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Objective@#To systematically review the mortality burden study of influenza in mainland China.@*Method@#"influenza", "flu", "H1N1", "pandemic", "mortality", "death", "fatality", "burden", "China" and "Chinese" were used as keywords, and a systematic literature search was conducted to identify articles in three English databases (PubMed, Web of Science and Embase) and three Chinese database (CNKI, WanFang and VIP) during 1990-2018 (excluding Hong Kong, Macao and Taiwan). The language of literature was restricted to Chinese and English. The inclusion criteria were human-oriented researches with method based on population, and research indexes included mortality and excess mortality. The exclusion criteria were non-primary research materials, predictive research and research on the burden of avian influenza related deaths. A total of 17 literatures were included, and the basic information to descriptive characteristics, methodology of modeling and the corresponding results were extracted.@*Results@#All the 17 studies adopted indirect statistical models, with 14 of which adopted the regression model, and all the research index was excess mortality. All causes (16 studies), respiratory and circulatory diseases (14 studies) and pneumonia and influenza (10 studies) were the main causes of death associated with influenza. Influenza associated mortality burden in the elderly was higher, with the lowest excess mortality rates of all causes, respiratory and circulatory diseases, pneumonia and influenza being 49.57, 30.80 and 0.69 per 100 000 people, and the highest rates being 228.16, 170.20 and 30.35 per 100 000 people, respectively. In the non-elderly, the corresponding lowest rates were -0.27, -0.08 and 0.04 per 100 000 people respectively, and the highest rates were 3.63, 2.6 and 0.91 per 100 000 people, respectively. The influenza-related excess mortality was higher in the north, with a minimum of 7.8 per 100 000 and a maximum of 18.0 per 100 000, and slightly lower in the south, with a minimum of 6.11 per 100 000 and a maximum of 18.7 per 100 000. There were also differences in deaths caused by different influenza virus subtypes, with influenza A(H3N2) and influenza B virus possibly posing a heavier mortality burden.@*Conclusions@#Studies on influenza mortality burden is mainly based on indirect model and urban level in China. The mortality burden of influenza in the elderly, the northern and subtype A(H3N2) and B were more severe.
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Objective@#Using three models too estimate excess mortality associated with influenza of Shanxi Province during 2013-2017.@*Methods@#Mortality data and influenza surveillance data of 11 cities of Shanxi Province from the 2013-2014 through 2016-2017 were used to estimate influenza-associated all cause deaths, circulatory and respiratory deaths and respiratory deaths. Three models were used: (i) Serfling regression, (ii)Poisson regression, (iii)General line model.@*Results@#The total reported death cases of all cause were 157 733, annual death cases of all cause were 39 433, among these cases, male cases 93 831 (59.50%), cases above 65 years old 123 931 (78.57%). Annual influenza-associated excess mortality, for all causes, circulatory and respiratory deaths, respiratory deaths were 8.62 deaths per 100 000, 6.33 deaths per 100 000 and 0.68 deaths per 100 000 estimated by Serfling model, respectively; and 21.30 deaths per 100 000, 16.89 deaths per 100 000 and 2.14 deaths per 100 000 estimated by General line model, respectively; and 21.76 deaths per 100 000, 17.03 deaths per 100 000 and 2.05 deaths per 100 000, estimated by Poisson model, respectively. Influenza-related excess mortality was higher in people over 75 years old; influenza-associated excess mortalityfor all causes, circulatory and respiratory deaths, respiratory deaths were 259.67 deaths per 100 000, 229.90 deaths per 100 000 and 32.63 deaths per 100 000, estimated by GLM model, respectively; and 269.49 deaths per 100 000, 233.69 deaths per 100 000 and 31.27 deaths per 100 000, estimated by Poisson model,respectively.@*Conclusion@#Excess mortality associated with influenza mainly caused by A (H3N2), Influenza caused the most associated death amongold people.
