Parasitocenoses in natural foci of hemorrhagic fever with renal syndrome in the Maritime Territory

A complex of possible vectors and reservoirs of infection in nature has been investigated in five different nidi of hemorrhagic fever with the renal syndrome in the Primorje territory. 2455 ixodid ticks, 19 458 trombiculid mites, 10 942 gamasid mites and 2138 fleas were collected from 1700 small mammals. It has been established that every investigated nidus differs in a peculiar specific composition and ratio between small mammals and their ectoparasites.     

Interferon in patients with hemorrhagic fever with renal syndrome

The in vitro production of alpha- and gamma-interferon (IF) by peripheral blood lymphocytes (PBL) and the concentration of serum IF in 50 patients having hemorrhagic fever with renal syndrome (HFRS), as well as the possibility of the formation of spontaneous IF by PBL and the influence of the patient blood plasma on alpha-IF genesis, was studied. The development of HFRS was accompanied by a rise in the level of serum IF with different speed, depending on the severity of the disease with simultaneous suppression of the lymphocytes capacity for alpha- and especially gamma-IF production. In cases of moderate and severe forms of the disease no restoration of the IF system occurred by the moment of discharge from the hospital. In a few patients spontaneous IF in low titers was determined. In cases of the moderate form of the disease in the oligoanuretic period and the severe form of the disease in the oligoanuretic and polyuretic periods the patients' blood plasma essentially suppressed the production of alpha-IF by PBL.     

Epidemiology of hemorrhagic fever with renal syndrome in the north Volga-Viatka region

The results of the ecological and epidemiological study of hemorrhagic fever with the renal syndrome (HFRS) in the Kirov region for the period of 1987-2000 are presented. HFRS morbidity rate varied from 1.3 to 13.7 per 100,000 population, which corresponded to the figures registered in the Volga Vyatka region. Cases of HRFS were mainly (90%) registered in three southern districts of the region. The moderate degree of correlation between morbidity rate and the number of wild mammals (r = 0.55) was established. Periodic morbidity rise occurred every 3 years. In 1998-2000 the contamination of wild mammals with HFRS virus increased and reached 7.6-9.5%. Infection factors connected with everyday human activities somewhat prevailed, industrial and agricultural types of infection constituting 43.8%. Males aged 20-49 years prevailed among the patients. Morbidity rate among urban dwellers exceeded that among town residents.     

气候变化和经济发展对肾综合征出血热发生的影响

肾综合征出血热(hemorrhagic fever with renal syndrome, HFRS)是一种啮齿动物传播的自然疫源性疾病, 危害严重, 已成为全球重要的公共卫生问题。本研究采用数理统计模型及小波分析方法, 对陕西省西安市鄠邑区1984-2016年HFRS的发生与鼠类、气候和经济因素的关系进行分析, 探讨气候和经济因素对HFRS发生的影响。小波分析结果表明, 该地区的HFRS暴发史可能分为两个时期, 推测每个时期具有不同的主要宿主, 在2002年褐家鼠(Rattus norvegicus)可能取代黑线姬鼠(Apodemus agrarius)成为HFRS疫源地的主要宿主。广义可加模型模拟结果表明, HFRS的发生与1984-2001年黑线姬鼠密度间存在极显著非线性效应(F_2.06,9.02 = 102.415, P < 0.01), 两者间显现为正相关; 与2002-2016年的褐家鼠密度间呈正相关(F_1.67,9.02 = 73.929, P < 0.01); HFRS主要宿主的这种变化可能与当地气候变化和经济发展有关: HFRS的发生与年平均温度存在极显著的非线性效应(F_2.93,9.02 = 12.164, P < 0.01), 两者间呈负相关; 同样, HFRS的发生与上一年的国内生产总值(GDP)也存在显著非线性效应(F_1.70,9.02 = 2.917, P < 0.05), 两者间也呈负相关。结构方程模型通过直接和间接的影响途径证明了这种转移机制, 发现温度对HFRS发生有显著的直接负向影响以及通过褐家鼠的间接正向影响; GDP对HFRS发生有直接的负向影响。本研究表明HFRS的发生与气候变化和经济发展相关, 两者均能影响HFRS的暴发, 该结论有助于今后更好地对HFRS疾病进行预防和控制。     

Morbidity and prophylaxis of hemorrhagic fever with renal syndrome in the Republic of Bashkortostan

The brief retrospective analysis of morbidity, epizootological data and preventive measures with respect to haemorrhagic fever with renal syndrome (HFRS) during the whole period of its registration on the territory of the Republic of Bashkortostan along with the structure of HFRS morbidity during epidemic seasons of 1998 and 1999 is presented. The main causes of decreased HFRS morbidity in 1998, its rise in 1999 as well as prognosis for the year 2000 were detected. The level of HFRS morbidity among the population was found to be directly related to the number of rodents and their infection rate. The basic strategy of epidemic control interventions has been proposed.     

