BackgroundInfectious diarrhea remains a significant public health challenge, with climatic factors potentially playing a crucial role in its epidemiological spread. However, the precise mechanisms through which the El Niño-Southern Oscillation (ENSO) influences diarrheal morbidity are still not fully understood.MethodsWe collected monthly other infectious diarrhea (OID) incidence and climatic data across the 31 provincial administrative divisions of mainland China (2005–2019). Wavelet analysis was employed to examine the periodicity of OID and the phase relationships between ENSO, climate factors and OID. Generalized additive models (GAM) and Peter and Clark Momentary Conditional Independence (PCMCI) algorithm were used to quantify exposure-response relationship and establish causal pathways in China.ResultsFrom 2005 to 2019, a total of 13,620,167 OID cases were reported in 31 provincial regions of China, with the highest incidence of OID concentrated in the southern and eastern regions of China. Wavelet analysis identified a significant periodicity between ENSO cycles and diarrhea incidence patterns, demonstrating that La Niña events (characterized by low ENSO index) were associated with subsequent increases in incidence with a 6-month lag. The exposure-response relationship showed an inverted J-shaped curve in North and East China, while a nearly linear relationship was observed in Northeast, Central, Southwest and Northwest China. PCMCI analysis elucidated that precipitation is an indirect link between ENSO and OID.ConclusionOur study suggests that a low ENSO index (La Niña) may drive the incidence of OID in China. The findings provide a scientific basis for predicting and warning of OID based on ENSO.

Objective To estimate the socio-economic burden caused by various types of hand-foot-mouth disease(HFMD)cases in Guangdong province from 2015 to 2023.Methods On the basis of the previous studies of disease economic burden and the data of HFMD reported in Guangdong from 2015 to 2023,the economic burdens of common cases(including outpatients and inpatients),severe cases,and death cases of HFMD were estimated.The per capita productivity loss caused by premature death of HFMD in different age groups was calculated by the human capital method.Results From 2015 to 2023,a total of 2 727 381 cases of HFMD were reported in Guangdong province,with 99.96%classified as common cases,932 severe cases,and 33 death cases.The annual economic loss attributable to HFMD in Guangdong province during this period remained stable at 357 million-523 million CNY,except for a notable decrease between 2020 and 2022,when it was estimated at 76 million-370 million CNY.The economic burden of common cases accounted for 99.38%.The economic burden of severe cases accounted for 0.59%,showing a fluctuating downward trend from 5 million CNY in 2015 to 0.756 3 million CNY in 2023.The economic burden associated with death cases accounted for 1.03%,exhibiting a declining trend from 6 million CNY in 2015 to no death in 2022-2023,with premature death losses constituting 98.41%-98.66%of total death losses.Conclusions The socio-economic burden caused by HFMD in Guangdong province has been generally stable from 2015 to 2023,apart from a decline in 2020-2022.The burden was mainly attributable to common cases,and the disease burden of severe and death cases decreased with fluctuations.It is recommended that we should closely monitor changes in the composition of the economic burden of HFMD and adjust prevention and control strategies accordingly.