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Objective@#We planned to evaluate the effectiveness of moving epidemic method (MEM) in calculating influenza epidemic threshold of 7 climatic zones in China mainland.@*Methods@#The positive rate of influenza virus was obtained from the National Influenza Surveillance Network System from 2010/2011 to 2017/2018. We divided the 31 provinces into 7 climatic zones according to previous literatures and applied MEM to calculate the influenza epidemic threshold of 2018/2019 influenza season for these climatic zones. Sensitivity, specificity, positive predictive value and negative predictive value were calculated to evaluate the effectiveness of MEM.@*Results@#Pre-epidemic threshold (the positive rate of influenza virus) varied from 9.66% (temperate zone) to 16.36% (subtropical zone) for 2018/2019 influenza season. The gap between pre-epidemic and post-epidemic thresholds was less than 5% except for plateau zone. The sensitivity was 86.16% (95CI:66.81%-98.23%), the specificity was 94.92% (95CI: 91.13%-98.41%), the positive predictive value was 89.87% (95%CI: 84.39%-94.38%), the negative predictive value was 92.96% (95%CI: 84.46%-99.17%).@*Conclusion@#Overall, moving epidemic Method performs well in calculating influenza epidemic threshold in China, much better than the previous study.
ABSTRACT
Health care workers have higher risk of influenza infection because of their occupational exposure to infected patients. Infection of the health care workers may not only result in the increasing risk of the nosocomial infection and family transmission, but also disrupt the health services due to absence from work. Health care workers were recommended as a priority group of influenza vaccinationin more than 40 countries and regions in the world. In recent years, domestic surveys show that the influenza vaccine coverage among health care workers was low. This paper outlines the current status and related policies of influenza vaccination among health care workers in China and global. Additionally, we analyzed and discussed the proper immunization strategy of influenza vaccine for medical staff in China.
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The annual deaths associated with influenza is estimated to be between 290 000 and 650 000,which caused substantial burden to the society.Children have the highest incidence of influenza among all age groups,which can cause overloaded medical visits and a significant increase of hospitalization risk.The severe economic burden includes not only the direct medical costs due to outpatients and hospitalization,but also the indirect burden of school absence of children and work absence of their family members.Annual vaccination is the best measure to prevent influenza,however,influenza vaccination coverage among children in China is very low,and influenza vaccination has not yet been included in the National Immunization Program.Now,the disease burden of influenza and the vaccine usage in children in China were reviewed,and in order to provide evidence for influenza control and prevention.
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Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and its complications.Currently,China has licensed trivalent (IIV3) and quadrivalent inactivated influenza vaccine (IIV4),including split-virus influenza vaccine and subunit vaccine.In most parts of China,influenza vaccine is a category Ⅱ vaccine,which means influenza vaccination is voluntary,and recipients need to pay for it.To strengthen the technical guidance for prevention and control of influenza and the operational research on influenza vaccination in China,the National Immunization Advisory Committee (NIAC),Influenza Vaccine Technical Working Group (TWG),updated the 2014 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2018-2019)",based on most recent existing scientific evidences.The main updates include:epidemiology and disease burden of influenza,types of influenza vaccines,northern hemisphere influenza vaccination composition for the 2018-2019 season,and,IIV3 and IIV4 vaccines' major immune responses,durability of immunity,immunogenicity,vaccine efficacy,effectiveness,safety,cost-effectiveness and cost-benefit.The recommendations include:Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications.No preferential recommendation is made for any influenza vaccine product for persons who can accept ≥ 1 licensed,recommended,and appropriate products.To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups,the recommendations prioritize seasonal influenza vaccination for children aged 6-60 months,adults ≥60 years of age,persons with specific chronic diseases,healthcare workers,the family members and caregivers of infants ＜6 months of age,and pregnant women or women who plan to pregnant during the influenza season.Children aged 6 months to 8 years old require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection.If they were vaccinated in previous influenza season,1 dose is recommended.People ≥ 9 years old require 1 dose of influenza vaccine.It is recommended that people receive their influenza vaccination by the end of October.Influenza vaccination should be offered as soon as the vaccination is available.Influenza vaccination should continue to be available for those unable to be vaccinated before the end of October during the whole season.Influenza vaccine is also recommended for use in pregnant women during any trimester.These guidelines are intended for CDC members who are working on influenza control and prevention,PoVs members,healthcare workers from the departments of pediatrics,internal medicine,and infectious diseases,and members of materuity and child care institutions at all levels.
