Rickettsia felis in Xenopsylla cheopis, Java, Indonesia

Rickettsia typhi and R. felis, etiologic agents of murine typhus and fleaborne spotted fever, respectively, were detected in Oriental rat fleas (Xenopsylla cheopis) collected from rodents and shrews in Java, Indonesia. We describe the first evidence of R. felis in Indonesia and naturally occurring R. felis in Oriental rat fleas.     

Rickettsial infections and fever, Vientiane, Laos

Rickettsial diseases have not been described previously from Laos, but in a prospective study, acute rickettsial infection was identified as the cause of fever in 115 (27%) of 427 adults with negative blood cultures admitted to Mahosot Hospital in Vientiane, Laos. The organisms identified by serologic analysis were Orientia tsutsugamushi (14.8%), Rickettsia typhi (9.6%), and spotted fever group rickettsia (2.6% [8 R. helvetica, 1 R. felis, 1 R. conorii subsp. indica, and 1 Rickettsia "AT1"]). Patients with murine typhus had a lower frequency of peripheral lymphadenopathy than those with scrub typhus (3% vs. 46%, p<0.001). Rickettsioses are an underrecognized cause of undifferentiated febrile illnesses among adults in Laos. This finding has implications for the local empiric treatment of fever.     

Rickettsia felis infection, Tunisia

We report, for the first time, serologic evidence of Rickettsia felis and R. aeschlimannii infections acquired in Tunisia from 1998 to 2003. We found that most patients with antibodies against both R. conorii and R. typhi had serologic evidence of R. felis infection.     

Rickettsia felis in Fleas, Southern Ethiopia, 2010

TO THE EDITOR: Fleas (order Siphonaptera) are obligate hematophagous insects. They are laterally flattened, holometabolous, and wingless ectoparasites. More than 2,500 species of flea, belonging to 16 families and 238 genera, have been described. A minority of these genera live in close association with humans (synanthropic), including fleas of these species: Pulex irritans, Ctenocephalides felis, Ctenocephalides canis, Xenopsylla cheopis, Nosopsyllus fasciatus, Echidnophaga gallinacea, and Tunga penetrans (1). Many fleas are capable of transmitting the following pathogens to their hosts: bacteria (e.g., Rickettsia typhi, R. felis, Yersinia pestis, and many Bartonella spp.); viruses (e.g., myxoma virus); protozoa (e.g., Trypanosoma spp.); or helminths (e.g., Hymenolepis spp.) (2). Ctenocephalides spp. fleas are of special interest as main reservoirs and vectors of R. felis, because this agent causes an emerging disease, fleaborne rickettsiosis. The distribution and prevalence of this disease have not been well studied. Symptoms of this disease range from mild to moderate and include fever, cutaneous rash, and sometimes an inoculation eschar (3,4). R. felis can also infect at least 10 other species of arthropods, including P. irritans fleas, trombiculid and mesostygmata mites, hard and soft ticks, and booklice (5,6).     

天津市农牧地区2007--2009年莫氏立克次体、横赛巴尔通体、恙虫病东方体血清流行病学调查

目的 分析天津市农牧地区高危人群蚤传及螨传立克次体病流行趋势.方法 2007-2009年,利用现场流行病学调查方法,以农户为单位随机调查天津地区直属的8个区(县)从事农牧业的人群,并现场采集886份血液标本,采用微量间接免疫荧光检测人群莫氏立克次体、横赛巴尔通体及恙虫病东方体特异IgG抗体,并分析比较不同年份、地区、性别及年龄组人群抗体阳性率变化趋势.结果 3种立克次体抗体阳性率均呈上升趋势.其中莫氏立克次体阳性率变化范围为5.0%～58.2%;横赛巴尔通体为2.6%～14.5%;恙虫病东方体为1.8%～39.8%.3种病原体阳性率较高的地区主要集中在天津市东南部及中部近海低海拔地区.结论 天津地区农牧人群普遍存在蚤传及螨传立克次体感染,并且有逐年上升趋势.