BackgroundChikungunya fever (CF), an arthropod-borne disease caused by Chikungunya virus (CHIKV), is a serious public health threat globally. In July 2025, an outbreak occurred in Foshan City, Guangdong Province, China. A large number of these cases involved cross-city movements, which complicated containment efforts and provided a unique opportunity to study transmission patterns and key epidemiological parameters.MethodsWe obtained information on 400 confirmed cases of CF with cross-city exposure histories reported across Guangdong Province in southern China by 21 August 2025. Demographic, clinical, and mobility data were mainly obtained from the National Notifiable Infectious Disease Reporting System and supplemented by epidemiological investigations. The incubation period was estimated using a parametric accelerated failure time model, with log-normal, gamma, Weibull, and Erlang distributions used to fit the model. Subgroup analysis was performed based on mobility patterns and exposure windows.Principal findingsSignificant demographic differences were observed compared with local Foshan cases: cross-city cases had higher proportions of males (58.3%), individuals within the age groups of 15-24, 25-34, and 35-44,and individuals with occupations of general staff/workers, business/service workers, and students. Fever (86.4%), arthralgia (79.3%), and rash (61.2%) were the most common symptoms. Mobility analysis revealed that Foshan and Guangzhou were the major sources of infection, with cases spreading mainly to cities within the Pearl River Delta and provinces such as Guangxi (43.3%) and Hunan (15.4%). The median incubation period was estimated to be 5.4 days (95% CI 5.0-5.7), with 2.5th and 97.5th percentiles of 2.5 days and 11.4 days, respectively.ConclusionsThis study underscores the central role of population mobility in the spread of CHIKV and highlights distinct epidemiological characteristics of cross-city cases. The estimated median incubation period of 5.4 days provides important evidence for surveillance and response strategies during chikungunya outbreaks. Notably, students and migrant workers accounted for a higher proportion of cross-city cases, suggesting that highly mobile populations may contribute to inter-regional transmission. These findings highlight the importance of strengthened surveillance and coordination across regions for the prevention and control of future outbreaks in Guangdong and other high-risk areas in China.

Background: In 2024, mainland China witnessed a significant upsurge in Hand, Foot, and Mouth Disease (HFMD) cases. Coxsackievirus A16 (CVA16) is one of the primary causative agents of HFMD. Long-term monitoring of theCVA16 infection rate and genotype changes is crucial for the prevention and control of HFMD. Methods: A total of 40,673 clinical specimens were collected from suspected HFMD cases in Guangdong province from 2018 to 2024, including rectal swabs (n = 27,954), throat swabs (n = 6791), stool (n = 5923), cerebrospinal fluid (n = 3), and herpes fluid (n = 2). A total of 24,410 samples were detected as EV-positive and further typed by RT-PCR. A total of 872 CVA16-positive samples were isolated and further sequenced to obtain the full-length VP1 sequence. Phylogenetic analysis was performed based on viral protein 1 gene (VP1). Results: In the first 25 weeks of 2024, reported cases of HFMD were 1.36 times higher than the mean rates of 2023. In 2024, CVA16 predominated at 75.42%, contrasting with the past etiological pattern in which the CVA6 was predominant with the detection rate ranging from 32.85 to 77.61% from 2019 to 2023. Phylogenetic analysis based on the VP1 gene revealed that the B1a and B1b subtypes co-circulated in Guangdong from 2018 to 2022. The B1c outbreak clade, detected in Guangdong in 2023, constituted 68.24% of the 148 strains of CVA16 collected in 2024, suggesting a subtype shift in the CVA16 virus. There were three specific amino acid variations (P3S, I235V, and T240A) in the VP1 sequence of B1c. Conclusions: The new emergence of the CVA16 B1c outbreak clade in Guangdong during 2023–2024 highlights the necessity for the enhanced surveillance of the virus evolution epidemiological dynamic in this region. Furthermore, it is imperative to closely monitor the etiological pattern changes in Hand, Foot, and Mouth Disease (HFMD) in other regions as well. Such vigilance will be instrumental in guiding future vaccination strategies for HFMD.

BackgroundThis study aims to evaluate the health economics of hand-foot-mouth disease enterovirus 71 (EV71) vaccination for the population of appropriate age in Guangdong Province.MethodsA SEIR model was constructed, and a group of differential equations was established. The incidence data of HFMD in Guangdong from January to June 2017 were used to fit the model and the basic reproduction value (R0) of this disease was simulated. Then, the incidence of HFMD under different vaccination coverage rate (0, 40, 70, and 90%) was simulated in four scenarios. Cost-effectiveness analysis was used to evaluate the health economics.ResultsThe self-funded voluntary EV71 vaccination strategy implemented in Guangdong Province has effectively reduced the disease economic burden of EV71-type HFMD, and the disease economic burden saved during the peak seasonal segment of HFMD in 2017 was $1,080,000. Meanwhile, Scenario 2, 3, and 4 would each result in a cumulative reduction of 6,525, 9,556, and 10,989 confirmed cases, respectively, with net monetary benefits of approximately $6.55 million, $9.59 million, and $11.2 million. The study results show that the current vaccine pricing is not cost-effectiveness, while the vaccine price is lower than $13.15, EV71 vaccination in Guangdong Province has a cost-effectiveness advantage.ConclusionVaccination can reduce the incidence of HFMD caused by EV71, which helps to improve the status of HFMD and decreases the disease burden.

