the positive rates were compared between the three methods, and the influence of the collected interval time on the detection results was analyzed. Results For 158 acute phase serum samples of SFTS patients, the positive rate detected by real-time PCR (76.58%) was higher than that of ELISA-IgM (47.47%), and the difference was statistically significant (χ2=34.13, P < 0.05). For 109 cases with acute and convalescent paired serum samples, there was no significant difference in the positive rates between ELISA-IgG ( 75.23%) and real-time PCR (72.48%) detections (χ2=0.18, P>0.05). In both the acute phase and convalescent phase, the positive rate of IgM was higher than that of IgG, and the difference was statistically significant (χ2=41.68 and 6.25, P<0.05). With the extension of collected interral time, the positive rates of IgM and IgG antibodies were both increased ( Z=6.42 and 10.08, P < 0.05). Conclusion Real-time PCR is the most sensitive method for the early diagnosis of the SFTS. ELISA-IgG is suitable for the detection of SFTS at recovery period. ELISA-IgM can be used as an assistant method to guide clinical diagnosis.