Epidemiological Surveillance: Genetic Diversity of Rotavirus Group A in the Pearl River Delta, Guangdong, China in 2019

Objective This study aimed to understand the epidemic status and phylogenetic relationships of rotavirus group A(RVA)in the Pearl River Delta region of Guangdong Province,China.Methods This study included individuals aged 28 days–85 years.A total of 706 stool samples from patients with acute gastroenteritis collected between January 2019 and January 2020 were analyzed for 17 causative pathogens,including RVA,using a Gastrointestinal Pathogen Panel,followed by genotyping,virus isolation,and complete sequencing to assess the genetic diversity of RVA.Results The overall RVA infection rate was 14.59%(103/706),with an irregular epidemiological pattern.The proportion of co-infection with RVA and other pathogens was 39.81%(41/103).Acute gastroenteritis is highly prevalent in young children aged 0–1 year,and RVA is the key pathogen circulating in patients 6–10 months of age with diarrhea.G9P[8](58.25%,60/103)was found to be the predominant genotype in the RVA strains,and the 41 RVA-positive strains that were successfully sequenced belonged to three different RVA genotypes in the phylogenetic analysis.Recombination analysis showed that gene reassortment events,selection pressure,codon usage bias,gene polymorphism,and post-translational modifications(PTMs)occurred in the G9P[8]and G3P[8]strains.Conclusion This study provides molecular evidence of RVA prevalence in the Pearl River Delta region of China,further enriching the existing information on its genetics and evolutionary characteristics and suggesting the emergence of genetic diversity.Strengthening the surveillance of genotypic changes and gene reassortment in RVA strains is essential for further research and a better understanding of strain variations for further vaccine development.

Epidemiology and characteristics of identified early mpox cases in Guangdong Province,China:Implications for prevention and control

In June 2023,the 2022 global mpox(monkeypox)outbreak began to affect Guangdong Province,one of the first regions in China's Mainland to report mpox cases.By July 10,2023,93 mpox cases had been reported in Guangdong Province.This study describes the epidemiological characteristics of these patients by collecting and analyzing data on demographics,sexual behavior,medical history,travel history,clinical symptoms,and diagnostic pathways and processes.The 93 mpox cases were all men aged 20-48 years,95.70%were men who have sex with men(MSM),and 48.39%were HIV-positive.A few cases were married(to women)or living with children.The rash was present in almost all cases(98.91%),with the most common sites being the genital and perianal areas(70.33%).Intimate sexual contact was suspected to be the main route of infection,with a median incubation period of 8.5 days(IQR 5.0–11.8).The number of cases increased rapidly,and most patients had no history of international travel,suggesting sustained community transmission within the MSM population in Guangdong Province.In addition,93.55%of cases were detected by medical institutions,and more than half of these patients had two or more hospital visits before being diagnosed as an mpox case,indicating that clinicians need further training to increase their sensitivity to mpox.Targeted interventions should prioritize MSM while remaining vigilant for transmission to other populations,such as women and children.

Progressing our knowledge of enterovirus:Epidemiology,diagnosis,prevention,control,and beyond

We are thrilled to present this dedicated issue spotlighting enterovirus infections and health in Biosafety and Health.The articles presented in this issue span the broad spectrum of current research in this vital field,providing insights into the epidemiology,diagnostic procedures,and pathogenesis of enterovirus infections.Enteroviruses,a genus of RNA viruses encompassing polioviruses,coxsackieviruses,and echoviruses,play a crucial role in public health.

