Accession Number : AD0700088

Title :   STUDY OF ABILITY OF HAEMAPHYSALIS JAPONICA DOUGLASI NUTT. AND WARB. AND HAEMAPHYSALIS NEUMANNI D. TO ASSIMILATE RICKETTSIAE UNDER EXPERIMENTAL CONDITIONS,

Corporate Author : NAVAL MEDICAL RESEARCH UNIT NO 3 CAIRO (EGYPT) DEPT OF MEDICAL ZOOLOGY

Personal Author(s) : Belikova,N. P. ; Somov,G. P.

Report Date : 1969

Pagination or Media Count : 4

Abstract : The natural infection of Haemaphysalis japonica douglasi N.W. with the agent of tickborne rickettsiosis in Primor'ye region was demonstrated. Experiments were designed to determine rickettsial absorption by ticks during a bloodmeal, the transmission of rickettsiae during metamorphosis, and the ability of subsequent generations to cause infection in susceptible animals. Verification of the ability of H. japonica douglasi and H. neumanni to assimilate rickettsiae at various periods of bloodsucking was made by means of intraperitoneal infection of guinea pigs with a suspension from engorged ticks. Experiments showed that H. japonica douglasi are able to assimilate the agent of tickborne rickettsiosis during a bloodmeal and to transmit it during the metamorphosis process to the next generations. These data allowed us to conclude that H. japonica douglasi participates in the circulation of tickborne rickettsiosis agent in Primor'ye region and should be considered as a vector of this infection. Most H. neumanni females that fed on infected guinea pigs did not reach the necessary degree of engorgement and died without ovipositing, or produced a small number of larvae. Adults of this tick species slightly assimilate rickettsiae during bloodsucking on infected guinea pigs. Nymphs are able in a small degree to assimilate rickettsiae during bloodsucking and to accumulate them in their body. In 5 tests, we were able only once to reveal rickettsiae in engorged nymphs. Thus, we were unable to prove the presence of transstadial and transovarial transmission of Dermacentroxenus sibericus rickettsiae in H. neumanni.

Descriptors :   (*TICKS, *RICKETTSIA), DISEASE VECTORS, PARASITES, INFECTIONS, LIFE CYCLES, LARVAE, NYMPH, GUINEA PIGS, USSR

Subject Categories : Microbiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE