May 28, 2019
Dear Colleague,
Because mosquitoes are most active in Virginia between May and October, I am providing updates to assist you in diagnosing and treating arboviral infections:
Mosquito-borne Infections
• West Nile virus is the leading cause of locally-acquired, mosquito-borne infection in Virginia. In 2018, a record number of infections (48), including 9 deaths, were reported.
• Based on cases identified in neighboring states with similar vector ecology, La Crosse virus (LACV) or “California encephalitis virus” may be under-recognized and under-reported in Virginia. Patients suspected of having LACV infections can be tested through Virginia’s state public health laboratory, the Division of Consolidated Laboratory Services. Contact your local health department to request testing.
• Updated recommendations for Zika virus testing are available on the VDH website.
• IV quinidine for the treatment of severe malaria is no longer commercially available. IV artesunate has become the first-line drug in the United States; CDC is providing it under an expanded access investigational drug protocol.
Tick-borne Infections
• Rocky Mountain spotted fever (RMSF) may be over-diagnosed in Virginia. RMSF diagnostic tests can react to non-pathogenic spotted fever group agents carried by Lone star ticks, the most common cause of tick bites in Virginia. VDH recommends that healthcare providers consider ehrlichiosis in differential diagnoses that include RMSF and consider testing patients by a multiplex PCR assay that includes Ehrlichia/Anaplasma.
• Testing for emerging viruses (e.g. Powassan and Heartland viruses) at CDC may be facilitated by Virginia’s state public health laboratory, the Division of Consolidated Laboratory Services. Contact your local health department to request testing.
Public Health Actions for Healthcare Providers
• Remind patients to take steps to minimize tick and mosquito bites.
• For people traveling abroad, destination-specific recommendations are available on CDC’s Travelers’ Health website.
• A resource to assist in distinguishing arboviral infections and recommendations for testing is available on VDH’s website.
• Detailed information about the diagnosis and treatment of arboviral infections is available on CDC’s website.
• If you have additional questions, please contact your local health department.
Please contact Dr. David Gaines, State Public Health Entomologist, at david.gaines@vdh.virginia.gov for additional information.
Sincerely,
M. Norman Oliver, MD, MA
State Health Commissioner