Replication and Dissemination of Rift Valley Fever Virus in Culex Pipiens

Michael J. TurellDepartment of Arboviral Entomology, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland 21701

Search for other papers by Michael J. Turell in
Current site
Google Scholar
PubMed
Close
,
Thomas P. Gargan IIDepartment of Arboviral Entomology, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland 21701

Search for other papers by Thomas P. Gargan II in
Current site
Google Scholar
PubMed
Close
, and
Charles L. BaileyDepartment of Arboviral Entomology, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland 21701

Search for other papers by Charles L. Bailey in
Current site
Google Scholar
PubMed
Close
View More View Less
Restricted access

Following ingestion of 104.2 to 107.2 plaque-forming units (PFU) of Rift Valley fever (RVF) virus, 662 of 850 female Culex pipiens (78%) became infected. Those mosquitoes that became infected separated into two distinct groups: 1) those with a non-disseminated infection limited to the gut, and 2) those with a disseminated infection. The former group contained a median of 103.2 PFU, while those females with a disseminated infection contained a median of 105.5 PFU. Only those females with a disseminated infection contained a median of 105.5 PFU. Only those females with a disseminated infection were capable of transmitting virus by bite to a susceptible hamster. This is consistent with a mesenteronal escape barrier to viral dissemination. Following intrathoracic inoculation of RVF virus, all females developed a disseminated infection (26/26) and successfully transmitted virus by bite (49/49) if allowed to feed on a susceptible hamster or suckling mousc. Examination of legs and bodies separately provided a rapid and efficient method of determining dissemination status.

Save