Scrub typhus develops after the individual is bitten by a trombiculid mite infected with Orientia tsutsugamushi. Since it has been reported that pneumonia is frequently observed in patients with scrub typhus, we investigated whether intranasal (i.n.) vaccination with the outer membrane protein of O. tsutsugamushi (OMPOT) would induce a protective immunity against O. tsutsugamushi infection. It was particular interest that when mice were infected with O. tsutsugamushi, the bacteria disseminated into the lungs, causing pneumonia. The i.n. vaccination with OMPOT induced IgG responses in serum and bronchoalveolar lavage (BAL) fluid. The anti-O. tsutsugamushi IgA Abs in BAL fluid after the vaccination showed a high correlation of the protection against O. tsutsugamushi. The vaccination induced strong Ag-specific Th1 and Th17 responses in the both spleen and lungs. In conclusion, the current study demonstrated that i.n. vaccination with OMPOT elicited protective immunity against scrub typhus in mouse with O. tsutsugamushi infection causing subsequent pneumonia.

BACKGROUND: The zoonotic disease Q fever is caused by Coxiella burnetii and usually affects high-risk human populations. We conducted a serological survey of dairy cattle farmers in Korea to determine seroreactivity and identify risk factors for C. burnetii infection. METHODS: This cross-sectional study included 1,824 of 7,219 dairy cattle farms (25.3%) in the study region. The selected dairy cattle farmers visited the nearest public health centers or branches with completed questionnaires. Serum samples from the farmers were tested using an indirect immunofluorescence assay to detect phase II C. burnetii immunoglobulin (Ig) G or M antibodies. RESULTS: A total of 1,222 dairy cattle farmers from 784 dairy cattle farms (43.0%) participated in this study, and 11.0% (134/1,222) exhibited seroreactivity, defined as a phase II antigen IgG or IgM titer ≥ 1:16. In the multivariate analysis, male sex, residence in Gyeonggi Province, a larger herd size, and ocular/oral contact with birth products during calf delivery were significantly associated with a higher risk of C. burnetii infection. Furthermore, the risk was significantly lower among farmers who always wore protective gloves while cleaning cattle excretion, compared to those who sometimes or rarely wore protective gloves. CONCLUSION: Dairy cattle farmers should exercise caution by avoiding ocular/oral contact with birth products during calf delivery and by using protective equipment (including gloves).
Agriculture ; Animals ; Antibodies ; Cattle* ; Coxiella burnetii* ; Coxiella* ; Cross-Sectional Studies ; Farmers* ; Fluorescent Antibody Technique, Indirect ; Gloves, Protective ; Gyeonggi-do ; Humans ; Immunoglobulin G ; Immunoglobulin M ; Immunoglobulins ; Korea* ; Male ; Multivariate Analysis ; Parturition ; Public Health ; Q Fever* ; Risk Factors* ; Serologic Tests ; Zoonoses

OBJECTIVES: Q fever is a zoonotic disease that occurs worldwide; however, little is known about its prevalence in South Korea. We attempted to determine the prevalence of Q fever seroreactivity among Korean slaughterhouse workers and the risk factors for seroreactivity according to the type of work. METHODS: The study was conducted among 1503 workers at a total of 73 slaughterhouses and 62 residual-product disposal plants. During the study period, sites were visited and surveys were administered to employees involved in slaughterhouse work, and serological tests were performed on blood samples by indirect immunofluorescence assays. Serological samples were grouped by job classification into those of slaughter workers, residual-product handlers, inspectors and inspection assistants, and grading testers and testing assistants. Employee risk factors were analyzed according to the type of work. RESULTS: Out of 1481 study subjects who provided a blood sample, 151 (10.2%) showed reactive antibodies. When these results were analyzed in accordance with the type of work, the result of slaughter workers (11.3%) was similar to the result of residual-product handlers (11.4%), and the result of inspectors and assistants (5.3%) was similar to the result of grading testers and assistants (5.4%). Among those who answered in the affirmative to the survey question, “Has there been frequent contact between cattle blood and your mouth while working?” the proportions were 13.4 and 4.6%, respectively, and this was identified as a risk factor that significantly varied between job categories among slaughterhouse workers. CONCLUSIONS: This study found a Q fever seroreactivity rate of 10.2% for slaughterhouse workers, who are known to be a high-risk population. Contact with cattle blood around the mouth while working was the differential risk factor between job categories among slaughterhouse workers.
Abattoirs* ; Animals ; Antibodies ; Cattle ; Classification ; Coxiella burnetii ; Fluorescent Antibody Technique, Indirect ; Korea* ; Mouth ; Prevalence ; Q Fever* ; Risk Factors ; Serologic Tests ; Zoonoses

