[Outbreaks of tuberculosis in facilities used by an unspecified number of people near a train station - problems regarding tuberculosis in urban areas ].

OBJECTIVES: To report on the mass outbreak of tuberculosis (TB) in an urban area and to discuss current issues regarding the problem of TB in the metropolis. MATERIALS AND METHODS: Case studies were mainly carried out. Discussions on the route of infection are based on the results of DNA fingerprinting analysis for M. tuberculosis and on information obtained by epidemiological research. RESULTS: In an approximately 500-meter vicinity around Kawasaki Station in Kawasaki City, nine incidences of people contracting TB were reported during the period of one year and five months starting February 2005. Seven of the nine patients were resistant for streptomycin, and the tubercle bacilli of five patients showed identical patterns based on DNA fingerprinting analysis. These nine patients were relatively young, ranging from 16 years to 55 years in age, and three of the patients were homeless. The area for daily activities for all nine patients is a neighborhood of Kawasaki Station. Based on results from an epidemiologic survey, it is suspected that nine patients had come into contact with each other TB patient in places such as "Net cafes" before they developed TB. DISCUSSION: Based on the epidemiological and bacteriological results, the route of infection related to this series of TB outbreak is considered to be facilities used by an unspecified number of people such as "Net cafes." Such "Net cafes" are open 24 hours a day and are used by an unspecified number of people, who go to such places to Internet or enjoy comic books. Recently, there are many "Net cafes" in the city, and has become to be used as temporary places to sleep, not only by young people but also by socially vulnerable people, such as the homeless. This study suggests that infection can happen easily once someone begins to discharge TB bacilli in such environments, due to young people, who for the most part are not infected with TB bacilli, and high-risk people, who have higher probability of developing the disease, sharing a closed space for a long period of time. Such social environments may also affect the distribution of TB to lean towards urban areas. The TB control program in the metropolis should be planned and carried out giving consideration to social aspects.

Geographical distribution for malignant neoplasm of the pancreas in relation to selected climatic factors in Japan.

BACKGROUND: Malignant neoplasm of the pancreas has become one of the leading causes of death from malignant neoplasm in Japan (the 5th in 2003). Although smoking is believed to be a risk factor, other risk factors remain unclear. Mortality from malignant neoplasm of the pancreas tends to be higher in northern Japan and in northern European countries. A recent study reported that standardized mortality ratios (SMRs) for malignant neoplasm of the pancreas were negatively correlated to global solar radiation level. People residing in regions with lower solar radiation and lower temperatures may be at higher risk of development of malignant neoplasm of the pancreas. Therefore, this study aimed to examine the relationship between SMRs for malignant neoplasm of the pancreas and climatic factors, such as the amount of global solar radiation and the daily maximum temperature in Japan. RESULTS: The study used multiple linear regression models. Number of deaths and demographic data from 1998 to 2002 were used for the calculation of SMR. We employed mesh climatic data for Japan published in 2006 by the Japan Meteorological Agency. Regression coefficients for the amount of global solar radiation and the daily maximum temperature in males were -4.35 (p = 0.00034) and -2.81 (p < 0.0001) respectively, and those in females were -5.02 (p < 0.0001) and -1.87 (p < 0.0001) respectively. Increased amount of global solar radiation or daily maximum temperature was significantly related to the decreased SMRs for malignant neoplasm of the pancreas in both males and females. CONCLUSION: This study suggested that low solar radiation and low temperature might relate to the increasing risk of malignant neoplasm of the pancreas. Use of group data has a limitation in the case of evaluating environmental factors affecting health, since the impact of climatic factors on the human body varies according to individual lifestyles and occupations. Use of geographical mesh climatic data, however, proved useful as an index of risk or beneficial factors in a small study area. Further research using individual data is necessary to elucidate the relationship between climatic factors and the development of malignant neoplasm of the pancreas.

Geographical pattern of malignant neoplasm by cluster analysis using standardized mortality ratios (SMRs) in Ibaraki Prefecture, Japan.

We investigated the geographical patterns of mortality from eight (males)/ten (females) sites of malignant neoplasm, using cluster analysis with Standardized Mortality Ratios (SMRs), and examined the relationship between the mortality structure and urbanization. To explore the geographical tendencies is important for the prevention of cancers; such as noticing risk factors associated with regional variance. The death rates, by site, gender and age from 1990 to 1994 in Japan, were obtained from Vital Statistics. The deaths and population in municipalities were obtained from "Population of Ibaraki Prefecture". These were represented as averaged values in five-year periods. As an indicator of urbanization and mortality structure, the population density of municipalities and the overall rank scores of SMRs were used, respectively. Cluster analysis formed some distinctive structures. For males, Cluster 1 included four municipalities and three of these were located in the mountainous area in northwest Ibaraki, characterized by high SMRs from bone marrow. Cluster 5 consisted of the mid-south areas, characterized by high SMRs from stomach cancer. For females, the clusters seemed to be characterized by SMRs from esophagus cancer. An association between mortality structure and urbanization was found for females, 0.364 (p<0.01), but not for males, 0.162 (p=0.14).

[Comparison between HIV-1-infected hemophiliacs and non-hemophiliacs on survival and clinical courses after starting highly active antiretroviral therapy].

In order to investigate the long-term prognosis and clinical efficacy of highly active antiretroviral therapy (HAART) in HIV-1-infected hemophiliacs, we compared clinical courses of 69 HIV-1-infected hemophiliacs and 29 non-hemophiliacs all of whom were asymptomatic between 1990 and 1993. Changes of CD4 count during 1990 through 2000 in both groups were not significantly different. The time to death due to AIDS in both groups were also not significantly different. The major causes of death not related to AIDS in hemophiliacs were bleeding, liver cirrhosis, and liver cancer. A total of 55 (39 hemophiliacs and 16 non-hemophiliacs) out of 98 patients survived in 1997. Since then, the 28 hemophiliacs and the 12 non-hemophiliacs received HAART. Although the percentage of patients whose viral loads (VL) decreased to below undetectable level (VL < 400 copies/ml) by the initial HAART regimens without saquinavir were not significantly different, continuation of the same regimens in the hemophiliacs were significantly longer than non-hemophiliacs (84 weeks vs. 51 weeks, p < 0.05). From starting HAART to July 2000, 35.7% of the hemophiliacs were changed regimens three times or more. That is higher prevalence comparing with non-hemophiliacs of 16.7%. This study suggests that there might be the patient group who have to been changed HAART regimens frequently in the hemophiliacs.