BACKGROUND:During the coronavirus disease 2019 (COVID-19) pandemic, the implementation of public health intervention measures have reshaped the transmission patterns of other infectious diseases. We aimed to analyze the epidemiological characteristics of dengue in Guangdong Province, China, and to investigate the temporal shifts in dengue epidemic in Guangdong Province during the COVID-19 pandemic. METHODS:Based on the data of dengue reported cases, meteorological factors, and mosquito vector density in Guangdong Province from 2012 to 2022, wavelet analysis was applied to investigate the relationship between the dengue incidence in Southeast Asian (SEA) countries and the local dengue incidence in Guangdong Province. We constructed the dengue importation risk index to assess the monthly risk of dengue importation. Based on the counterfactual framework, we constructed the Bayesian structural time series (BSTS) model to capture the epidemic trends of dengue. RESULTS:Wavelet analysis showed that the local dengue incidence in Guangdong Province was in phase correlation with the dengue incidence of the prior month in relative SEA countries. The dengue importation risk index showed an increasing trend from 2012 to 2019, then decreased to a low level during the COVID-19 pandemic. From 2020 to 2022, the average annual number of reported imported cases and local cases of dengue in Guangdong Province were 26 and 2, respectively, with a decrease of 95.62% and 99.94% compared to the average during 2017-2019 (594 imported cases and 3,118 local cases). According to BSTS model estimates, 6557 local dengue cases may have been reduced in Guangdong Province from 2020 to 2022, with a relative reduction of 99.91% (95%CI: 98.85-99.99%). CONCLUSION:The incidence of dengue in Guangdong notably declined from 2020 to 2022, which may be related to the co-benefits of COVID-19 intervention measures and the intensified interventions against dengue during that period. Furthermore, our findings further supported that dengue is not currently endemic in Guangdong.

Generating fine-scale risk maps for mosquito-borne diseases vectors is an essential tool for guiding spatially targeted vector control interventions in urban settings, given the limited public health resources. This study aimed to generate fine-scale risk maps for dengue vectors using routine vector surveillance data collected at the township scale. We integrated monthly township-specific Breteau Index (BI) data from Guangzhou city (2019 to 2020) with covariates extracted from remote sensing imagery and other geospatial datasets to develop an original random forest (RF) model for predicting hotspot areas (BI ≥ 5). We implemented three data resampling techniques (undersampling, oversampling, and hybrid sampling) to improve the model’s performance and evaluate it using the ROC-AUC, Recall, Specificity, and G-means metrics. Finally, we generated a downscaled risk maps for BI hotspot areas at a 1000 m grid scale by applying the optimal model to fine-scale input data. Our findings indicate the following: (1) data resampling techniques significantly improved the prediction accuracy of the original RF model, demonstrating robust spatial downscaling capabilities for fine-scale grids; (2) the spatial distribution of BI hotspot areas within townships exhibits significant heterogeneity. The fine-scale risk mapping approach overcomes the limitations of previous coarse-scale risk maps and provides critical evidence for policymakers to better understand the distribution of BI hotspot areas, facilitating pixel-level spatially targeted vector control interventions in intra-urban areas.