Cancer incidence and mortality in Guangdong province,2012

Objective： To estimate the cancer incidence and mortality in 2012 in Guangdong province by analyzing the cancer data of selected population-based cancer registries in Guangdong province in 2012. Methods： Eight of nine population-based cancer registries submitted cancer data to the Guangdong Provincial Centre for Disease Control and Prevention （Guangdong CDC）, whose data met the data quality criteria were included for analysis. The statistics of selected registries, stratified by areas, gender, age and cancer types, were used to estimate the cancer incidence and mortality in 2012 in Guangdong province according to the population data in Guangdong province. Segi＇s population and the national census population in 2000 were used for calculating the age-standardized rates （ASR）. Results： A total of 15,084,942 people, accounted for 17.47% of all population in Guangdong province, were covered in 8 selected population-based cancer registries in 2012. The percentage of cases morphologically verified （MV%） and the percentage of death certificate-only cases （DCO%） were 72.84% and 0.87%, respectively, and the mortality/incidence （M/I） ratio was 0.56. It was estimated that there were 211,300 new cancer cases and 117,300 cancer deaths. The incidence crude rate （CR）, the ASR by Chinese standard population （ASRC） and by world standard population （ASRW）, and the accumulated rate （AR） （0-74 years） were 250.20/100,000 （265.39/100,000 in males, 234.29/100,000 in females）, 207.04/100,000, 201.34/100,000 and 22.91%, respectively, in Guangdong province in 2012. The incidence CR and ASRC were 267.25/100,000 and 221.43/100,000 in urban areas, and 215.51/100,000 and 178.77/100,000 in rural areas, respectively. The death CR, ASRC, ASRW and AR （0-74 years） were 148.44/100,000 （190.95/100,000 in males, 105.06/100,000 in females）, 103.73/100,000, 102.44/100,000 and 11.68%, respectively, in Guangdong province in 2012. The death CR and ASRC were 164.57/100,000 and 105.46/100,000 in urban areas, and 124.63/100,000 and 99.97/100,000 in rural areas, respectively. Top 5 cancers were lung cancer, liver cancer, female breast cancer, colon cancer and nasopharyngeal cancers （NPC）, and top 5 death cancers were lung cancer, liver cancer, colon cancer, stomach cancer, and NPC in Guangdong province in 2012. Conclusions： Lung cancer, liver cancer, female breast cancer, colon cancer and NPC were the major economic cancer burdens and health concerns in Guangdong province in 2012. Early prevention, diagnosis and treatment of different cancers, survival quality improvement and cancer burden reduction, are important issues we faced in cancer control and prevention.

Genomic Evolution and Variation of SARS-CoV-2 in the Early Phase of COVID-19 Pandemic in Guangdong Province,China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)with unknown origin spread rapidly to 222 countries,areas or territories.To investigate the genomic evolution and variation in the early phase of COVID-19 pandemic in Guangdong,60 specimens of SARS-CoV-2 were used to perform whole genome sequencing,and genomics,amino acid variation and Spike protein structure modeling analyses.Phylogenetic analysis suggested that the early variation in the SARS-CoV-2 genome was still intra-species,with no evolution to other coronaviruses.There were one to seven nucleotide variations(SNVs)in each genome and all SNVs were distributed in various fragments of the genome.The Spike protein bound with human receptor,an amino acid salt bridge and a potential furin cleavage site were found in the SARS-CoV-2 using molecular modeling.Our study clarifed the characteristics of SARS-CoV-2 genomic evolution,variation and Spike protein structure in the early phase of local cases in Guangdong,which provided reference for generating prevention and control strategies and tracing the source of new outbreaks.

Human GSTs Polymorphisms in the Hakka Population of South China and Their Associations with Family History of Several Chronic Diseases

Objective To investigate the associations of genetic polymorphisms in GSTs genes of the Hakka population of south China with family histories of certain chronic diseases.Methods Five hundred and thirty‐nine healthy Hakka natives of Meizhou city of Guangdong province in south China were involved.The genotypes of GSTM1,GSTT1,GSTP1,GSTM3,and GSTA1 were determined using PCR and restriction fragment length polymorphism analysis.The observed polymorphisms were analyzed by Chi‐square and Hardy‐Weinberg equilibrium tests.Logistic regression analysis was used to determine the associations of the distributions of GST genotypes with family history of certain chronic diseases.Results The distributions of polymorphisms in GSTP1,GSTM3,and GSTA1 conformed to the Hardy‐Weinberg equilibrium.Compared to the Cantonese,the Hakka had a lower distribution of the GSTM3 deletion genotype （3.15% vs.11.9%）.A weak association was observed between the GSTM1 genetic polymorphism and family history of hypertension.Alcohol drinkers had a higher frequency of the null‐GSTM1 genotype,while smokers had a higher frequency of a variant GSTP1 genotype.Conclusion The results suggest that the Hakka is a special and distinctive Han Chinese ethnic group with different GSTs genetic polymorphisms.Smoking and drinking might be related to the distribution of GST genotypes.