ABSTRACT
Influenza can be prevented through annual appropriate vaccination against the virus concerned.In China,influenza vaccine is categorized as "Class Ⅱ " infectious diseases which the cost is paid out of the user's pockets.The annual coverage of influenza vaccination had been 2％-3％.The main reasons for the low coverage would include the following factors:lacking awareness on both the disease and vaccine,poor accessibility of vaccination service,and the cost of vaccination.To reduce the health and economic burden associated with influenza,comprehensive policies should be improved,targeting the coverage of seasonal influenza vaccination.These items would include:① Different financing reimbursement schemes and mechanisms to improve the aspiration on vaccination and on the vaccine coverage in high-risk groups,as young children,elderly,people with underlying medical conditions;② to ameliorate equality of vaccination services;③ to improve knowledge of the health care workers (HCWs) and the public on influenza and related vaccines;④ to improve clinical and preventive medical practice and vaccination among HCWs through revising clinical guidelines,pathway and consensus of experts;⑤ to provide more convenient,accessible and normative vaccination service system;⑥ to strengthen research and development as well as marketing on novel influenza vaccines;⑦ to revise items regarding the contraindication for influenza vaccine on pregnancy women,stated in the Chinese Pharmacopoeia.
ABSTRACT
In China,the control and prevention programs on any disease has always been based on comprehensive strategies.Take influenza as an example,related contents would include:strengthening the surveillance,recommendation and promotion of vaccination,rational use of antiviral drugs,conducting outbreak investigation and control,and publicizing individual protective measures,etc.In terms of the response to challenges,specific proposals would include:adjustment of case reports,optimization of surveillance systems,reinforcement of vaccination recommendation by health care workers,improvement of access to vaccination,development of rapid diagnostic reagents,and rational use of antiviral drugs,etc.
ABSTRACT
Five influenza pandemics had occurred during the past century (1918 "Spanish flu",1957 "Asian flu",1968 "Hong Kong flu",1977 "Russian flu" and 2009 H1N1 Pandemic),accounting for hundreds of millions of people infected and tens of millions dead.China was influenced by all the five pandemics,and three of them (1957 "Asian flu",1968 "Hong Kong flu" and 1977 "Russian flu") were originated from China.The pandemics triggered the establishment of public health agencies and influenza surveillance capacities.In addition,more resources were allocated to influenza-related research,prevention and control.As a leader in the field of influenza,China should further strengthen its pandemic preparedness and response to contribute to global health.