Prognosis of the incidence of hemorrhagic fever with the renal syndrome in the Primorsk region]

A study was made of a possibility of prognostication of the number of patients (morbidity per 100 000 residents) with hemorrhagic fever with the renal syndrome in conditions of the Primorsk region. The main factors characterizing this disease were analyzed with the use of the "Minsk-22" computer; these were dynamics of the populations of murine rodents, metereological data, morbidity. A method of prognostication of the number of patients (morbidity) with hemorrhagic fever and a renal syndrome in the Primorsk region for the current year was elaborated.     

青州市2008—2014年肾综合征出血热疫情分析

目的分析2008—2014年青州市肾综合征出血热(以下简称HFRS)疫情的流行规律,为制定有效的预防控制措施提供科学依据。方法采用描述流行病学方法对2008—2014年青州市HFRS疫情资料进行分析。结果2008—2014年青州市共报告HFRS病例220例,年平均发病率为3.40/10万,发病率总体呈上升趋势;发病时间主要集中在2—5月;发病地区以庙子镇、王坟镇、邵庄镇和王府办事处最多,占报告病例数的51.36%;发病年龄以30~60岁青壮年为主,占报告病例数的80.00%(176/220);职业以农民为主,占报告病例数的86.36%(190/220);男女性别比例为2.67∶1(160/60);汉坦病毒(Hantavirus,HV)宿主室内外均以褐家鼠和小家鼠为主,属于家鼠型疫区,春季和秋季鼠HV抗原阳性率分别为2.51%和1.61%。结论青州市2008—2014年HFRS总体呈散发、上升趋势,应采取综合性防治对策,控制该病的传播与蔓延。     

Control of laboratory acquired hemorrhagic fever with renal syndrome (HFRS) in Japan

By the end of 1985, 126 human cases of laboratory acquired hemorrhagic fever with renal syndrome (HFRS) were recorded in Japan. Seroepidemiological studies revealed that laboratory rats exhibited high IFA titers against Hantaan or related viruses at locations where HFRS patients occurred. Laboratory researchers contracted HFRS more frequently than laboratory animal technicians or caretakers, although a laboratory animal caretaker died of the disease. Inhalation of HFRS-virus contaminated air in an animal facility is the likely cause of infection with this virus. Wound infection during animal experiments may be another important route of infection. Infection of laboratory rats can occur by transferring animals from contaminated to other animal facilities. Tissue fragments or cells of transplantable animal tumors are a potential source of spreading the HFRS virus. Eradication of HFRS virus from a contaminated animal facility can be achieved best by elimination of all animals in the room, especially when human HFRS is associated with an infected colony. In some cases, when IFA titers of the sera of the rats tested were low, infection apparently disappeared without instituting any particular control measures other than ordinary procedures for care and management of laboratory animals. HFRS viruses have not yet been eradicated from all animal facilities in Japan. Therefore, serological monitoring of laboratory rats continues.     

Cases of hemorrhagic fever with renal syndrome in Amur Province associated with the rat serotype of the virus

To carry out serodiagnosis and to determine the serotype of the virus causing hemorrhagic fever with the renal syndrome (HFRS), paired sera obtained from 28 HFRS patients, 42 persons with a history of HFRS (1-17 years after convalescence), and 268 serum samples from healthy persons residing at the areas with the natural foci of this infection have been studied by indirect immunofluorescence techniques at the territory of the Amur Province. This study has demonstrated for the first time that, alongside the diseases caused by HFRS virus of serotype Apodemus, HFRS viruses of serotype Rattus and an unidentified serotype serve as the source of infection for the population of the Amur region. The leading role of serotype Rattus in HFRS has been confirmed by the detection of antibodies mainly to this serotype in serum samples taken from convalescents after HFRS and from the healthy population of the areas with the foci of HFRS virus infection.     

Hemophagocytic syndrome associated with dengue hemorrhagic fever

The haemophagocytic syndrome is characterised by systemic proliferation of non-neoplastic histiocytes showing haemophagocytosis resulting in blood cytopenia. It has been described in relation to several viruses earlier. We present three patients with haemophagocytic syndrome (HFS) secondary to dengue haemorrhagic fever (DHF) confirmed by standard laboratory tests. The patients were hospitalized at the University Hospital (Hospital Universitario Ramón González Valencia-HURGV) in Bucaramanga, Colombia, during the past two years. They were all school-aged patients who presented DHF with intense abdominal pain, prolonged fever, hypotension and painful hepatomegaly. Laboratory tests showed thrombocytopenia, anaemia and leukopenia. A calculous cholecystitis was observed in the abdominal ultrasonography, and all bone marrow aspirations showed that platelets, red and white blood cells were phagocyted by histiocytes. According to the International Society of Histiocytosis, SHF is defined and classified in three major categories; the reported cases corresponded to histiocytosis class II, specifically to secondary SHF. Diverse associations of this syndrome correspond to viral infections and some other non-infectious diseases. A difference has been established between primary SHF and secondary SHF. Finally, we emphasize that these three patients had an atypical evolution of FHD, being prolonged fever and persistent abdominal pain the most important symptoms. The authors recommend that a bone marrow aspiration should be carried out as part of the differential diagnosis study in prolonged fever associated with dengue, as there is a possibility that this complication could be secondary SHF.