Durable and enhanced immunity against SARS-CoV-2 elicited by manganese nanoadjuvant formulated subunit vaccine

Dear editor,Vaccines are the most efficient and effective means to prevent infectious diseases,but improving the long-term protective efficacy is still a major challenge in contemporary vaccine development.1 The waning immunity varies depending on the diversification of the pathogen and the number of booster doses.1 Strategies to overcome this warrant is using adjuvants that amplify the immune response,and drive the production of memory B and T cells or long-lived plasma cells that recognize the pathogen for durable protection.2–4 Although existing adjuvants have achieved promising results,research on generating durable protective immunity is lacking in promoting vaccine development and staying ahead of global pandemics such as coronavirus disease 2019(COVID-19).The precisely designed nanoadjuvants can enhance lymph node targeting and increase antigenpresenting cell(APCs)uptake,achieving the co-delivery of adjuvants and antigens and activating innate and adaptive immune responses.5 Previously,we reported a manganese nanoadjuvant(MnARK)and receptor-binding domain(RBD)monomer antigen formulated nanovaccine.6 MnARK transported antigens to lymph nodes,activated the STING pathway,elicited strong neutralizing abilities and increased immune memory T cell percentage against the infection of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).6 Regarding the long-term protection potential of MnARK for subunit vaccine development,we further explored the durable immune regulation abilities of MnARK to a SARS-CoV-2 RBD dimer antigen,which has been used in an approved COVID-19 subunit vaccine ZF2001 with aluminum adjuvant(alum).7,8 TEM result revealed that RBD dimer could interact with BSA on MnARK surface and epitope can be well preserved(Supplementary Fig.1a).The size and zeta potential of MnARK-RBD dimer nanovaccine was~58 nm and-14 mV,respectively(Supplementary Fig.1b,c).

Incidence and mortality of primary bone cancers in China, 2014

Objective: In this study, we aimed to estimate the updated incidence and mortality of primary bone cancers based on population-based cancer registration data in 2014, collected by the National Central Cancer Registry of China(NCCRC).Methods: In 2017, 339 registries' data were qualified based on data quality criteria set down by the NCCRC.Cases of primary bone cancers were retrieved from the national database. We estimated numbers of primary bone cancer cases and deaths in China using age-specific rates and corresponding national population stratified by area,sex, age-group(0, 1-4, 5-9, 10-14, …, 85+). Chinese standard population in 2000 and Segi's World population were applied for the calculation of age-standardized incidence and mortality rates.Results: In 2014, 24,000 primary bone cancer cases and 17,200 deaths attributable to primary bone cancers were estimated to have occurred in China. The crude incidence rate of primary bone cancers was 1.76/100,000, with agestandardized incidence rate by Chinese standard population(ASIRC) and by World standard population(ASIRW)being 1.35/100,000 and 1.32/100,000, respectively. The crude mortality rate of primary bone cancers was1.26/100,000, with age-standardized mortality rate by Chinese standard population(ASMRC) and by World standard population(ASMRW) being 0.88/100,000 and 0.86/100,000, respectively. Age-specific incidence curve was bimodally distributed with age, with the first peak occurring in the second decade of the life and the second peak in the elderly. Males had higher crude and age-standardized rates for both incidence and mortality compared with females. Both crude and age-standardized incidence rates were higher in rural areas than in urban areas, so were the crude and age-standardized mortality rates.Conclusions: This population-based study presents the most recently available estimates on primary bone cancers in China, revealing that the males are 1.34 times as much as females suffering from primary bone cancers and the adolescents in puberty and the elderly are predominantly affected groups by these cancers. High-quality cancer registration data are a prerequisite for undertaking further study for gaining insight into the causes and risk factors for primary bone cancers in China.

Molecular Typing of Brucella Suis Collected from 1960s to 2010s in China by MLVA and PFGE

Brucellosis is a bacterial anthropozoonosis usually caused by Brucella abortus, Brucella melitensis, Brucella suis and Brucella canis. Brucella suis, the causative agent of swine brucellosis, is classified into five biovars and preferentially infects different animal hostsIll. In China, brucellosis is a national notifiable communicable disease both in animals and in human. In 2009, 35 816 brucellosis cases were reported. The annual incidence was 2.7 per 100 000 population.