ABSTRACT
Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and complications from infection. Currently, China has licensed trivalent inactivated influenza vaccine (IIV3) and quadrivalent inactivated influenza vaccine (IIV4), including split-virus influenza vaccine and subunit vaccine. Except for a few major cities, influenza vaccine is a category Ⅱ vaccine, which means influenza vaccination is voluntary, and recipients must pay for it. To strengthen the technical guidance for prevention and control of influenza and operational research on influenza vaccination in China, the National Immunization Advisory Committee (NIAC) Influenza Vaccine Technical Working Group (TWG), updated the 2014 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2018-2019)" . The main updates in this version include: epidemiology, disease burden, types of influenza vaccines, northern hemisphere influenza vaccination composition for the 2018-2019 season, IIV3 and IIV4 immune response, durability of immunity, immunogenicity, vaccine efficacy, effectiveness, safety, cost-effectiveness and cost-benefit. The influenza vaccine TWG provided the recommendations for influenza vaccination for the 2018-2019 influenza season based on existing scientific evidence. The recommendations described in this report include the following: Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications. No preferential recommendation is made for one influenza vaccine product over another for persons for whom more than one licensed, recommended, and appropriate product is available. To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups, the recommendations prioritize seasonal influenza vaccination for children aged 6-59 months, adults ≥60 years of age, persons with specific chronic diseases, healthcare workers, the family members and caregivers of infants <6 months of age, and pregnant women or women who plan to become pregnant during the influenza season. Children aged 6 months through 8 years require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection. If they were vaccinated in 2017-2018 influenza season or a prior season, 1 dose is recommended. People more than 8 years old require 1 dose of influenza vaccine. It is recommended that people receive their influenza vaccination by the end of October. Influenza vaccination should be offered as soon as the vaccination is available. For the people unable to be vaccinated before the end of October, influenza vaccination will continue to be offered for the whole season. Influenza vaccine is also recommended for use in pregnant women during any trimester. These guidelines are intended for use by staff members of the Centers for Disease Control and Prevention at all levels who work on influenza control and prevention, PoVs staff members, healthcare workers from the departments of pediatrics, internal medicine, and infectious diseases, and staff members of maternity and child care institutions at all levels.
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Objective@#To understand characteristics of demographic, seasonal and spatial distribution of H5N1 cases in major countries of Asia (Indonesia, Cambodia, Vietnam, China) and Africa (Egypt).@*Methods@#Through searching public data resource and published papers, we collected cases information in five countries from May 1st, 1997 to November 6th, 2017, including general characteristics, diagnosis, onset and exposure history, etc. Different characteristics of survived and death cases in different countries were described and χ2 test was used to compare the differences among death cases and odds ratio (OR) and 95%CI value was used to compare death risk in different countries.@*Results@#A total of 856 cases were reported in five countries with Egypt had the most cases (44.3%). The highest number of cases were reported in 2015 (18.3%). 53% cases were reported from January to March, and 96.1% of cases had the history of poultry exposure. 64.2% (43 cases) cases in China had live poultry market exposure, but the sick/dead poultry exposure was the major exposure for cases in other four countries. 452 death cases were reported in five countries, and the fatality rate was 52.8%. With Egypt as the reference group, the highest death risk was seen in Indonesia (OR (95%CI): 11.52 (7.46-17.77)), followed by Cambodia (OR (95%CI): 4.27(2.37-7.69)) and China (OR (95%CI): 2.87 (1.73-4.74)). The age distribution of death cases among 5 countries was statistically significant, and the highest fatality rate was in 15-54 years group in Egypt (83.6%, 102 cases), while in Cambodia the highest fatality rate was in 0-14 years group (76.9%, 30 cases). The highest number of deaths were reported in 2006, and 48.3% were reported from January to March. There was difference in exposure routes among 5 countries (χ2=43.85, P=0.001), 63.2% (24 cases) of the death cases in China had live poultry market exposure. 92.9% (79 cases), 83.3% (40 cases) and 100.0% (38 cases) death cases in Indonesia, Vietnam and Camodia had sick/dead poultry exposure, respectively;and 81.6% (31 cases) of the death cases in Egypt had backyard poultry exposure.@*Conclusion@#The geographical distribution, seasonal age, gender, exposure matter and outcome of H5N1 cases in five countries were different.