Abstract：

Objective To study the sero-epidemiological starus regarding Rickettsia (R.) typhi,Bartonella (B.) henselae and Orientia (O.) tsutsugamushi in farmers from rural areas of Tianjin.Methods Field epidemiological surveys were performed in 8 districts (county) of Tianjin city from 2007 to 2009.886 farmers were randomly recruited and their serum samples collected to detect the specific antibodies of R.typhi,B.henselae and O.tsutsugamushi by micro-indirect immunoflorescence (IFA).Results The total antibody positive rates of R.typhi increased from 5.0% to 58.2% while B.heaselae had an increase from 2.6% to 14.5% and O.tsutsugamushi increased from 1.8% to 39.8%.Geographic distribution showed that farmers living in the central and southeast areas were higher than that in other areas.Conclusion Infections of both R.typhi,B.henselae and O.tsutsugamushi in farmers from Tianjin areas were popular and the antibody positive rates ofR.typhi,B.henselae and O.tsutsugamushi had an annual increase.     

Flea-borne rickettsioses: ecologic considerations.

Ecologic and economic factors, as well as changes in human behavior, have resulted in the emergence of new and the reemergence of existing but forgotten infectious diseases during the past 20 years. Flea-borne disease organisms (e.g., Yersinia pestis, Rickettsia typhi, R. felis, and Bartonella henselae) are widely distributed throughout the world in endemic-disease foci, where components of the enzootic cycle are present. However, flea-borne diseases could reemerge in epidemic form because of changes in vector-host ecology due to environmental and human behavior modification. The changing ecology of murine typhus in southern California and Texas over the past 30 years is a good example of urban and suburban expansion affecting infectious disease outbreaks. In these areas, the classic rat-flea-rat cycle of R. typhi has been replaced by a peridomestic animal cycle involving, e.g., free-ranging cats, dogs, and opossums and their fleas. In addition to the vector-host components of the murine typhus cycle, we have uncovered a second typhuslike rickettsia, R. felis. This agent was identified from the blood of a hospitalized febrile patient and from opossums and their fleas. We reviewed the ecology of R. typhi and R. felis and present recent data relevant to the vector biology, immunology, and molecular characterization and phylogeny of flea-borne rickettsioses.     

Rickettsia felis in Fleas, Germany

Among 310 fleas collected from dogs and cats in Germany, Rickettsia felis was detected in all specimens (34) of Archaeopsylla erinacei (hedgehog flea) and in 9% (24/226) of Ctenocephalides felis felis (cat flea). R. helvetica was detected in 1 Ceratophyllus gallinae (hen flea).     

Human Rickettsia felis infection, Canary Islands, Spain

We report the first cases of human infection by Rickettsia felis in the Canary Islands. Antibodies against R. felis were found in 5 adsorbed serum samples from 44 patients with clinically suspected rickettsiosis by Western blot serology. Fleas from 1 patient's dog were positive for R. felis by polymerase chain reaction.     

Spotted fever group and typhus group rickettsioses in humans, South Korea

The presence of the nucleic acid of the spotted fever group (SPG) and typhus group (TG) rickettsiae was investigated in 200 serum specimens seropositive for SFG rickettsiae by multiplex-nested polymerase chain reaction with primers derived from the rickettsial outer membrane protein B gene. The DNA of SFG, TG, or both rickettsiae was amplified in the 24 serum specimens, and sequence analysis showed Rickettsia conorii, R. japonica, and R. felis in the specimens. R. conorii and R. typhi were found in 7 serum specimens, which indicated the possibility of dual infection in these patients. These findings suggest that several kinds of rickettsial diseases, including boutonneuse fever, rickettsialpox, R. felis infection, and Japanese spotted fever, as well as scrub typhus and murine typhus, are occurring in Korea.     

Seroepidemiology of rickettsial infections in Morocco

The prevalence of antibodies reactive withRickettsia conorii, Rickettsia typhi, Coxiella burnetii andEhrlichia chaffeensis was investigated using indirect immunofluorescence (IFA) test on human sera obtained from 300 blood donors in Casablanca and 126 sera obtained from clinical laboratories in Fez. In sera from Casablanca, antibodies reactive at titers >=1: 32 were found againstR. conorii (7%), andR. typhi (1.7%), but not againstE. chaffeensis. In the sera from Fez, antibodies were also detected againstR. conorii (5.6%),R. typhi (4%), but not againstE. chaffeensis. By Western immunoblotting, seroprevalence forR. conorii was in Casablanca and 4.8% in Fez. Antibodies reactive at titers >=1:50 againstC. burnetii (phase II) were present in sera from Casablanca (1%) and Fez (18.3%).Abbreviations IFA Immunofluorescence assay - MSF Mediterranean spotted fever - PBS Phosphate-buffered saline     