Numerical investigation of airborne transmission of respiratory infections on the subway platform

Underground subway platforms are among the world’s busiest public transportation systems,but the airborne transmission mechanism of respiratory infections on these platforms has been rarely studied.Here,computational fluid dynamics(CFD)modeling is used to investigate the airflow patterns and infection risks in an island platform under two common ventilation modes:Mode 1-both sides have air inlets and outlets;Mode 2-air inlets are present at the two sides and outlets are present in the middle.Under the investigated scenario,airflow structure is characterized by the ventilation jet and human thermal plumes.Their interaction with the infector’s breathing jet imposes the front passenger under the highest exposure risk by short-range airborne route,with intake fractions up to 2.57%(oral breathing)or 0.63%(nasal breathing)under Mode 1;oral breathing of the infector may impose higher risks for the front passenger compared with nasal breathing.Pathogen are efficiently diluted as they travel further,in particular to adjacent crowds.The maximum and median value of intake fractions of passengers in adjacent crowds are respectively 0.093%and 0.016%(oral breathing),and 0.073%and 0.014%(nasal breathing)under Mode 1.Compared with Mode 1,the 2nd mode minimizes the interaction of ventilation jet and breathing jet,where the maximum intake fraction is only 0.34%,and the median value in the same crowd and other crowds are reduced by 23–63%.Combining published quanta generation rate data of COVID-19 and influenza infectors,the predicted maximum and median infection risks for passengers in the same crowds are respectively 1.46%–40.23%and 0.038%–1.67%during the 3–10 min waiting period,which are more sensitive to ventilation rate and exposure time compared with return air.This study can provide practical guidance for the prevention of respiratory infections in subway platforms.

Estimation of cancer burden in Guangdong Province,China in 2009

Background:Surveying regional cancer incidence and mortality provides significant data that can assist in making health policy for local areas;however,the province- and region-based cancer burden in China is seldom reported.In this study,we estimated cancer incidence and mortality in Guangdong Province,China and presented basic information for making policies related to health resource allocation and disease control.Methods:A log-linear model was used to calculate the sex-,age-,and registry-specific ratios of incidence to mortality(l/M) based on cancer registry data from Guangzhou,Zhongshan,and Sihui between 2004 and 2008.The cancer incidences in 2009 were then estimated according to representative l/M ratios and the mortality records from eight death surveillance sites in Guangdong Province.The cancer incidences in each city were estimated by the corresponding sex- and age-specific incidences from cancer registries or death surveillance sites in each area.Finally,the total and region-based cancer incidences and mortalities for the entire population of Guangdong Province were summarized.Results:The estimated l/M ratios in Guangzhou(3.658),Zhongshan(2.153),and Sihui(1.527) were significantly different(P < 0.001),with an average l/M ratio of 2.446.Significant differences in the estimated l/M ratios were observed between distinct age groups and the three cancer registries.The estimated l/M ratio in females was significantly higher than that in males(2.864 vs.2.027,P < 0.001).It was estimated that there were 163,376 new cancer cases(99,689 males and 63,687 females) in 2009;it was further estimated that 115,049 people(75,054 males and 39,995females) died from cancer in Guangdong Province in 2009.The estimated crude and age-standardized rate of incidences(ASRI) in Guangdong Province were 231.34 and 246.87 per 100,000 males,respectively,and 156.98 and 163.57 per 100,000 females,respectively.The estimated crude and age-standardized rate of mortalities(ASRM) in Guangdong Province were 174.17 and 187.46 per 100,000 males,respectively,and 98.59 and 102.00 per 100,000 females,respectively.In comparison with the western area and the northern mountain area,higher ASRI and ASRM were recorded in the Pearl River Delta area and the eastern area in both males and females.Conclusions:Cancer imposes a heavy disease burden,and cancer patterns are unevenly distributed throughout Guangdong Province.More health resources should be allocated to cancer control,especially in the western and northern mountain areas.

Serological Study of An Imported Case of Middle East Respiratory Syndrome and His Close Contacts in China, 2015

The first imported Middle East respiratory syndrome （MERS） case in China was identified in May 2015. We determined the kinetics of antibody （IgG and IgM） and neutralizing antibodies against MERS-coronavirus （MERS-CoV） in this case before discharge. Moreover, no seroconversion was found among 53 close contacts by anti-MERS IgG antibody enzyme-linked immunosorbent assay （ELISA） of paired serum samples. These findings suggest that neither community nor nosocomial transmission of MERS-CoV occurred in China.