BACKGROUND: Noroviruses are a predominant cause of acute gastroenteritis (AGE) outbreaks globally, many outbreaks are associated with waterborne transmission. However, waterborne AGE outbreaks caused by the GII.9[P7] strain are relatively rare. METHODS: In April 2024, an AGE outbreak occurred among high school students on an educational excursion in Guangdong, China. Feces or anal swabs from clinical cases and asymptomatic canteen staffs, water samples from septic tank and tap water, along with food samples were collected for pathogen detection by real-time RT-PCR, and positive samples were subsequently characterized through gene sequencing analysis. RESULTS: From 12 April to 14 April 2024, a total of 84 individuals met the case definitions. The cases occurred continuously throughout the excursion without a distinct epidemic peak and the number of cases decreased significantly after the students left on April 13. Norovirus GII was detected in 12 symptomatic cases (12/24) and an asymptomatic food handler (co-infected with rotavirus A,1/7) and all water samples (7/7). The norovirus strain was identified as GII.9[P7] based on phylogenetic analysis, with 100% nucleotide sequence identity among the clinical cases and water samples, implying that the causative agent of the outbreak originates from contaminated drinking water. CONCLUSIONS: This study identified GII.9[P7] norovirus as the causative agent of this outbreak. This was the first reported waterborne outbreak of GII.9[P7] norovirus in China. Our study highlights the necessity of an integrated environmental and clinical case surveillance system for prevention and control of norovirus-associated gastroenteritis outbreak.

Hand, foot and mouth disease (HFMD) remains a major public health challenge in China, exhibiting distinct seasonal patterns. This study integrates meteorological, behavioural and social determinants to elucidate the transmission dynamics of HFMD in Guangzhou. Utilizing surveillance data from 2012 to 2022, we employed regression analysis and developed a mechanistic transmission model incorporating absolute humidity (AH), the Baidu search index (BDI) as a proxy for health-seeking behaviour and holiday effects. The model, calibrated via Markov chain Monte Carlo methods, explained 91.4% of the case variance and estimated a mean time-varying reproduction number of 2.29. Our findings demonstrate that AH and BDI act as significant nonlinear drivers of transmission, while holidays reduced incidence by an average of 21.3%. The implementation of non-pharmaceutical interventions during the COVID-19 pandemic was associated with a substantial reduction in HFMD incidence, with cases declining by 88.1% in 2020, 36.6% in 2021 and 72.2% in 2022. This integrative modelling framework effectively captures the multifactorial drivers of HFMD seasonality and provides a robust tool for forecasting outbreaks and informing targeted public health interventions.

The evidence regarding the effectiveness of Lanzhou Lamb Rotavirus Vaccine (LLR) and RotaTeq (RV5) against gastroenteritis (RVGE) caused by emerging genotypes in Chinese children remains limited. We conducted a test-negative case–control study using gastroenteritis surveillance data from four cities (2020–2023) in Guangdong Province, China. Children aged 2 months to 5 years hospitalized with acute gastroenteritis were enrolled. Cases were rotavirus-positive; controls were rotavirus-negative. Vaccine effectiveness (VE) was estimated using multivariable logistic regressions. Among 2650 children, 218 (8.2

Here, we report on a case of human infection with the H3N8 avian influenza virus. The patient had multiple myeloma and died of severe infection. Genome analysis showed multiple gene mutations and reassortments without mammalian-adaptive mutations. This suggests that avian influenza (A/H3N8) virus infection could be lethal for immunocompromised persons.