ABSTRACT
Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and its complications.Currently,China has licensed trivalent (IIV3) and quadrivalent inactivated influenza vaccine (IIV4),including split-virus influenza vaccine and subunit vaccine.In most parts of China,influenza vaccine is a category Ⅱ vaccine,which means influenza vaccination is voluntary,and recipients need to pay for it.To strengthen the technical guidance for prevention and control of influenza and the operational research on influenza vaccination in China,the National Immunization Advisory Committee (NIAC),Influenza Vaccine Technical Working Group (TWG),updated the 2014 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2018-2019)",based on most recent existing scientific evidences.The main updates include:epidemiology and disease burden of influenza,types of influenza vaccines,northern hemisphere influenza vaccination composition for the 2018-2019 season,and,IIV3 and IIV4 vaccines' major immune responses,durability of immunity,immunogenicity,vaccine efficacy,effectiveness,safety,cost-effectiveness and cost-benefit.The recommendations include:Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications.No preferential recommendation is made for any influenza vaccine product for persons who can accept ≥ 1 licensed,recommended,and appropriate products.To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups,the recommendations prioritize seasonal influenza vaccination for children aged 6-60 months,adults ≥60 years of age,persons with specific chronic diseases,healthcare workers,the family members and caregivers of infants ＜6 months of age,and pregnant women or women who plan to pregnant during the influenza season.Children aged 6 months to 8 years old require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection.If they were vaccinated in previous influenza season,1 dose is recommended.People ≥ 9 years old require 1 dose of influenza vaccine.It is recommended that people receive their influenza vaccination by the end of October.Influenza vaccination should be offered as soon as the vaccination is available.Influenza vaccination should continue to be available for those unable to be vaccinated before the end of October during the whole season.Influenza vaccine is also recommended for use in pregnant women during any trimester.These guidelines are intended for CDC members who are working on influenza control and prevention,PoVs members,healthcare workers from the departments of pediatrics,internal medicine,and infectious diseases,and members of materuity and child care institutions at all levels.
ABSTRACT
Influenza can be prevented through annual appropriate vaccination against the virus concerned.In China,influenza vaccine is categorized as "Class Ⅱ " infectious diseases which the cost is paid out of the user's pockets.The annual coverage of influenza vaccination had been 2％-3％.The main reasons for the low coverage would include the following factors:lacking awareness on both the disease and vaccine,poor accessibility of vaccination service,and the cost of vaccination.To reduce the health and economic burden associated with influenza,comprehensive policies should be improved,targeting the coverage of seasonal influenza vaccination.These items would include:① Different financing reimbursement schemes and mechanisms to improve the aspiration on vaccination and on the vaccine coverage in high-risk groups,as young children,elderly,people with underlying medical conditions;② to ameliorate equality of vaccination services;③ to improve knowledge of the health care workers (HCWs) and the public on influenza and related vaccines;④ to improve clinical and preventive medical practice and vaccination among HCWs through revising clinical guidelines,pathway and consensus of experts;⑤ to provide more convenient,accessible and normative vaccination service system;⑥ to strengthen research and development as well as marketing on novel influenza vaccines;⑦ to revise items regarding the contraindication for influenza vaccine on pregnancy women,stated in the Chinese Pharmacopoeia.
ABSTRACT
In China,the control and prevention programs on any disease has always been based on comprehensive strategies.Take influenza as an example,related contents would include:strengthening the surveillance,recommendation and promotion of vaccination,rational use of antiviral drugs,conducting outbreak investigation and control,and publicizing individual protective measures,etc.In terms of the response to challenges,specific proposals would include:adjustment of case reports,optimization of surveillance systems,reinforcement of vaccination recommendation by health care workers,improvement of access to vaccination,development of rapid diagnostic reagents,and rational use of antiviral drugs,etc.
ABSTRACT
Five influenza pandemics had occurred during the past century (1918 "Spanish flu",1957 "Asian flu",1968 "Hong Kong flu",1977 "Russian flu" and 2009 H1N1 Pandemic),accounting for hundreds of millions of people infected and tens of millions dead.China was influenced by all the five pandemics,and three of them (1957 "Asian flu",1968 "Hong Kong flu" and 1977 "Russian flu") were originated from China.The pandemics triggered the establishment of public health agencies and influenza surveillance capacities.In addition,more resources were allocated to influenza-related research,prevention and control.As a leader in the field of influenza,China should further strengthen its pandemic preparedness and response to contribute to global health.