BACKGROUND: In this study, we compared various methods of taxonomic identification of Bacillus strains: biochemical methods, 16S rRNA gene sequencing, and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). We also developed a pathogen- isolate resource database, thus increasing the identification rate when using MALDI-TOF MS. METHODS: Thirty Bacillus strains were obtained from the NCCP (National Culture Collection for Pathogens) and were identified using the VITEK 2 system (bio-Mérieux, France), API kit (bioMérieux, France), 16S rRNA gene sequencing, and MALDI-TOF MS. The pathogenicity of Bacillus cereus was confirmed through the identification of virulent genes using a multiplex PCR, and both protein extraction for protein profiling in MALDI-TOF MS and repetitive-sequence fingerprinting were performed. RESULTS: The identification rates at the species level were 40%, 80%, and 76.3% for the VITEK 2 system (bioMérieux), 16S rRNA gene sequencing, and MALDI-TOF MS, respectively. When the major spectrum-profiling dendrogram was compared with the phylogenetic tree, which was constructed based on the 16S rRNA gene sequences and rep-PCR fingerprinting, the classifications were confirmed to be effective. CONCLUSION: Identification of Bacillus strains using MALDI-TOF MS was more effective than that using the VITEK 2 system (bioMérieux), but was similar to that using 16S rRNA gene sequencing. Continual addition to a proteome-based database can result in increased identification rates for MALDI-TOF MS.
Bacillus cereus ; Bacillus* ; Classification ; Dermatoglyphics ; Genes, rRNA ; Mass Spectrometry* ; Multiplex Polymerase Chain Reaction ; Trees ; Virulence

Orientia tsutsugamushi (O. tsutsugamushi), which is endemic to an Asia-Pacific region, has increased its incidence and caused annually around 10 thousand patients infected with scrub typhus in Korea in the past several years. In the present study, we isolated 44 O. tsutsugamushi from the patients with febrile illness accompanied with or without an eschar in Gyeongsangnam-do, Korea. These isolates were characterized by genetic analysis of the major outer membrane protein, the 56-kDa type-specific antigen (tsa56), which is unique to O. tsutsugamushi. Two types of sequences of tsa56, designated by JJ1 and JJ2, were determined from 37 and 7 isolates of the 44 isolates, respectively. JJ1 and JJ2 showed 74.7~90.8% identity in nucleotide sequence and 66.1~90.5% identity in amino acid sequence with 33 reference strains except for Boryong and Kuroki. JJ1 and JJ2 had 100 and 99.9% nucleotide identity to Boryong strain, and 99.9 and 99.8% to Kuroki, which has been known to be similar to Boryong, respectively. In addition, they showed 77.9~ 81.4% nucleotide identity with the cluster of Gilliam-related genotypes, whereas they showed higher nucleotide identity (89.6~90.8%) with the cluster of Karp-related genotypes. To our knowledge, this is the first report to isolate O. tsutsugamushi and characterize their genotype as the Boryong in Jinju and West Gyeongsangnam-do, Korea, even though it has been reported that the Boryong was the predominant genotype in isolates from chiggers, domestic rodents, and patients in the southern part of Korea. Furthermore, our isolates could be useful source to study on the pathophysiology and epidemiology of scrub typhus in Korea.
Amino Acid Sequence ; Base Sequence ; Chungcheongnam-do ; Epidemiology ; Genotype ; Gyeongsangnam-do* ; Humans ; Incidence ; Korea* ; Membrane Proteins ; Orientia tsutsugamushi* ; Rodentia ; Scrub Typhus* ; Trombiculidae

Species identification is an important item to characterize unidentified bacterial pathogens in developing and managing bacterial resources. In this study, unidentified pathogens based on the results of an automated identification system were identified using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALD-TOF MS) and 16S rRNA gene analysis for development of national resources in the National Culture Collection for Pathogens (NCCP) in Korea. A total of 437 unidentified strains from branch banks of the NCCP were collected, and 16S rRNA and dnaJ gene sequencing, as well as MALDI-TOF MS analysis were performed to identify bacterial species. The mass spectra extracted were analyzed. Twelve strains exhibiting less than 98.65% similarity in 16S rRNA gene were selected as the primary candidates for novel species, and 21 strains exhibiting 98.65~99.0% similarity in 16S rRNA gene were selected as possible candidates for novel species. Among them, strain 32, belonging to Dermabacter sp., was finally selected as a possible strain representing a novel species and 14 unidentified bacterial strains using automated phenotypic identification system were newly registered at NCCP. The present study showed that unidentified pathogens using the automated phenotypic identification system were efficiently identified using the combination of MALDI-TOF MS and 16S rRNA gene analysis, and developed to the national resources in NCCP.
Genes, rRNA* ; Korea ; Mass Spectrometry