Key Social Determinants to Narrow the Gap between Health-adjusted Life Expectancy and Life Expectancy in Megacities

Objective Improvement in the quality of life is reflected in the narrowing of the gap between healthadjusted life expectancy(HALE)and life expectancy(LE).The effect of megacity expansion on narrowing the gap is rarely reported.This study aimed to disclose this potential relationship.Methods Annual life tables were constructed from identified death records and population counts from multiple administrative sources in Guangzhou,China,from 2010 to 2020.Joinpoint regression was used to evaluate the temporal trend.Generalized principal component analysis and multilevel models were applied to examine the county-level association between the gap and social determinants.Results Although LE and HALE in megacities are increasing steadily,their gap is widening.Socioeconomic and health services are guaranteed to narrow this gap.Increasing personal wealth,a growing number of newborns and healthy immigrants,high urbanization,and healthy aging have helped in narrowing this gap.Conclusion In megacities,parallel LE and HALE growth should be highly considered to narrow their gap.Multiple social determinants need to be integrated as a whole to formulate public health plans.

Genomic Epidemiology of Imported Cases of COVID-19 in Guangdong Province,China,October 2020–May 2021

Objective The pandemic of severe acute respiratory syndrome coronavirus 2(SARS-Co V-2) has been engendering enormous hazards to the world. We obtained the complete genome sequences of SARSCo V-2 from imported cases admitted to the Guangzhou Eighth People’s Hospital, which was appointed by the Guangdong provincial government to treat coronavirus disease 2019(COVID-19). The SARS-Co V-2 diversity was analyzed, and the mutation characteristics, time, and regional trend of variant emergence were evaluated.Methods In total, 177 throat swab samples were obtained from COVID-19 patients(from October2020 to May 2021). High-throughput sequencing technology was used to detect the viral sequences of patients infected with SARS-Co V-2. Phylogenetic and molecular evolutionary analyses were used to evaluate the mutation characteristics and the time and regional trends of variants.Results We observed that the imported cases mainly occurred after January 2021, peaking in May2021, with the highest proportion observed from cases originating from the United States. The main lineages were found in Europe, Africa, and North America, and B.1.1.7 and B.1.351 were the two major sublineages. Sublineage B.1.618 was the Asian lineage(Indian) found in this study, and B.1.1.228 was not included in the lineage list of the Pangolin web. A reasonably high homology was observed among all samples. The total frequency of mutations showed that the open reading frame 1 a(ORF1 a) protein had the highest mutation density at the nucleotide level, and the D614 G mutation in the spike protein was the commonest at the amino acid level. Most importantly, we identified some amino acid mutations in positions S, ORF7 b, and ORF9 b, and they have neither been reported on the Global Initiative of Sharing All Influenza Data nor published in Pub Med among all missense mutations.Conclusion These results suggested the diversity of lineages and sublineages and the high homology at the amino acid level among imported cases infected with SARS-Co V-2 in Guangdong Province, China.

Immunogenicity and safety of a recombinant fusion protein vaccine(V-01)against coronavirus disease 2019 in healthy adults:a randomized,double-blind,placebo-controlled,phaseⅡtrial