Predicting the specific magnitude and the temporal peak of the epidemic of individual local outbreaks is critical for infectious disease control. Previous studies have indicated that significant differences in spatial transmission and epidemic magnitude of dengue were influenced by multiple factors, such as mosquito population density, climatic conditions, and population movement patterns. However, there is a lack of studies that combine the above factors to explain their complex nonlinear relationships in dengue transmission and generate accurate predictions. Therefore, to study the complex spatial diffusion of dengue, this research combined the above factors and developed a network model for spatiotemporal transmission prediction of dengue fever using metapopulation networks based on human mobility. For improving the prediction accuracy of the epidemic model, the ensemble adjusted Kalman filter (EAKF), a data assimilation algorithm, was used to iteratively assimilate the observed case data and adjust the model and parameters. Our study demonstrated that the metapopulation network-EAKF system provided accurate predictions for city-level dengue transmission trajectories in retrospective forecasts of 12 cities in Guangdong province, China. Specifically, the system accurately predicts local dengue outbreak magnitude and the temporal peak of the epidemic up to 10 wk in advance. In addition, the system predicted the peak time, peak intensity, and total number of dengue cases more accurately than isolated city-specific forecasts. The general metapopulation assimilation framework presented in our study provides a methodological foundation for establishing an accurate system with finer temporal and spatial resolution for retrospectively forecasting the magnitude and temporal peak of dengue fever outbreaks. These forecasts based on the proposed method can be interoperated to better support intervention decisions and inform the public of potential risks of disease transmission.

Objective: To explore the impact of health management measures for entry personnel (entry management measures) against COVID-19 on the epidemiological characteristics of imported Dengue fever in Guangdong Province from 2020 to 2022. Methods: Data of imported Dengue fever from January 1, 2016 to August 31, 2022, mosquito density surveillance from 2016 to 2021, and international airline passengers and Dengue fever annual reported cases from 2011 to 2021 in Guangdong were collected. Comparative analysis was conducted to explore changes in the epidemic characteristics of imported Dengue fever before the implementation of entry management measures (from January 1, 2016 to March 20, 2020) and after the implementation (from March 21, 2020 to August 31, 2022). Results: From March 21, 2020, to August 31, 2022, a total of 52 cases of imported Dengue fever cases were reported, with an imported risk intensity of 0.12, which were lower than those before implementation of entry management measures (1 828, 5.29). No significant differences were found in the characteristics of imported cases before and after implementation of entry management measures, including seasonality, sex, age, career, and imported countries (all P>0.05). 59.62% (31/52) of cases were found at the centralized isolation sites and 38.46% (20/52) at the entry ports. However, before implementation of entry management measures, 95.08% (1 738/1 828) of cases were found in hospitals. Among 51 cases who had provided entry dates, 82.35% (42/51) and 98.04% (50/51) of cases were found within seven days and fourteen days after entry, slightly higher than before implementation [(72.69%(362/498) and 97.59% (486/498)]. There was significant difference between the monthly mean values of Aedes mosquito larval density (Bretto index) from 2020 to 2021 and those from 2016 to 2019 (Z=2.83, P=0.005). There is a strong positive correlation between the annual international airline passengers volume in Guangdong from 2011 to 2021 and the annual imported Dengue fever cases (r=0.94, P<0.001), and a positive correlation also existed between the international passenger volume and the annual indigenous Dengue fever cases (r=0.72, P=0.013). Conclusions: In Guangdong, the entry management measures of centralized isolation for fourteen days after entry from abroad had been implemented, and most imported Dengue fever cases were found within fourteen days after entry. The risk of local transmission caused by imported cases has reduced significantly.

Dengue remains an important public health issue in South China. In this study, we aim to quantify the effect of climatic factors on dengue in nine cities of the Pearl River Delta (PRD) in South China. Monthly dengue cases, climatic factors, socio-economic, geographical, and mosquito density data in nine cities of the PRD from 2008 to 2019 were collected. A generalized additive model (GAM) was applied to investigate the exposure–response relationship between climatic factors (temperature and precipitation) and dengue incidence in each city. A spatio-temporal conditional autoregressive model (ST-CAR) with a Bayesian framework was employed to estimate the effect of temperature and precipitation on dengue and to explore the temporal trend of the dengue risk by adjusting the socioeconomic and geographical factors. There was a positive non-linear association between the temperature and dengue incidence in the nine cities in south China, while the approximate linear negative relationship between precipitation and dengue incidence was found in most of the cities. The ST-CAR model analysis showed the risk of dengue transmission increased by 101.0

