Seroprevalence of Rickettsia japonica on an Island Where a Korean Patient with Japanese Spotted Fever was First Identified / 감염과화학요법

BACKGROUND: Spotted fever group rickettsiosis occurs worldwide and includes various causative organisms depending on the region and clinical features. In Korea, previous studies have shown that several kinds of spotted fever rickettsiae have been identified in ticks, and in stored sera obtained from febrile patients. Previously, it was difficult to correlate the results of serologic or molecular biologic tests with the clinical or epidemiological features of this disease in humans. In 2004, the first Korean patient with Japanese spotted fever (JSF) was identified on Mueui Island, Incheon, Korea. To estimate the prevalence of JSF and to compare the incidence of JSF with those of other infectious diseases endemic to Korea, we performed a serosurvey of Japanese spotted fever and other rickettsiosis (scrub typhus and murine typhus), hemorrhagic fever with renal syndrome and leptospirosis on the island where the patient had been living. MATERIALS AND METHODS: In October 2004, we performed a seroprevalence survey of Mueui Island where nearly 300 persons resided. There were 91 persons who participated in the survey and answered the questionnaire. The participants included 30 healthy subjects receiving a check up at the Health Promotion Center at Inha University Hospital, and 30 patients with rheumatoid factor as control groups for the serologic tests. RESULTS: Of the 91 residents, only one person showed a positive reaction to R. japonica at a titer of 1:80. IgG antibodies against O. tsutsugamushi were positive at a titer of 1:32 in 3 persons, and those against R. typhi were at 1:32 in 1 person and at 1:64 in 2 persons. Serum IgG antibodies to Hantan virus were positive at a dilution of 1:64 in 2 persons and those to leptospira were negative. All 30 healthy persons and 30 patients with rheumatoid factor in the control group showed negative results in 1:40 diluted sera. CONCLUSION: This study demonstrates that the seroprevalence of R. japonica is not as high in Korea as it is in Japan. Further studies should be performed in a large number of patients, including residents of other islands and the Korean peninsula.

Seroprevalence of Rickettsia japonica on an Island Where a Korean Patient with Japanese Spotted Fever was First Identified / 감염과화학요법

BACKGROUND: Spotted fever group rickettsiosis occurs worldwide and includes various causative organisms depending on the region and clinical features. In Korea, previous studies have shown that several kinds of spotted fever rickettsiae have been identified in ticks, and in stored sera obtained from febrile patients. Previously, it was difficult to correlate the results of serologic or molecular biologic tests with the clinical or epidemiological features of this disease in humans. In 2004, the first Korean patient with Japanese spotted fever (JSF) was identified on Mueui Island, Incheon, Korea. To estimate the prevalence of JSF and to compare the incidence of JSF with those of other infectious diseases endemic to Korea, we performed a serosurvey of Japanese spotted fever and other rickettsiosis (scrub typhus and murine typhus), hemorrhagic fever with renal syndrome and leptospirosis on the island where the patient had been living. MATERIALS AND METHODS: In October 2004, we performed a seroprevalence survey of Mueui Island where nearly 300 persons resided. There were 91 persons who participated in the survey and answered the questionnaire. The participants included 30 healthy subjects receiving a check up at the Health Promotion Center at Inha University Hospital, and 30 patients with rheumatoid factor as control groups for the serologic tests. RESULTS: Of the 91 residents, only one person showed a positive reaction to R. japonica at a titer of 1:80. IgG antibodies against O. tsutsugamushi were positive at a titer of 1:32 in 3 persons, and those against R. typhi were at 1:32 in 1 person and at 1:64 in 2 persons. Serum IgG antibodies to Hantan virus were positive at a dilution of 1:64 in 2 persons and those to leptospira were negative. All 30 healthy persons and 30 patients with rheumatoid factor in the control group showed negative results in 1:40 diluted sera. CONCLUSION: This study demonstrates that the seroprevalence of R. japonica is not as high in Korea as it is in Japan. Further studies should be performed in a large number of patients, including residents of other islands and the Korean peninsula.

