Volume 13, Number 6—June 2007
Research
West Nile Virus Viremia in Eastern Chipmunks (Tamias striatus) Sufficient for Infecting Different Mosquitoes
Table 1
Histologic lesions observed in eastern chipmunks (Tamias striatus) after intramuscular inoculation with West Nile virus (WNV)
Chipmunk no. | Experiment no. | WNV dose* | Day of death† | Microscopic lesions‡/WNV antigen§¶ |
||||
---|---|---|---|---|---|---|---|---|
Brain | Liver | Spleen | Kidney | Small intestine | ||||
1 | 1 | 5.7 | 11 (E) | −/− | −/− | −/− | −/− | −/− |
2 | 2 | 3.5 | 2 (S) | −/− | −/− | −/− | −/− | −/− |
3 | 2 | 3.5 | 11 (E) | ++/+++ | +/− | −/− | +/+ | −/− |
4 | 2 | 3.5 | 4 (S) | −/− | +/++ | –/+ | –/+ | –/+ |
5 | 2 | 1.5 | 27 (U) | −/− | −/− | −/− | −/− | −/− |
6 | 2 | 1.5 | 1 (S) | −/− | −/− | −/− | −/− | −/− |
7 | 2 | 1.5 | 14 (E) | −/− | −/− | −/− | –/+ | −/− |
8 | 3 | 2.6 | 9 (E) | ++/++ | +/++ | −/− | +/++ | –/++ |
*Log10 PFU of WNV.
†Day of death, day postinoculation that death occurred by euthanasia (E) if a chipmunk had symptoms that prevented it from ambulating to or consuming water or food; S, death associated with sampling; U, cause of death not determined.
‡By histologic examination, lesions were not present (–), mild (+), moderate (++), or severe (+++).
§By histologic examination, WNV antigen was absent (–), mild (+), moderate (++), or extensive (+++).
¶Organs with no detectable lesions or WNV antigen included heart, lung, adrenal and salivary glands, large intestine, pancreas, and urinary bladder.