Purpose: This study aims to identify common COVID-19 symptoms and asymptomatic infection rates during the epidemic in China. We also introduce the concepts of "Time-point asymptomatic rate" and "Period asymptomatic rate". Object and Methods: A questionnaire survey was conducted online from December 2022 to January 5, 2023, collecting demographic characteristics, laboratory results, clinical symptoms, lifestyle and vaccination history. Statistical methods were used to analyze symptom characteristics, associated factors, and patterns during an 8-day observation period. Numerical variables were described by median M (Q1-Q3) or mean and standard deviation ((x) over bar +/- s). Categorical variables are described by frequency (N), ratio (%) or rate (%). The influencing factors were studied by Wilcoxon or Kruskal-Willis H rank sum test or logistic regression analysis, and the trend of symptom incidence by Spearman rank correlation. P value being <= 0.05 was statistically significant. Results: Out of 536 participants, 493 (91.98%) were infected, with 3 asymptomatic cases and 490 symptomatic cases within 8 days. The time-point asymptomatic rate increased from 0.61% on day 1 to 15.42% on day 8. Fever, cough, and fatigue were the main symptoms, with additional symptoms such as vomiting, diarrhea, and hyposmia reported. Symptom durations varied, with cough and expectoration lasting longer and vomiting and diarrhea lasting shorter. Several symptoms showed a downward trend over time. Conclusion: Our online survey highlighted that most COVID-19 patients experienced symptoms, and the time-point asymptomatic rate showed a dynamic change among the infected population. Onset patterns and demographic factors influence symptom occurrence and duration. These findings have implications for clinical practitioners and decision-makers in public health measures and strategies.

The SARS-CoV-2 Delta variant has spread rapidly worldwide. To provide data on its virological profile, we here report the first local transmission of Delta in mainland China. All 167 infections could be traced back to the first index case. Daily sequential PCR testing of quarantined individuals indicated that the viral loads of Delta infections, when they first become PCR-positive, were on average ~1000 times greater compared to lineage A/B infections during the first epidemic wave in China in early 2020, suggesting potentially faster viral replication and greater infectiousness of Delta during early infection. The estimated transmission bottleneck size of the Delta variant was generally narrow, with 1-3 virions in 29 donor-recipient transmission pairs. However, the transmission of minor iSNVs resulted in at least 3 of the 34 substitutions that were identified in the outbreak, highlighting the contribution of intra-host variants to population-level viral diversity during rapid spread.

What is already known about this topic? The Omicron variant has been listed as a variant of concern, but the characteristics still remain unclear. What is added by this report? The vaccinated proportion of 65 imported coronavirus disease 2019 cases that were infected with Omicron variant in this study was 89.23%, which was higher than Delta cases. Most imported cases infected with Omicron were tested positive using polymerase chain reaction after entering Guangdong within 3 days, a shorter period than Delta. What are the implications for public health practice? Under this observation, the international travelers infected with Omicron variant were detected positive earlier after entry than those infected with Delta variant. Breakthrough infections occurred in most Omicron cases in this study, but vaccination was still effective to reduce the incidence of severe illness. Omicron surveillance should be strengthened.

Chikungunya fever, caused by Chikungunya virus (CHIKV), is an Aedes mosquito-borne disease present worldwide, and millions of CHIKV infections have been reported. Treatment for CHIKV includes supportive care and anti-inflammatory medications, but there are currently no antiviral treatments or vaccines. Nonstructural protein 2 (nsP2) of CHIKV is the most important functional protein mediating virus replication and amplification, making it an ideal antiviral target for CHIKV. In this study, we determined the CHIKV nsP2 Epitope Rich Region, expressed recombinant nsP2 protein, and isolated 5 nsP2-specific nanobodies (Nb-A2, Nb-A9, Nb-D7, Nb-D12 and Nb-E12) from a phage display library comprising variable domains of Camellidae heavy chain-only antibodies (VHH). We subsequently established a stable Nbs-expressing HEK293T cell line to explore antiviral function. The results showed that Nb-A9 inhibited CHIKV replication at the early stage of CHIKV infection in HEK293T cells, and protected cells against CHIKV-induced cytopathic effect (CPE). This is possibly the first report of an Nbs-based strategy against CHIKV nsP2, Nb-A9 has great potential for developing a novel antiviral drug to treat CHIKV infection. The acquisition of antibodies has laid a foundation for further research on the function of CHIKV nsP2 and the development of therapeutic drugs.

