Objective To analyze the epidemiological characteristics of an outbreak caused by human brucellosis in a farm in Yantai City,to explore the causes and transmission routes,and to provide evidence for prevention and control of brucellosis in Yantai City.Methods In 2014,an on-site investigation was conducted in a farm where brucellosis occurred in Yantai City,and case searches were conducted on exposed populations in the farm.According to the investigation questionnaire on epidemiology of brucellosis in Shandong Province,general information,clinical manifestation and high-risk behavior exposure information of the cases were collected;blood samples were collected and tested by tiger red plate agglutination test (RBPT) and tube agglutination test (SAT).Brucellosis was diagnosed according to the "Diagnostic Criteria for Brucellosis" (WS 269-2007).Results The first case was male,58 years old,farm worker.A total of 38 suspected cases were found.Eleven patients with positive RBPT and SAT≥1:100 (++) were confirmed cases.The confirmed cases were all male,with a median age of 52 years,ranging from 40 to 60 years old;5 farm workers and 6 construction workers;the onset time was mainly in June and July,a total of 7 cases;clinical manifestations mainly included excessive sweating,muscle and joint pain,fatigue,testicular swelling,etc.Of the 147 sheep in the farm,47 were positive by laboratory tests,accounting for 31.97％,which were the main sources of infection.High-risk exposures for farm workers included hand-delivered births (5 cases) and breeding for livestock (1 case);high-risk exposures for construction workers included entry and exit of sheep houses (6 cases) and handling of supplies in sheep houses (6 cases).Conclusions The epidemic is caused by direct contact with Brucella-infected sheep or caused by respiratory contact with brucellosis contaminated environment.It is necessary to strengthen the health education for prevention and control of the disease in key populations and improve the awareness of the disease.

Objective:To analyze the epidemiological characteristics of human brucellosis (referred to as brucellosis) from 2011 to 2018 in Yantai City, and to provide scientific basis for formulating and adjusting brucellosis prevention and control strategies.Methods:Descriptive epidemiological method was used to analyze the monitoring data and epidemiological survey data (time, area, population distribution and treatment behavior) of brucellosis in Yantai from 2011 to 2018.Results:From 2011 to 2018, 795 cases of brucellosis were reported in Yantai, with an annual incidence of 1.42/100 000 and no deaths. Most of the cases were sporadic, accounting for 92.20% (733/795). The incidence peak was from March to August, accounting for 67.80% (539/795). In addition to Changdao County, cases of brucellosis had been reported in 12 counties (cities, districts). The incidence rate of the top three counties (cities, districts) were 5.20/100 000 (369 cases, accounting for 46.42%) in Laizhou City, 2.13/100 000 (97 cases, accounting for 12.20%) in Zhaoyuan City, and 1.77/100 000 (62 cases, accounting for 7.80%) in Penglai City. The male and female sex ratio was 2.82 to 1.00 (587 to 208). The age of onset was mainly 40 - 69 years old, accounting for 79.62% (633/795). Occupation was mainly farmers, accounting for 83.90% (667/795). Cases were mainly found in local medical institutions, accounting for 89.56% (712/795). The average interval between onset and diagnosis was 17 days, the longest was 40 days in 2012, and the shortest was 12 days in 2018.Conclusions:From 2011 to 2018, except Changdao County, 12 counties (cities and districts) in Yantai City had reported brucellosis cases. The incidence peak was in spring and summer, mainly in middle-aged and elderly people, so we should carry out targeted prevention and control strategies for different areas and key populations.

Objective:To understand the epidemiological characteristics of human brucellosis in Yantai City, Shandong Province, and to provide scientific basis for the formulation and adjustment of brucellosis prevention and control strategy.Methods:The epidemic data, demographic data and case data of human brucellosis in Yantai City in 2019 were collected from the National Health Insurance Disease Control Information System and the epidemiological case survey of brucellosis in Shandong Province. Descriptive epidemiological method was used to analyze the three distribution characteristics, clinical characteristics and infection routes of brucellosis.Results:In 2019, 158 cases of brucellosis were reported in Yantai City, with an incidence rate of 2.22/100 000 and no deaths. The incidence peak was from April to June, accounting for 43.67% (69/158). In addition to Changdao County, 12 other cities and districts had reported brucellosis cases, and Laizhou City had the largest number of reported cases, accounting for 39.87% (63/158). The ratio of men to women was 2.1 ∶ 1.0 (107 ∶ 51). The age of onset was mainly 40 - 69 years (75.95%, 120/158). Farmer was the main occupation, accounting for 83.54% (132/158). The main clinical manifestations were fever (114 cases), muscle and joint pain (107 cases), fatigue (95 cases), hyperhidrosis (85 cases). Patients had a clear history of livestock contact accounted for 58.86% (93/158). The main contact ways were breeding (68 cases) and slaughter (26 cases). Protective measures were taken in 18.28% (17/93) of the patients, and wearing gloves was the most common protective measure, accounting for 76.47% (13/17). The rate of hand washing after contact was 91.40% (85/93), of which 37.65% (32/85) were washed only with water and 62.35% (53/85) were washed with soap. The percentage of changing laundry after contact was 82.80% (77/93).Conclusions:The awareness and ability of personal protection of brucellosis key population in Yantai City are low. Improving the effectiveness of health education and behavior intervention is an important measure for prevention and control of the disease in the future.

Objective:To investigate and analyze a human brucellosis (hereinafter referred to as brucellosis) in Fushan District, Yantai City of Shandong Province, and to provide scientific basis for study the main risk factors and doing a good job in brucellosis prevention and control.Methods:Collect the epidemic data of one human brucellosis in Fushan District, Yantai City in 2017. The information comes from the infectious disease report information management system, the epidemiological case questionnaire of brucellosis in Shandong Province, and the medical records of medical institutions. The epidemic situation, cases and epidemiological investigation results were analyzed retrospectively.Results:Serological tests were carried out among 48 close contacts of the reported case and workers in the same village. Among the 3 positive cases, 2 cases had symptoms and positive bacterial culture results, which were diagnosed as confirmed cases. One patient was asymptomatic and negative bacterial culture, and was diagnosed as recessive infection. All of the three confirmed cases and one recessive infection involved in the epidemic had a history of close contact with infected animals, and without protective measures. The serological examination of 70 key people in the district was carried out and the results were all negative. A total of 166 sheep blood samples were collected, including 21 positive samples.Conclusions:The infectious source of this outbreak is the non-quarantine infected sheep. The main exposure factor is personal unprotected exposure to infected sheep. The key of prevention and control is to strengthen the monitoring and quarantine management of brucellosis among livestock, to improve the personal protection consciousness and ability of key population, and to improve the diagnosis ability of medical institutions in low epidemic areas.