Objective: To analyze the epidemiological characteristics and trends of other infectious diarrhea among children under 18 years old in Guangzhou City from 2014 to 2020, and to explore the correlation between climatic factors and the incidence of the disease, so as to provide reference for the early prevention of infectious diseases. Methods: The data of cases of other infectious diarrhea and meteorological data of children under 18 years old in Guangzhou City from 2014 to 2020 were collected through the Chinese Infectious Disease Reporting System and the Guangzhou Meteorological Bureau. The correlation between meteorological factors and the incidence of other infectious diarrhea was analyzed using negative binomial regression. Results: A total of 104 566 cases of other infectious diarrhea among children under 18 years old were reported in Guangzhou City from 2014 to 2020, with a male to female ratio of 1.48∶1. The incidence rate was the highest in 2017 (980.83 per 100 000) and the lowest in 2020 (388.22 per 100 000). The peak of incidence occurred from October to March of the following year. Children under 5 years old accounted for 87.95% of all cases. The number of cases of other infectious diarrhea was negatively correlated with the temperature of the previous 6 days ( IRR = -0.07 ), and positively correlated with the temperature difference on the day of onset ( IRR =0.02) (both P <0.05). It was also positively correlated with the wind speed of the previous 7 days ( IRR=0.07, P <0.05), but there was no statistically significant correlation with the relative humidity on the day of onset ( IRR=-0.00, P >0.05). Conclusions Low temperature, large temperature difference, and high wind speed can increase the risk of other infectious diarrhea. It is necessary to strengthen the prediction and early warning in conjunction with meteorological changes, and warn kindergartens and schools to enhance preventive measures against the clustering of other infectious diarrhea cases.

Objective:The purpose of this study was to analyze the epidemiological characteristics of hand, foot, and mouth disease (HFMD) among individuals aged 6 years and above in Guangzhou from 2010 to 2023, with the intention that a scientific basis be provided for effective prevention and control measures in older age groups.Methods:Data on HFMD incidence among individuals aged 6 years and above in Guangzhou from 2010 to 2023 were collected and analyzed. Descriptive epidemiological methods were used to analyze the distributions and pathogen components of HFMD cases in Guangzhou residents aged 6 years and above. Spatial autocorrelation analysis and Getis-Ord Gi* analysis were conducted to identify the spatial clustering patterns of HFMD at the street town level. Results:From 2010 to 2023, the gender ratio of HFMD cases in persons aged 6 and above was 1.49∶1 in Guangzhou. The average annual incidence rate of HFMD among individuals aged 6 years and above in Guangzhou was 25.75 per 100 000. Furthermore, the reported incidence rate indicated an increased tendency. The annual incidence showed a bimodal distribution, with the main peak occurring from May to July and the secondary peak from September to October. HFMD incidence rates vary by townships, with hotspots clustered in urban and urban-rural regions. The dominant pathogen shifts from year to year. Enterovirus 71 (EV71) was the prevalent strain in 2010, followed by other enteroviruses and Coxsackievirus (CV)-A16 from 2011 to 2016. Since 2017, CV-A6 has steadily become the major pathogen.Conclusions:The incidence of HFMD cases among individuals aged 6 years and above in Guangzhou increased generally from 2010 to 2023, with hotspots localized in urban and urban-rural areas. The pathogen composition altered dramatically, with the proportion of EV71 dropping overall, while CV-A6 eventually became the dominating strain. Therefore, it is imperative to focus on the prevention and control of HFMD in this age group, especially by strengthening measures in areas with high prevalence.

Mass vaccination represents a highly effective strategy for accelerating disease control while simultaneously reducing incidence and mortality rates. By developing comprehensive plans and standards for mass vaccination, it is feasible to optimize resource allocation and swiftly enhance vaccination coverage, thereby preventing, controlling, or interrupting outbreaks or epidemics of specific infectious diseases. To standardize the mass vaccination process and establish a population immunity barrier in an orderly, efficient, and safe manner, a panel of experts was convened to develop the Recommendations on Mass Vaccination. These recommendations are grounded in the requirements of relevant policies and regulations in China, as well as the insights gained from the mass vaccination campaign for COVID-19 vaccines conducted in the country. The recommendations outline the system requirements pertaining to initiation conditions, departmental coordination, responsibilities, mobilization, operational specifications, and responses to vaccine reactions, among other aspects of mass vaccination implementation, so as to serve as a reference for future mass vaccination initiatives and the formulation of related policies.

