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Thirty percent of 325 sera from Athapaskan Indians in five villages in east-central Alaska were found to be positive for antibodies of California encephalitis virus (CEV) by means of the hemagglutination-inhibition (HI) test, using CEV prototype strain 283 for hemagglutination (HA) preparation. Neutralizing antibodies were detected in 72% of the sera by means of a plaque reduction method, using CEV Jamestown Canyon strain 2235. In these tests, CEV-neutralizing substances were present in all but 1 of 94 persons tested over age 30. The serum of the single exceptional individual was positive in the HI test. Since most of the persons tested had not traveled outside Alaska, serological evidence indicates that exposure to CEV had occurred within the state. Evidence for the occurrence of arboviruses in Alaska has not been reported previously.

In 2001, envelopes loaded with Bacillus anthracis spores were mailed to Senators Daschle and Leahy as well as to the New York Post and NBC News buildings. Additional letters may have been mailed to other news agencies because there was confirmed anthrax infection of employees at these locations. These events heightened the awareness of the lack of understanding of the mechanism(s) by which objects contaminated with a biological agent might spread disease. This understanding is crucial for the estimation of the potential for exposure to ensure the appropriate response in the event of future attacks. In this study, equipment to simulate interactions between envelopes and procedures to analyze the spread of spores from a "payload" envelope (i.e., loaded internally with a powdered spore preparation) onto neighboring envelopes were developed. Another process to determine whether an aerosol could be generated by opening contaminated envelopes was developed. Subsequent generations of contaminated envelopes originating from a single payload envelope showed a consistent two-log decrease in the number of spores transferred from one generation to the next. Opening a tertiary contaminated envelope resulted in an aerosol containing 10 3 B. anthracis spores. We developed a procedure for sampling contaminated letters by a nondestructive method aimed at providing information useful for consequence management while preserving the integrity of objects contaminated during the incident and preserving evidence for law enforcement agencies.

Histories of ear disease, otoscopic examinations, and audiologic, intelligence, and achievement tests were obtained from a cohort of 489 Alaskan Eskimo children who have been followed through the first ten years of life. Seventy-six per cent had experienced one or more episodes of otitis media since birth. Of these, 78% had their first attack during their first two years of life. Perforations and scars were present in 41%. A hearing loss of 26 decibels or greater was present in 16%, and an additional 25% were in the normal range but had a measurable air-bone gap. Children with a history of otitis media prior to 2 years of age and a hearing loss of 26 decibels or greater had a statistically significant loss of verbal ability and were behind in total reading, total math, and language. In addition, children who had an early onset of otitis media but now had normal hearing with a conductive component were also adversely affected in verbal areas. The number of otitis media episodes was related to tympanic membrane abnormalities, hearing loss, and low verbal and achievement scores. These findings indicate that otitis media has been a significant cause of morbidity in Alaskan Eskimo children, and its onset during the critical years of language development as well as the number of episodes play an important role in impairing verbal development.