Development and persistence of antibodies to Orientia tsutsugamushi in the roof rat, Rattus rattus and laboratory mice following attachment of naturally infected Leptotrombidium deliense

• Published in: Acta tropica 2000-12, Vol.77 (3), p.279-285
• Main Authors: Frances, S.P., Watcharapichat, Pochaman, Phulsuksombati, Duangporn
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Bacterial - analysis; Antibody development; Bacterial diseases; Biological and medical sciences; Female; Human bacterial diseases; Infectious diseases; Laboratory mice; Leptotrombidium deliense; Male; Medical sciences; Mice; Mice, Inbred ICR; Muridae; Orientia tsutsugamushi; Orientia tsutsugamushi - immunology; Rats; Rattus rattus; Rickettsial diseases; Scrub typhus; Scrub Typhus - transmission; Trombiculidae - microbiology; Tropical bacterial diseases; Tropical medicine
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/S0001-706X(00)00144-3

The development and persistence of antibodies to Orientia tsutsugamushi in Rattus rattus and laboratory mice following infection from the bite of naturally infected Leptotrombidium deliense is reported. Antibodies in R. rattus were first detected using an indirect immunoperoxidase method 2 weeks after attachment of an infected mite. The IgM antibody response was mild, and was detected 2, 4 and 6 weeks after infection, while the IgG response was stronger and was detected from 2 to 19 weeks after infection, when the tests ceased. Active rickettsiae were isolated from R. rattus 1–8 weeks after attachment of infected L. deliense, but rats were not adversely affected by infection and appeared to behave in the same way as uninfected rats. In contrast to rats, laboratory mice were killed by O. tsutsugamushi following infection by attachment of infected L. deliense. The development of antibodies in mice was not detected before gross symptoms of infection were observed. Antibodies were first detected 14 days after attachment of infected mites, when mice were close to death.