We investigated the immune response induced by the Francisella (F.) tularensis live vaccine strain (LVS) and the Pohang isolate. After the Balb/c mice were infected intradermally (i.d) with 2 x 10(4) cfu of F. tularensis LVS and Pohang, respectively, their blood and organs were collected at different times; 0, 3, 6, 24, 72, 96, 120 and 168 h after infection. Using these samples, RT-PCR and ELISA analysis were carried out for the comparative study of the cytokines, including TNF-alpha, INF-gamma, IL-2, IL-4, IL-10 and IL-12. In the Pohang-infected mice at 120 h, the liver showed a 53 times higher level of TNF-alpha and a 42 times higher level of IFN-gamma than the respective levels at the early time points after infection. The levels of TNF-alpha and IFN-gamma induced by LVS were 5 times lower than those induced by the Pohang isolate. Also, the organs from the Pohang-infected mice showed higher levels of TNF-alpha, IFN-gamma, IL-10 and IL-12 than the levels in the LVS-infected mice. The blood from the Pohang-infected mice at 120 h revealed about a 40 times increased level of IFN-gamma, and IL-10 was also increased by 4 times at 96 h compared to an early infection time point, while IL-4 was not induced during the whole infection period. These results suggest that F. tularensis may induce a Th1-mediated immune response to in vivo infection and the Pohang isolate has a higher capacity than the LVS to induce an acute immune response in Blab/c mice.
Animals ; *Bacterial Vaccines ; Cytokines/*biosynthesis ; Francisella tularensis/immunology/isolation & purification/*pathogenicity ; Humans ; Interferon-gamma/genetics/metabolism ; Interleukins/genetics/metabolism ; Korea ; Liver/microbiology/pathology ; Mice ; Mice, Inbred BALB C ; Polymerase Chain Reaction ; Tularemia/*diagnosis/*immunology ; Tumor Necrosis Factor-alpha/genetics/metabolism

The aerozolization is one of possible Brucella transmission mechanisms, particularly in air-borne exposed laboratory workers. In this study, seven laboratory workers were potentially exposed to B. abortus via aerosols. Two laboratory workers who sniffed an agar plate several times were considered to be at high risk for acquiring the disease, 5 workers who did not work directly with the strain were be considered at low risk of infection. Prophylactic antibiotics of doxycycline 200 mg/day and rifampin 600 mg/day were offered for 6 weeks in high risk workers and 3 weeks for low risk workers, respectively. Enrolled workers were advised to check for serological testing of Brucella species every 3 weeks during a total period of 12 weeks. Compliance with taking medicine was 57.1% (4/7) and compliance for completing the serological tests was 85.7% (6/7). None of the laboratory workers developed clinical disease or tested positive serologically during 3 months of serological testing and 1 year of clinical follow-up.
Aerosols ; Agar ; Anti-Bacterial Agents ; Brucella ; Brucella abortus ; Chemoprevention ; Compliance ; Doxycycline ; Follow-Up Studies ; Rifampin ; Serologic Tests ; Sprains and Strains

The aerozolization is one of possible Brucella transmission mechanisms, particularly in air-borne exposed laboratory workers. In this study, seven laboratory workers were potentially exposed to B. abortus via aerosols. Two laboratory workers who sniffed an agar plate several times were considered to be at high risk for acquiring the disease, 5 workers who did not work directly with the strain were be considered at low risk of infection. Prophylactic antibiotics of doxycycline 200 mg/day and rifampin 600 mg/day were offered for 6 weeks in high risk workers and 3 weeks for low risk workers, respectively. Enrolled workers were advised to check for serological testing of Brucella species every 3 weeks during a total period of 12 weeks. Compliance with taking medicine was 57.1% (4/7) and compliance for completing the serological tests was 85.7% (6/7). None of the laboratory workers developed clinical disease or tested positive serologically during 3 months of serological testing and 1 year of clinical follow-up.
Aerosols ; Agar ; Anti-Bacterial Agents ; Brucella ; Brucella abortus ; Chemoprevention ; Compliance ; Doxycycline ; Follow-Up Studies ; Rifampin ; Serologic Tests ; Sprains and Strains

Brucellosis is a zoonosis caused by Brucella species. B. melitensis, B. suis, B. abortus and B. canis can infect humans. Recently, as the cases of bovine brucellosis have increased every year in Korea, the cases of human brucellosis have also increased among livestock workers and veterinarians in rural areas, since the first human case was reported in 2003. Because clinical manifestations of the disease are nonspecific and may be very atypical, clinicians and laboratory persons need to be active in using diagnostic tools including polymerase chain reaction in addition to the ordinary culture and serologic tests, and taking an appropriate measure to prevent intralaboratory infection. We report herein our experience in three human brucellosis cases diagnosed by cultures, serologic tests and gene detection.
Animals ; Brucella ; Brucellosis* ; Brucellosis, Bovine ; Cattle ; Humans* ; Korea ; Livestock ; Polymerase Chain Reaction ; Serologic Tests ; Veterinarians