Objective:To analyze the immunization status of routine vaccines for children aged 0-7 years old with special health status in Tianhe District, Guangzhou City, from 2023 to 2024.Methods:From April 2023 to March 2024, 42 vaccination units in Tianhe District, Guangzhou, were organized to collect data on diseases and vaccination history of children with special health status. Vaccination rates were calculated, and multivariate logistic regression models were used to explore the impact of special health status on vaccination rates.Results:A total of 1 976 children aged 0-7 years old with special health status were included, with an average of (1.26±0.58) diseases per participant. The average number of vaccine doses administered for routine immunizations was (14.29±4.27), and the full vaccination coverage was 72.76%. The vaccination rate of 10 doses in the immunization program vaccine was less than 90.00%. The timely rate of the first dose of hepatitis B vaccine (HepB1) was 74.14%, and that of the first dose of measles vaccine (MCV1) was 63.93%. Compared with children with infectious diseases, those with neonatal diseases were more likely to miss the third dose of poliomyelitis vaccine (PV3), MCV1 and the second dose of Group A meningococcal polysaccharide vaccine (MPSV-A2). Those with neuromuscular system diseases were more likely to miss PV3, MPSV-A2 and the first dose of Japanese encephalitis vaccine, live (JE-L1). Those with congenital heart disease were more likely to miss PV3, the third dose of diphtheria tetanus-acellular pertussis vaccine (DTaP3), MCV1, MPSV-A2, and JE-L1. Those with hematological disorders were more likely to miss PV3, MCV1, MPSV-A2, and JE-L1. Those with genetic diseases were more likely to miss MPSV-A2. Those with comorbidities were more likely to miss MCV1 and MPSV-A2. Those with neonatal diseases, neuromuscular system diseases, congenital heart disease, hematopoietic system diseases, genetic diseases, or comorbidities had difficulties in completing the full vaccination process.Conclusion:Children with special health conditions have lower rates of routine immunization and timely vaccination. More measures are needed to improve vaccination rates.

Objective:The purpose of this study was to analyze the epidemiological characteristics of hand, foot, and mouth disease (HFMD) among individuals aged 6 years and above in Guangzhou from 2010 to 2023, with the intention that a scientific basis be provided for effective prevention and control measures in older age groups.Methods:Data on HFMD incidence among individuals aged 6 years and above in Guangzhou from 2010 to 2023 were collected and analyzed. Descriptive epidemiological methods were used to analyze the distributions and pathogen components of HFMD cases in Guangzhou residents aged 6 years and above. Spatial autocorrelation analysis and Getis-Ord Gi* analysis were conducted to identify the spatial clustering patterns of HFMD at the street town level. Results:From 2010 to 2023, the gender ratio of HFMD cases in persons aged 6 and above was 1.49∶1 in Guangzhou. The average annual incidence rate of HFMD among individuals aged 6 years and above in Guangzhou was 25.75 per 100 000. Furthermore, the reported incidence rate indicated an increased tendency. The annual incidence showed a bimodal distribution, with the main peak occurring from May to July and the secondary peak from September to October. HFMD incidence rates vary by townships, with hotspots clustered in urban and urban-rural regions. The dominant pathogen shifts from year to year. Enterovirus 71 (EV71) was the prevalent strain in 2010, followed by other enteroviruses and Coxsackievirus (CV)-A16 from 2011 to 2016. Since 2017, CV-A6 has steadily become the major pathogen.Conclusions:The incidence of HFMD cases among individuals aged 6 years and above in Guangzhou increased generally from 2010 to 2023, with hotspots localized in urban and urban-rural areas. The pathogen composition altered dramatically, with the proportion of EV71 dropping overall, while CV-A6 eventually became the dominating strain. Therefore, it is imperative to focus on the prevention and control of HFMD in this age group, especially by strengthening measures in areas with high prevalence.

Mass vaccination represents a highly effective strategy for accelerating disease control while simultaneously reducing incidence and mortality rates. By developing comprehensive plans and standards for mass vaccination, it is feasible to optimize resource allocation and swiftly enhance vaccination coverage, thereby preventing, controlling, or interrupting outbreaks or epidemics of specific infectious diseases. To standardize the mass vaccination process and establish a population immunity barrier in an orderly, efficient, and safe manner, a panel of experts was convened to develop the Recommendations on Mass Vaccination. These recommendations are grounded in the requirements of relevant policies and regulations in China, as well as the insights gained from the mass vaccination campaign for COVID-19 vaccines conducted in the country. The recommendations outline the system requirements pertaining to initiation conditions, departmental coordination, responsibilities, mobilization, operational specifications, and responses to vaccine reactions, among other aspects of mass vaccination implementation, so as to serve as a reference for future mass vaccination initiatives and the formulation of related policies.