Background:Innovative coronavirus disease 2019(COVID-19)vaccines,with elevated global manufacturing capacity,enhanced safety and efficacy,simplified dosing regimens,and distribution that is less cold chain-dependent,are still global imperatives for tackling the ongoing pandemic.A previous phase I trial indicated that the recombinant COVID-19 vaccine(V-01),which contains a fusion protein(IFN-PADRE-RBD-Fc dimer)as its antigen,is safe and well tolerated,capable of inducing rapid and robust immune responses,and warranted further testing in additional clinical trials.Herein,we aimed to assess the immunogenicity and safety of V-01,providing rationales of appropriate dose regimen for further efficacy study.Methods:A randomized,double-blind,placebo-controlled phaseⅡclinical trial was initiated at the Gaozhou Municipal Centre for Disease Control and Prevention(Guangdong,China)in March 2021.Both younger(n=440;18–59 years of age)and older(n=440;≥60 years of age)adult participants in this trial were sequentially recruited into two distinct groups:two-dose regimen group in which participants were randomized either to follow a 10 or 25 mg of V-01 or placebo given intramuscularly 21 days apart(allocation ratio,3:3:1,n=120,120,40 for each regimen,respectively),or one-dose regimen groups in which participants were randomized either to receive a single injection of 50 mg of V-01 or placebo(allocation ratio,3:1,n=120,40,respectively).The primary immunogenicity endpoints were the geometric mean titers of neutralizing antibodies against live severe acute respiratory syndrome coronavirus 2,and specific binding antibodies to the receptor binding domain(RBD).The primary safety endpoint evaluation was the frequencies and percentages of overall adverse events(AEs)within 30 days after full immunization.Results:V-01 provoked substantial immune responses in the two-dose group,achieving encouragingly high titers of neutralizing antibody and anti-RBDimmunoglobulin,which peaked at day 35(161.9[95%confidence interval[CI]:133.3–196.7]and 149.3[95%CI:123.9–179.9]in 10 and 25 mg V-01 group of younger adults,respectively;111.6[95%CI:89.6–139.1]and 111.1[95%CI:89.2–138.4]in 10 and 25 mg V-01 group of older adults,respectively),and remained high at day 49 after a day-21 second dose;these levels significantly exceed those in convalescent serum from symptomatic COVID-19 patients(53.6,95%CI:31.3–91.7).Our preliminary data showthat V-01 is safe andwell tolerated,with reactogenicity predominantly being absent or mild in severity and only one vaccinerelated grade 3 or worse AE being observed within 30 days.The older adult participants demonstrated a more favorable safety profile compared with those in the younger adult group:with AEs percentages of 19.2%,25.8%,17.5%in older adults vs.34.2%,23.3%,26.7%in younger adults at the 10,25 mg V-01 two-dose group,and 50 mg V-01 one-dose group,respectively.Conclusions:The vaccine candidate V-01 appears to be safe and immunogenic.The preliminary findings support the advancement of the two-dose,10 mg V-01 regimen to a phaseⅢtrial for a large-scale population-based evaluation of safety and efficacy.

COVID-19-like symptoms observed in Chinese tree shrews infected with SARS-CoV-2

Thecoronavirusdisease2019(COVID-19)pandemic continues to pose a global threat to the human population. Identifying animal species susceptible to infection with the SARS-CoV-2/HCoV-19 pathogen is essential for controlling the outbreak and for testing valid prophylactics or therapeutics based on animal model studies. Here,different aged Chinese tree shrews(adult group, 1 year old;old group, 5–6 years old), which are close relatives to primates, were infected with SARS-CoV-2. X-ray, viral shedding, laboratory, and histological analyses were performed on different days postinoculation(dpi). Results showed that Chinese tree shrews could be infected by SARS-CoV-2. Lung infiltrates were visible in X-ray radiographs in most infected animals. Viral RNA was consistently detected in lung tissues from infected animals at 3,5, and 7 dpi, along with alterations in related parameters from routine blood tests and serum biochemistry, including increased levels of aspartate aminotransferase(AST) and blood urea nitrogen(BUN). Histological analysis of lung tissues from animals at 3 dpi(adult group) and 7 dpi(old group) showed thickened alveolar septa and interstitial hemorrhage. Several differences were found between the two different aged groups in regard to viral shedding peak. Our results indicate that Chinese tree shrews have the potential to be used as animal models for SARS-CoV-2 infection.

Characteristics of Settings and Etiologic Agents of Foodborne Disease Outbreaks—China,2020