Rickettsia felis as emergent global threat for humans

Rickettsia felis is an emergent pathogen belonging to transitional group rickettsiae. First described in 1990, R. felis infections have been reported to occur worldwide in fleas, mammals, and humans. Because clinical signs of the illness are similar to those of murine typhus and other febrile illnesses such as dengue, the infection in humans is likely underestimated. R. felis has been found throughout the world in several types of ectoparasites; cat fleas appear to be the most common vectors. R. felis infection should be considered an emergent threat to human health.     

浙江省人和家畜蜱媒传染病血清流行病学调查

目的 了解浙江省农村人群与主要家畜蜱媒传染病病原体感染的情况.方法 按地理位置和蜱媒传染病病原体历史检测情况,选择浙西北丘陵区的安吉县、浙中丘陵盆地区的金东区和浙东盆地低山区的天台县为调查点,采集3个调查点农村人群和家畜血标本,以间接免疫荧光法检测黑龙江立克次体、恙虫病东方体、莫氏立克次体、嗜吞噬无形体、查菲埃立克体、巴尔通体、海南立克次体和贝纳柯克斯体8种常见蜱媒传染病病原体IgG抗体.结果 3个调查点共检测683份血清标本,包括579份人标本和104份家畜标本(牛53份、羊51份),不同地区恙虫病东方体、莫氏立克次体、查菲埃立克体、贝纳柯克斯体4种病原体抗体阳性率差异有统计学意义(P值均等于0.000).人血清标本8种病原体IgG抗体均检出,阳性率最高的分别是莫氏立克次体(20.7%)、巴尔通体(10.9%)和贝纳柯克斯体(5.5%),其中莫氏立克次体抗体阳性率随年龄增长而增加.家畜血清标本除嗜吞噬无形体外其余7种病原体IgG抗体均检出,阳性率最高的是莫氏立克次体(69.2%)、巴尔通体(51.0%)和海南立克次体(22.1%),不同家畜抗体阳性情况不同.结论 浙江省不同地区农村人群与家畜中广泛存在多种蜱媒传染病病原体的感染,特别是莫氏立克次体、巴尔通体、海南立克次体和贝纳柯克斯体抗体阳性率较高.     

Prevalence of rodent and mongoose leptospirosis on the Island of Oahu.

Sporadic occurrences of human leptospirosis in recent years throughout the State of Hawaii have resulted in at least one death. Because of the apparent association of rodents and possibly mongooses with human leptospiral infections, a survey for leptospirosis was conducted among rodents as well as mongooses on Oahu. No such work had been recorded since a survey of rodents and mongooses for leptospirosis 31 years ago. In the current work, the prevalence of rodent and mongoose leptospirosis in the districts of Oahu was determined by the kidney-culture method. A serologic study of the rodents and mongooses subjected to kidney culturing was also conducted by use of the microscopic slide agglutination test. There were 1.2 times as many kidney culture results that were positive as serologic results. High prevalence of rodent leptospirosis were found where there was considerable rainfall or fresh surface water such as from streams. The overall leptospirosis prevalence for rodents was 23.4 percent, and for mongooses it was 23.0 percent. The Norway rat (Rattus norvegicus) had the highest infection rate, 33.3 percent, and the predominant (72.2 percent) organism in these infections was Leptospira icterohaemorrhagiae, which causes Weil''s disease in man. Observations of rodent leptospirosis recorded 31 years ago were compared with results of the current study. The mongoose (Herpestes auropunctatus) is the preeminent carrier of Leptospira sejroe, a serotype that generally causes a mild form of leptospirosis in man.     

A comparison of hip fracture incidence among native Japanese, Japanese Americans, and American Caucasians

Hip fracture incidence rates among men and women of Japanese ancestry living on Oahu, Hawaii, from 1979 to 1981 were compared with rates for Japanese living on Okinawa, Japan, from 1984 to 1985. Both rates were further compared with those for various American Caucasian populations, including that of Rochester, Minnesota, from 1978 to 1982. Age-specific and cumulative (age 50-84 years) hip fracture rates among persons of Japanese ancestry were approximately half that of Caucasians for both sexes. Although diet and other cultural attributes of the Oahu group have become more westernized than the Okinawan population, there were no detectable differences in hip fracture rates between Oahu and Okinawa Japanese. Additional studies are needed to determine whether the observed differences in fracture rates between Caucasians and Japanese might be related to differences in bone mass, body size, frequency of falls, or other factors.     