Clinical and Epidemiologic Features of Meningococcal Infections in Incheon, Korea / 감염과화학요법

BACKGROUND: Meningococcal diseases occur worldwide and there are several case reports and reports on carriage rates in Korean military personnel. However, there are only few data on meningococcal diseases in the civilian. This study was performed to determine the incidence, clinical features of meningococcal disease, and a pharyngeal carriage rate of meningococcus in nonmilitary persons in metropolitan Incheon, Korea. MATERIALS AND METHODS: Patients with meningococcal diseases were searched by the following methods: discharge diagnosis of 'meningococcal infection' or 'meningococcal meningitis' or 'meningococcal sepsis'; positive cases in bacterial culture of blood or cerebrospinal fluid (CSF); positive meningococcal antigen in CSF. Two university hospitals in Incheon were participated and medical records of the meningococcal infection were reviewed. A survey of pharyngeal carriage of N. meningitidis was done at a high school by throat culture. RESULTS: A total of 15 cases of meningococcal diseases were identified. Ten cases were from Inha University hospital from January 1997 to May 2004, and five cases were from Gacheon Medical School Gil hospital from January 2002 to May 2004. Neisseria meningitidis was isolated in 11 cases and the remaining 4 cases were diagnosed by detecting of meningococcal antigen. The minimal annual incidence rates of meningococcal infection in metropolitan Incheon city ranged from 0.077/ 100,000 to 0.192/100,000. Majority of the patients were under 15 years old and occurred between October to May. The diagnosis was meningitis in 14 patients and sepsis in one patient. Patient with sepsis died but all the other patients recovered.Two among five strains produced beta-lactamase. Throat cultures from 78 high school students showed Neiserria meningitidis in 6 (7.7%) students. CONCLUSION: Epidemiologic data and clinical features were similar to other reports from developed countries. However antimicrobial resistance rate may be higher. Further studies on meningococcal serogroup or sequence type, antimicrobial resistance, and prevalence of antibody against meningococcus are needed.

Clinical and Epidemiologic Features of Meningococcal Infections in Incheon, Korea / 감염과화학요법

BACKGROUND: Meningococcal diseases occur worldwide and there are several case reports and reports on carriage rates in Korean military personnel. However, there are only few data on meningococcal diseases in the civilian. This study was performed to determine the incidence, clinical features of meningococcal disease, and a pharyngeal carriage rate of meningococcus in nonmilitary persons in metropolitan Incheon, Korea. MATERIALS AND METHODS: Patients with meningococcal diseases were searched by the following methods: discharge diagnosis of 'meningococcal infection' or 'meningococcal meningitis' or 'meningococcal sepsis'; positive cases in bacterial culture of blood or cerebrospinal fluid (CSF); positive meningococcal antigen in CSF. Two university hospitals in Incheon were participated and medical records of the meningococcal infection were reviewed. A survey of pharyngeal carriage of N. meningitidis was done at a high school by throat culture. RESULTS: A total of 15 cases of meningococcal diseases were identified. Ten cases were from Inha University hospital from January 1997 to May 2004, and five cases were from Gacheon Medical School Gil hospital from January 2002 to May 2004. Neisseria meningitidis was isolated in 11 cases and the remaining 4 cases were diagnosed by detecting of meningococcal antigen. The minimal annual incidence rates of meningococcal infection in metropolitan Incheon city ranged from 0.077/ 100,000 to 0.192/100,000. Majority of the patients were under 15 years old and occurred between October to May. The diagnosis was meningitis in 14 patients and sepsis in one patient. Patient with sepsis died but all the other patients recovered.Two among five strains produced beta-lactamase. Throat cultures from 78 high school students showed Neiserria meningitidis in 6 (7.7%) students. CONCLUSION: Epidemiologic data and clinical features were similar to other reports from developed countries. However antimicrobial resistance rate may be higher. Further studies on meningococcal serogroup or sequence type, antimicrobial resistance, and prevalence of antibody against meningococcus are needed.