Introduction:Foodborne diseases are a growing public health problem and have caused a large burden of disease in China.This study analyzed epidemiological characteristics of foodborne diseases in China in 2020 to provide a scientific basis for prevention and control measures.Methods:Data were collected from 30 of 31 provincial-level administrative divisions(PLADs)in the mainland of China,excluding Xizang(Tibet)Autonomous Region,via the National Foodborne Disease Outbreaks Surveillance System・The number and proportion of outbreaks,illnesses,hospitalizations,deaths by setting,pathogen-food category pairs and etiology were calculated.Results:In 2020,7,073 foodborne disease outbreaks were reported,resulting in 37,454 illnesses and 143 deaths.Among the identified pathogens,microbial pathogens were the most common confirmed etiology,accounting for 41.7%of illnesses.Poisonous mushrooms caused the largest proportion of outbreaks(58.0%)and deaths(57.6%).For venues where foodborne disease outbreaks occur,household had the highest number of outbreaks(4,140)and deaths(128),and catering service locations caused the largest proportion of illnesses(59.9%).Outbreaks occurring between June and September accounted for 62.8%of total outbreaks.Conclusions:Foodborne disease outbreaks mainly occurred in households・Microbial pathogens remained the top cause of outbreak-associated illnesses.Poisonous mushrooms were ranked the top cause of deaths in private homes in China.The supervision and management of food safety and health education should be strengthened to reduce the burden of foodborne diseases・Publicity should be increased to reduce the incidence of mushroom poisonings in families,and supervision and management of food should be strengthened to reduce microbial contamination.

An Imported Case and an Infected Close Contact of the Omicron Variant of SARS-CoV-2—Guangdong Province,China,December 13,2021

On November 27,2021,a 67-year-old male returning from Canada via airplane was transferred to the central isolation hotel in Shanghai.During the quarantine,his 1st,4th,7th,and 14th days of specimens returned negative for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which causes coronavirus disease 2019(COVID-19).On December 11,he completed 14 days of centralized isolation and returned to Guangzhou from Shanghai via airplane,then he was closed-loop transferred to Yuexiu District for a 7-day home isolation.On December 12,the local Community Health Service Center routinely collected his throat swab and the result returned to COVID-19 positive on December 13,2021.He was transported to the Guangzhou Eighth People’s Hospital for isolated treatment by negative pressure ambulance on the same day.The patient had two inflamed lungs according to the chest computed tomography(CT)examination,but his most recently updated condition was stable.An estimated 600 close contacts were identified and were placed in centralized isolation.On December 16,one of the close contacts,a 70-year-old female also tested positive for COVID-19.She lived on the lower floor of the same type of apartment as the imported case and spent 19 hours in the same building.

Spatial distribution and habitat suitability of Biomphalaria straminea,intermediate host of Schistosoma mansoni,in Guangdong,China

Background:Biomphalaria straminea is an invasive vector in China,posing a significant threat to public health.Understanding the factors affecting the establishment of this snail is crucial to improve our ability to manage its dispersal and potential risk of schistosomiasis transmission.This study sought to determine the spatial distribution of B.straminea in China's Mainland and whether environmental factors were divergent between places with and without B.straminea.Methods:A malacological survey of B.straminea was conducted in Guangdong Province,China.Snails were identified using anatomical keys.Water and sediment samples were taken,and their physicochemical properties were analyzed using national standard methods.Landscape and climatic variables were also collected for each site.We compared the environmental characteristics between sites with and without B.straminea using Mann-Whitney U test.We further used generalized linear mixed models to account for seasonal effects.Results:B.straminea was found at six sites,including one in Dongguan and five in Shenzhen.Probability map found a hot spot of B.straminea distribution at Shenzhen and Hong Kong.Sites occupied by B.straminea were characterized by higher median altitude,mean annual precipitation and moderate temperature.Water with snails had higher median concentrations of total nitrogen,nitrate and nitrites,ammoniacal nitrogen,calcium,zinc and manganese but lower dissolved oxygen and magnesium.Sediments with snails had higher median copper,zinc and manganese.B.straminea was associated with maximum temperature of the warmest month(pMCMC<0.001)and sediment zinc(pMCMC<0.001).Conclusions:B.straminea is distributed in Shenzhen and its surrounding areas in Guangdong,China.Sites with and without B.straminea differed in the maximum temperature of the warmest month and sediment zinc.Surveillance should be continued to monitor the dispersal of this snail in China.

Reappearance of Risk of Schistosomiasis Transmission and the Response After 27 Years of Interrupted Transmission—Guangdong Province,China,2019

Summary What is already known about this topic?No live specimens of the snail Oncomelania hupensis(O.hupensis)and indigenous infected cases of schistosomiasis japonicum have been found in Guangdong Province since 1993,but live O.hupensis was found again in 2019.This study conducted O.hupensis identification and elimination.What is added by this report?In 2019,live O.hupensis specimens were detected by routine surveillance in areas in Qujiang of Shaoguan City and Yingde of Qingyuan City,and an emergency response was launched immediately.