Accession Number:

ADA155593

Title:

Transmission, Control and Treatment of Infectious Diseases of Military Importance in Equatorial Asia.

Descriptive Note:

Annual rept. Jan-Aug 82,

Corporate Author:

INSTITUTE FOR MEDICAL RESEARCH KUALA LUMPUR (MALAYSIA)

Personal Author(s):

Report Date:

1982-09-01

Pagination or Media Count:

31.0

Abstract:

The plaquing and cloning procedures have been established and studies requiring cloning are underway. Preliminary results of characterizations indicate that the Karp and Karp-related strains are most prevalent in the endemic region. The electron microscopy study of infected endothelial cells is nearing completion micrographs are being examinedinterpreted. Cell mediated immunity studies suggest that immunity to scrub typhus can be predicted using the lymphocyte transformation assay, although this will require confirmation by proposed studies. The stability of the avirulence characteristics of several R.tsutsugamushi strains has been demonstrated by testing after 25 continuous passages in mice or cultured cells. Vector transmission studies have shown that infection does not appear to influence the sex ratio of infected siblings, that mites are not infected by feeding on infected mite eggs, and the minimum attachment time for vector chiggers tested varies from 3 12 to 9 hours. Also, chromosome studies have shown that the diploid number of chromosomes in different species of vector mites is not the same. Work with the latex agglutination technique as an early diagnostic tool continues, and current work centers around testing for use with human serum specimens. The reinfection study using volunteers who had received chemoprophylaxis during our previous doxycycline trial was very successful, 7 of the 8 resisting the challenge by infected chiggers.

Subject Categories:

  • Medicine and Medical Research

Distribution Statement:

APPROVED FOR PUBLIC RELEASE