Objective:To analyze the immunization status of routine vaccines for children aged 0-7 years old with special health status in Tianhe District, Guangzhou City, from 2023 to 2024.Methods:From April 2023 to March 2024, 42 vaccination units in Tianhe District, Guangzhou, were organized to collect data on diseases and vaccination history of children with special health status. Vaccination rates were calculated, and multivariate logistic regression models were used to explore the impact of special health status on vaccination rates.Results:A total of 1 976 children aged 0-7 years old with special health status were included, with an average of (1.26±0.58) diseases per participant. The average number of vaccine doses administered for routine immunizations was (14.29±4.27), and the full vaccination coverage was 72.76%. The vaccination rate of 10 doses in the immunization program vaccine was less than 90.00%. The timely rate of the first dose of hepatitis B vaccine (HepB1) was 74.14%, and that of the first dose of measles vaccine (MCV1) was 63.93%. Compared with children with infectious diseases, those with neonatal diseases were more likely to miss the third dose of poliomyelitis vaccine (PV3), MCV1 and the second dose of Group A meningococcal polysaccharide vaccine (MPSV-A2). Those with neuromuscular system diseases were more likely to miss PV3, MPSV-A2 and the first dose of Japanese encephalitis vaccine, live (JE-L1). Those with congenital heart disease were more likely to miss PV3, the third dose of diphtheria tetanus-acellular pertussis vaccine (DTaP3), MCV1, MPSV-A2, and JE-L1. Those with hematological disorders were more likely to miss PV3, MCV1, MPSV-A2, and JE-L1. Those with genetic diseases were more likely to miss MPSV-A2. Those with comorbidities were more likely to miss MCV1 and MPSV-A2. Those with neonatal diseases, neuromuscular system diseases, congenital heart disease, hematopoietic system diseases, genetic diseases, or comorbidities had difficulties in completing the full vaccination process.Conclusion:Children with special health conditions have lower rates of routine immunization and timely vaccination. More measures are needed to improve vaccination rates.

To monitor and analyze the molecular variation of the H3N2 influenza virus in Guangzhou during the COVID-19 pandemic, respiratory samples of influenza-like cases from influenza monitoring sentinel hospitals were collected from influenza monitoring sentinel hospitals for virus isolation and whole genome sequencing. The results showed that during COVID-19, there was only one peak of H3N2 influenza in the second quarter of 2022 in Guangzhou (the positive rate was 52.23%), and the epidemic intensity and duration were both higher than those in 2019. The HA gene and NA gene of the epidemic strain in Guangzhou in 2022 belonged to the 3C.2a1b. 2a. 1a. 1 branch, which had a good antigenic site matching with the vaccine strain (A/Cambodia/e0826360/2020) from 2021 to 2022 and had no antigen drift. In 2022 strains, the variation of antigen determinant mainly occurred in the I48T of C region, while no variation occurred in the A, B, D, and E regions. The binding site of the HA protein receptor was consistent with the vaccine strain (A/Cambodia/e0826360/2020). Most of the strains in 2022 carried 13 glycosylation sites on the HA protein, but an outbreak of strains caused a loss of glycosylation sites at 24-NST. In conclusion, the strains that caused the epidemic of H3N2 influenza in Guangzhou in 2022 were not evolved or transmitted from the local strains in 2019 during the COVID-19 pandemic.

Objective:To establish a rapid pipeline for whole genome sequencing of Chikungunya virus (CHIKV) by combining imbricated multiplex-PCR amplification and Illumina high-throughput sequencing platform.Methods:The primary reference sequences of CHIKV were downloaded from the National Center for Biotechnology Information (NCBI) database, covering all genotypes of CHIKV. After multiple alignments using the Mafft software and phylogenetic analysis, the 20 CHIKV references were selected for primer design. The Primal Scheme tool and Geneious Prime software were used to design, evaluate and optimize the primer panel. Finally, seven CHIKV-positive samples were involved in the validation of the primer panel.Results:All the amplicons of the designed panel were generated successfully. The consensuses generated from the mapping results could cover 100.00% of the coding region of the CHIKV genome when the Ct-value of the sample was less than 33, as the percentage would decrease to 99.38% when the Ct-value reached 35. The mapping percentage could be increased by 5.70%-25.43% when using the stepwise correction mapping strategy.Conclusion:The multiplex-PCR amplification method for CHIKV whole genome sequencing is relatively simple and convenient, which only requires two tubes of PCR amplification and performs well on CHIKV-positive clinical samples with different concentration levels of virus.

To monitor and analyze the molecular variation of the H3N2 influenza virus in Guangzhou during the COVID-19 pandemic, respiratory samples of influenza-like cases from influenza monitoring sentinel hospitals were collected from influenza monitoring sentinel hospitals for virus isolation and whole genome sequencing. The results showed that during COVID-19, there was only one peak of H3N2 influenza in the second quarter of 2022 in Guangzhou (the positive rate was 52.23%), and the epidemic intensity and duration were both higher than those in 2019. The HA gene and NA gene of the epidemic strain in Guangzhou in 2022 belonged to the 3C.2a1b. 2a. 1a. 1 branch, which had a good antigenic site matching with the vaccine strain (A/Cambodia/e0826360/2020) from 2021 to 2022 and had no antigen drift. In 2022 strains, the variation of antigen determinant mainly occurred in the I48T of C region, while no variation occurred in the A, B, D, and E regions. The binding site of the HA protein receptor was consistent with the vaccine strain (A/Cambodia/e0826360/2020). Most of the strains in 2022 carried 13 glycosylation sites on the HA protein, but an outbreak of strains caused a loss of glycosylation sites at 24-NST. In conclusion, the strains that caused the epidemic of H3N2 influenza in Guangzhou in 2022 were not evolved or transmitted from the local strains in 2019 during the COVID-19 pandemic.