Sequelae of World War II: an outbreak of chronic cutaneous nontuberculous mycobacterial infection among Satowanese islanders.

BACKGROUND: After World War II, residents of Satowan (population, 650 persons), an outer island in the state of Chuuk, Federated States of Micronesia, noted a high prevalence of a chronic, progressive skin disease known locally as "spam." METHODS: Island residents who had chronic, progressive verrucous or keloidal plaques for >3 months were considered case patients. Tissue specimens were obtained for culture, histopathological analysis, mycobacterial polymerase chain reaction (PCR), and comparison with the hsp65 gene of Mycobacterium marinum. We performed a case-control study involving all cases and randomly selected control individuals from the community. RESULTS: A total of 39 case patients were identified, with a median age of 26.0 years (range, 8-82 years); 74.4% were male, and the mean duration of disease was 12.5 years. A total of 98 control individuals were enrolled. Results of all 19 mycobacterial tissue cultures were negative, and histopathological analysis of all 9 lesions showed suppurative granulomatous inflammation with negative results of mycobacterial and fungal stains. In 7 of 9 paraffin-embedded samples, nontuberculous mycobacterial DNA was detected by PCR, and 2 sequenced products had 95% and 87% identity to M. marinum. All case patients were taro farmers (odds ratio, undefined; P < .01), and among taro farmers, when the analysis was controlled for sex, contact with water-filled World War II-era bomb craters was associated with infection (odds ratio, 8.2; P < .01). CONCLUSIONS: "Spam disease" is a chronic, progressive skin disease of high prevalence on Satowan and is associated with taro farming and contact with World War II-era bomb craters. Histopathological and PCR data demonstrate a nontuberculous mycobacterial infection as the cause.

Comparison of serology and isolates for the identification of infecting leptospiral serogroups in Hawaii, 1979-1998.

Laboratory confirmation of leptospirosis is usually accomplished serologically, without isolates, using the microscopic agglutination test (MAT). However, optimal performance of the MAT is dependent on the knowledge of enzootic serogroups and serovars so that an appropriate MAT antigen testing battery can be established. Infecting leptospiral serogroups can be identified serologically without isolates, using the MAT, or by serogrouping of isolates, but little information is available regarding the correlation between these methods. The identification of infecting serogroups for 53 culture-confirmed leptospirosis cases, diagnosed in Hawaii between 1979 and 1998, using serology and culture isolates were compared. The overall agreement between the two methods was good (kappa = 0.71, 95% CI: 0.56, 0.86). However, the agreement varied between serogroups from 0 to 100%. In establishing the prevalence of serogroups, results obtained via MAT serology (in the absence of serogrouped isolates) should be considered presumptive rather than definitive.

Leptospirosis in Hawaii, 1974-1998: epidemiologic analysis of 353 laboratory-confirmed cases.

The epidemiologic characterization of leptospirosis in the United States has been limited by difficulties associated with both case detection and confirmation. In addition, leptospirosis was eliminated from the list of National Notifiable Diseases in 1995. From 1974 until the cessation of national surveillance, Hawaii consistently had the highest reported annual incidence rate in the United States. From 1974 through 1998, 752 leptospirosis cases were reported in the State of Hawaii. Of these, 353 had exposures within the state and were laboratory confirmed. The mean annual incidence rate was 1.29 per 100,000. Cases were predominately male. Rates were highest in rural areas. Occupational exposures diminished over time while recreational exposures increased. This series represents the first large U.S. leptospirosis surveillance report since 1979. With leptospirosis recently being identified as a re-emerging zoonosis, continued national surveillance and case reporting should be reconsidered.