Trends in birth defects for a Hawaiian population exposed to heptachlor and for the United States

The 1980-1982 milk supply contamination on the island of Oahu, Hawaii, by the insecticide heptachlor offered an opportunity to investigate the possible human teratogenicity of this organochlorine. An analysis of incidence rates for 23 major congenital malformations, derived from hospital-generated data collected by the Birth Defects Monitoring Program of the Centers for Disease Control, failed to show any remarkable rate increase on Oahu in 1981-1983, based on comparisons with the rates for previous time periods on this island and with the rates for two unexposed populations (the other Hawaiian islands and the total U.S.). A rise in the rates of cardiovascular malformations and hip dislocation was apparent but antedated the exposure. These results suggest that no major rate increase for malformations recognized at birth resulted from the heptachlor contamination on Oahu. However, misclassification of exposure status in this study may have obscured a more moderate effect.     

The seroprevalence of ten zoonoses in two villages of Crete,Greece

The seroprevalence and incidence of 10 zoonoses due toRickettsia typhi, R. conorii, Coxiella burnetii, Burcella sp.,Borrelia sp.,Toxoplasma sp.,Leishmania sp.,Entamoeba histolytica, Echinococcus granulosus andFasciola hepatica were studied in an animal husbandry and a farming village in Crete, Greece. The serum conversion incidence of each infectious agent was determined by testing 2 blood samples, collected in 1985 and in 1987. The surveillance was conducted using detailed transparent maps of the 2 villages studied, on which epidemiological data were interrelated to the results obtained from the serological tests. Thus the importance and spread of each infection were visualized.C burnetii, Toxoplasma sp.,R. conorii, andE. granulosus, were the most common infectious agents encountered during this study.     

Retired and former asbestos workers in Hawaii

In 1979, a pilot survey defined respiratory status and unmet health care needs of retired and former male asbestos workers in Hawaii. Of 1,401 identified subjects, 741 were contacted and 411 were interviewed. Forty-five subjects were between 39 and 54 years of age; 208, between 55 and 64; and 158, age 65 or more. They represented the main ethnic groups--Caucasian, Chinese, Filipino, Hawaiian and part-Hawaiian, and Japanese--on Oahu. Most subjects had had significant exposure to asbestos in a shipyard, and 83% were current nonsmokers (160 had never smoked, and 111 were ex-smokers for ten years or more). Taking age and ethnicity into account, our group had more chronic respiratory and gastrointestinal problems than the comparable male population of Oahu in 1979, but fewer such problems than active shipyard workers elsewhere. These problems related primarily to current smoking status and secondarily to the length of asbestos exposure. Health care was available, but former workers used it less than retirees, despite having more symptoms. Very few abnormalities were reported by the subjects on their chest X-rays, pulmonary function tests, and sputum cytology performed elsewhere. These findings are compared to those of other shipyards, and support the hypothesis that the biological effects of asbestos exposure are generally mild in Hawaii.     

Dengue fever, Hawaii, 2001-2002

Autochthonous dengue infections were last reported in Hawaii in 1944. In September 2001, the Hawaii Department of Health was notified of an unusual febrile illness in a resident with no travel history; dengue fever was confirmed. During the investigation, 1,644 persons with locally acquired denguelike illness were evaluated, and 122 (7%) laboratory-positive dengue infections were identified; dengue virus serotype 1 was isolated from 15 patients. No cases of dengue hemorrhagic fever or shock syndrome were reported. In 3 instances autochthonous infections were linked to a person who reported denguelike illness after travel to French Polynesia. Phylogenetic analyses showed the Hawaiian isolates were closely associated with contemporaneous isolates from Tahiti. Aedes albopictus was present in all communities surveyed on Oahu, Maui, Molokai, and Kauai; no Ae. aegypti were found. This outbreak underscores the importance of maintaining surveillance and control of potential disease vectors even in the absence of an imminent disease threat.