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<p><b>OBJECTIVE</b>To investigate clinical and epidemiological characteristics of hospitalized severe acute respiratory illnesses (SARI) patients under 15 years old registered by sentinel hospitals at 10 cities and risk factors analysis of severe illness.</p><p><b>METHODS</b>The objects of this study were 2 937 SARI patients under 15 years old registered by sentinel surveillance in internal wards, pediatrics wards and intensive care units (ICU) of 10 sentinel hospitals in 10 cities during the period from December 2009 to June 2014. We also collected case report form (CRF) of them and their throat swabs for influenza testing. The inclusion criteria was hospitalized patients who were admitted by surveillance departments, registered by SARI surveillance system, under 15 years old, meeting SARI case definition and with complete CRF. Rank-sum test was used to compare the difference of age, the duration including from onset to admission, hospital stay and from onset to discharging/death between mild illness and severe illness. Chi-square test was used to compare the difference of demographic characteristics, influenza psoitive rate, vaccination rate of influenza, chronic medical conditions and clinical characteristics between mild illness and severe illness. Logistic regression was used to analysis risk factors associated with severe illness by two stratifications from SARI surveillance protocol (< 2 years old and ≥ 2 years old).</p><p><b>RESULTS</b>Among 2 937 SARI patients under 15 years old, 97.7% (2 872/2 937) was mild illnesses, and 2.3% (65/2 937) was severe illnesses. 78.8% (2 315/2 937) was under 5 years old. The median ages of severe illness and mild illness were 0.4 and 2.0 years old (U = -6.23, P < 0.001). The proportions of severe illness and mild illness with at least one chronic medical condition were 32.3% (21/65) and 8.4% (240/2 872) (χ² = 45.03, P < 0.001). The positive rate of influenza virus was 6.5% (190/2 937), which was 6.5% (186/2 858) for mild illness and 6.2% (4/65) for severe illness (χ² = 0.08, P = 0.961). The proportion of seasonal influenza vaccination was 1.5% (42/2 853), which was 1.5% (42/2 788) for mild illness and higher than that for severe illness (0) (χ² = 6.09, P = 0.048). For under 2 years old patients, age < 11 months and with at least one chronic medical condition were risk factors for severe SARI illness, and the risk for SARI patients who was 12-23 months and without medical condition was 14.71 (5.35-40.44) and 5.61 (2.96-10.63). For ≥ 2 years old patients, age, with at least one chronic medical condition and seasonal influenza vaccination history have no association with severe illness, OR (95% CI) was 0.92 (0.80-1.05), 0.67 (0.09-5.05) and 0.85 (0.31-2.35), respectively.</p><p><b>CONCLUSION</b>Most of SARI patients registered by 10 urban sentinel hospitals were patients under 5 years old. Age < 11 months and with at least chronic medical conditions were possible risk factors of severe illness of SARI patients.</p>
Subject(s)
Adolescent , Child , Child, Preschool , Humans , Infant , China , Chronic Disease , Cities , Hospitalization , Hospitals , Influenza, Human , Orthomyxoviridae , Respiratory Tract Diseases , Risk Factors , Sentinel Surveillance , VaccinationABSTRACT
<p><b>OBJECTIVE</b>To identify clinical characteristics of hospitalized laboratory-confirmed influenza cases of children under 15 years old, and their risk factors of influenza infection.</p><p><b>METHODS</b>Analyzing the reports of hospitalized laboratory-confirmed influenza cases of children under 15 years old who were detected by the sentinel surveillance systems in 10 provinces from December 2009 to June 2014. Such data as their demographic, medical history, clinical symptoms and signs, treatment and outcome were collected using questionnaires, with their clinical characteristics and their risk factors of influenza infection described.</p><p><b>RESULTS</b>Of the 2 937 severe acute respiratory infection inpatients, 190 (6.5%) were laboratory-confirmed influenza cases. 