Background: The Delta variant of SARS-CoV-2 had become predominant globally by November 2021. Aim: We evaluated transmission dynamics and epidemiological characteristics of the Delta variant in an outbreak in southern China. Methods: Data on confirmed COVID-19 cases and their close contacts were retrospectively collected from the outbreak that occurred in Guangdong, China in May and June 2021. Key epidemiological parameters, temporal trend of viral loads and secondary attack rates were estimated. We also evaluated the association of vaccination with viral load and transmission. Results: We identified 167 patients infected with the Delta variant in the Guangdong outbreak. Mean estimates of latent and incubation period were 3.9 days and 5.8 days, respectively. Relatively higher viral load was observed in infections with Delta than in infections with wild-type SARS-CoV-2. Secondary attack rate among close contacts of cases with Delta was 1.4%, and 73.1% (95% credible interval (CrI): 32.9-91.4) of the transmissions occurred before onset. Index cases without vaccination (adjusted odds ratio (aOR): 2.84; 95% CI: 1.19-8.45) or with an incomplete vaccination series (aOR: 6.02; 95% CI: 2.45-18.16) were more likely to transmit infection to their contacts than those who had received the complete primary vaccination series. Discussion: Patients infected with the Delta variant had more rapid symptom onset compared with the wild type. The time varying serial interval should be accounted for in estimation of reproduction numbers. The higher viral load and higher risk of pre-symptomatic transmission indicated the challenges in control of infections with the Delta variant.

Objective To explore the seasonality, epidemiological characteristics and dynamic changes of different subtypes/lineages of influenza viruses in Guangdong Province and provide evidences for precise prevention and control of influenza in Guangdong. Methods Data on weekly influenza pathogen surveillance from the week 36of 2014 to the week 35 of 2020 were collected in Guangdong. The moving epidemic method (MEM) was used to determine annual epidemic period, and characteristic of seasonality were analyzed. The epidemiologic characteristics and dynamic change of different subtypes/lineages of influenza viruses were compared and analyzed with χ2 test. Results Influenza mainly occurred in winter, spring and summer in Guangdong. The incidence peaks mainly occurred in summer before and during 2016–2017 and in winter during and after 2017–2018. Based on data of the epidemic seasons from 2014–2015 to 2018–2019, the positive rate was lowest in age group 0–2 years, but increased with age and reached the peak in age group 7–18 years, then decreased. The distribution of the virus subtypes/lineages varied in different age groups, the proportion of influenza A virus was higher than influenza B virus. Influenza A (H1N1) pdm09 virus and influenza B virus (Yamagata lineage) were mainly detected in winter, influenza A (H3N2) virus in summer, and influenza B virus (Victoria lineage) in spring. Compared with results during before and during 2016–2017, the proportions of infections in age groups 7–18 years and 19–59 years increased, while the proportions of infections in other age groups decreased, and influenza A (H1N1) pdm09 virus and influenza B virus (Yamagata lineage) were mainly detected in winter, influenza A(H3N2) virus in spring, but influenza B virus (Victoria lineage) still in spring during and after 2017–2018. Conclusion From 2017–2018 to now, the annual incidence peak of influenza all occurred in winter. Different subtypes/lineages of influenza viruses had specific epidemiological characteristics and trends. It is necessary to continue to strengthen influenza pathogen surveillance for the precise evaluation of incidence trend and control of influenza.