Medycyna Wet. 62 (9), 1071-1072, 2006
Bańbura M. W., Witkowski L., Chmielewska A., Tucholska A.
Mixed infections of equine herpes virus types 1 and 2 (EHV-1 and EHV-2)
110 blood samples from clinically healthy mares of English breed, half-blood and the Wielkopolska race were tested for the presence of EHV-1 and EHV-2 using nested PCR. 15 samples were EHV-1-positive, 24 samples were EHV-2-positive, whereas only 4 samples were both EHV-1 and EHV-2 positive. The virus was isolated from PBLs in equine dermal cell cultures by co-cultivation or by culture inoculation with cell lysates derived from PBLs. A total of 14 strains were isolated from EHV-2 and EHV-1/EHV-2-positive samples. However, all of them were identified by nPCR as being type 2. Since no EHV-1 was isolated, even from dually infected leukocytes, it was concluded that the presence of EHV-2 does not stimulate in-vitro isolation of EHV-1 from infected leukocytes. It is tempting to speculate that such stimulatory effects in-vivo may involve EHV-2-induced immunosupression. Despite any possible mechanism of EHV-1 stimulation, it seems that EHV-2 does not play a significant role in the epidemiology of EHV-1-caused miscarriages in horses since mixed infections are rather rare.
Keywords: EHV-1, EHV-2, virus