123 (64.7%) of such confirmed cases were male, and 139 (73.2%) were children under 5 years old, with age median of 3.0 years (IQR: 1.0-5.0 years). 20 (10.5%) of them had at least one chronic medical condition, mostly chronic cardiovascular disease (3.2%), immunosuppressive disease (3.2%), and cancer/tumor (2.6%). Most common clinical symptoms of the cases were fever (92.6%) and cough (88.8%), of which abnormal pulmonary auscultation (51.1%) and abnormal chest X-ray performance (36.1%) were the most common clinical signs. 29 cases (15.8%) had complications, of which pneumonia (15.3%) was most common. 16 cases (8.6%) used antiviral drugs, and 4 cases (2.2%) were admitted into ICU. Risk factor analysis suggested that age < 6 months (OR = 0.406, 95% CI: 0.203-0.815) was a protective factor against influenza infection; and age 5-9 years old (OR = 2.535, 95% CI: 1.059-6.066) was a risk factor for influenza infection.</p><p><b>CONCLUSION</b>Hospitalized laboratory-confirmed influenza cases were found mostly in children under 5 years old. Risk exposure for influenza infection varied among age groups.</p>
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Male , Acute Disease , Antiviral Agents , China , Epidemiology , Cough , Fever , Hospitalization , Influenza A Virus, H1N1 Subtype , Influenza, Human , Epidemiology , Pathology , Inpatients , Laboratories , Protective Factors , Risk Assessment , Risk Factors , Sentinel Surveillance , Surveys and QuestionnairesABSTRACT
<p><b>OBJECTIVE</b>To identity the clinical characteristics and severe case risk factors for the adult inpatient cases confirmed of influenza monitored by the sentinel surveillance system for severe acute respiratory infection (SARI) inpatient cases in ten provinces in China.</p><p><b>METHODS</b>Epidemiology and clinical information surveys were conducted for adult cases (≥ 15 year old) consistent with SARI case definition, who were monitored by SARI sentinel hospitals in ten cities in China from December 2009 to June 2014, with their respiratory tract specimens collected for influenza RNA detection. Adult SARI cases were classified into influenza inpatient group and outpatient group by the detection outcomes, analyzing their demographic information, clinical and epidemiology characteristics respectively, in addition to risk factors for severe inpatient cases.</p><p><b>RESULTS</b>3 071 adult SARI cases were recruited from ten hospitals, including 240 (7.8%) cases of laboratory-confirmed influenza, most of them being A (H1N1) pdm2009 and A (H3N2) sub-types. Age M of the included influenza cases was 63 year old, 47.1% of them being ≥ 65 seniors. 144 (60.0%) cases of the influenza inpatients suffered from at least one chronic underlying condition, and the proportion of emphysema (7.9%) was higher than non-influenza inpatient cases (3.8%), being statistically significant (χ(2) = 3.963, P = 0.047). 19.4% of the women of childbearing age infected of influenza were in pregnancy, and only 1.1% of the 240 influenza cases had been vaccinated against influenza. The proportion of sore throat and dyspnea found among influenza inpatients was higher than inpatients without influenza. 17.4% of the influenza cases were accepted into ICU for treatment, with no statistical significance with non-influenza inpatient cases (P = 0.160). 23.1% of the influenza inpatients received an antiviral drug therapy, a figure higher than the non-influenza inpatient cases (4.8%) (P < 0.001). 41.5% of the inpatients developed complications, with the proportion of viral pneumonia significantly higher than the non-influenza inpatient cases (P < 0.001). Asthma (RR = 15.200, 95% CI: 1.157-199.633), immunosuppressive diseases (RR = 5.250, 95% CI: 1.255-21.960), pregnancy (RR = 21.000, 95% CI: 1.734-254.275), time interval from onset to admission less 7 days (RR = 1.673, 95% CI: 1.071-2.614) were identified as risk factors of severely-ill influenza cases.</p><p><b>CONCLUSION</b>It was found that adult influenza inpatients were mostly ≥ 65 year old seniors. The influenza vaccination rate among the influenza cases was very low, and antivirus drugs were used less than necessary. In this regard, influenza vaccination was recommended for high risk groups of pregnant women, seniors and chronic disease patients on annual basis, while influenza inpatients were advised to use antiviral drugs as early as possible.</p>
Subject(s)
Adult , Aged , Female , Humans , Pregnancy , Antiviral Agents , China , Epidemiology , Hospitalization , Influenza A Virus, H1N1 Subtype , Influenza A Virus, H3N2 Subtype , Influenza, Human , Epidemiology , Inpatients , Outpatients , Pneumonia, Viral , Respiratory Tract Infections , Risk Factors , Sentinel Surveillance , VaccinationABSTRACT
<p><b>OBJECTIVE</b>To estimate the hospitalization rate of severe acute respiratory infection (SARI) cases attributable to influenza in Jingzhou city, Hubei province from 2010 to 2012.</p><p><b>METHODS</b>SARI surveillance was conducted at four hospitals in Jingzhou city, Hubei province from 2010 to 2012. Inpatients meeting the SARI case definition and with informed consent were enrolled to collect their demographic information, clinical features, treatment, and disease outcomes, with their respiratory tract specimens collected for PCR test of influenza virus.</p><p><b>RESULTS</b>From April, 2010 to September, 2012, 19 679 SARI cases enrolled were residents of Jingzhou, and nasopharyngeal swab was collected from 18 412 (93.6%) cases of them to test influenza virus and 13.3% were positive for influenza. During the three consecutive 2010-2012 flu seasons, laboratory-confirmed influenza was associated with 102 per 100 000, 132 per 100 000 and 244 per 100 000, respectively. As for the hospitalization rate attributable to specific type/subtype of influenza virus, 48 per 100 000, 30 per 100 000 and 24 per 100 000 were attributable to A (H3N2), A (H1N1) pdm2009, and influenza B, respectively in 2010-2011 season; 42 per 100 000 [A (H3N2)] and 90 per 100 000 (influenza B) in 2011-2012 season; 90 per 100 000 [A (H3N2)] and one per 100 000 [influenza B] from April, 2010 to September, 2012. SARI hospitalization caused by influenza A or B occurred both mainly among children younger than five years old, with the peak in children aged 0.5 year old.</p><p><b>CONCLUSION</b>Influenza could cause a substantial number of hospitalizations and different viral type/subtype result in different hospitalizations over influenza seasons in Jingzhou city, Hubei province. Children less than five years old should be prioritized for influenza vaccination in China.</p>
Subject(s)
Child , Child, Preschool , Humans , Infant , China , Epidemiology , Demography , Hospitalization , Hospitals , Influenza A Virus, H1N1 Subtype , Influenza A Virus, H3N2 Subtype , Influenza, Human , Epidemiology , Inpatients , Laboratories , Orthomyxoviridae , Polymerase Chain Reaction , Respiratory Tract Infections , Seasons , VaccinationABSTRACT
<p><b>OBJECTIVE</b>To explore a sampling method which could reflect iodine deficiency disorders (IDD) status at provincial level and discover risk areas with non-iodized salt problem.</p><p><b>METHOD</b>Baseline data of Iodized salt from Gansu and Fujian provinces were analyzed with Monte Carlo method both at county and prefecture levels respectively. True positive rate and false positive rate were also calculated.</p><p><b>RESULTS</b>With data from 7 - 8 villages or 4 - 5 townships counties at risk could be discovered. The true positive rate was around 80% and false positive rate was around 20%. At prefecture level, when randomly selecting and checking 3 counties, the samples would satisfy the discovery of all the risk areas with non-iodized salt problem.</p><p><b>CONCLUSIONS</b>We suggested that the sampling method of iodized salt investigation in national IDD surveillance as follows: to randomly choose 3 counties at each prefecture, 4 townships at each county, 2 villages at each township and 10 salt samples by household survey. The coverage rate of iodized salt in a province could be calculated by post-weighted method with population number.</p>