Heartland Virus Epidemiology, Vector Association, and Disease Potential

Details

• Alternative Title:
  Viruses
• Personal Author:
  Brault, Aaron C. ; Savage, Harry M. ; Duggal, Nisha K. ; Eisen, Rebecca J. ; Staples, J. Erin
• Description:
  First identified in two Missouri farmers exhibiting low white-blood-cell and platelet counts in 2009, Heartland virus (HRTV) is genetically closely related to severe fever with thrombocytopenia syndrome virus (SFTSV), a tick-borne phlebovirus producing similar symptoms in China, Korea, and Japan. Field isolations of HRTV from several life stages of unfed, host-seeking |, the lone star tick, implicated it as a putative vector capable of transstadial transmission. Laboratory vector competence assessments confirmed transstadial transmission of HRTV, demonstrated vertical infection, and showed co-feeding infection between |. A vertical infection rate of 33% from adult females to larvae in the laboratory was observed, while only one of 386 pools of molted nymphs (1930) reared from co-feeding larvae was positive for HRTV (maximum-likelihood estimate of infection rate = 0.52/1000). Over 35 human HRTV cases, all within the distribution range of |, have been documented. Serological testing of wildlife in areas near the index human cases, as well as in widely separated regions of the eastern United States where | occur, indicated many potential hosts such as raccoons and white-tailed deer. Attempts, however, to experimentally infect mice, rabbits, hamsters, chickens, raccoons, goats, and deer failed to produce detectable viremia. Immune-compromised mice and hamsters are the only susceptible models. Vertical infection augmented by co-feeding transmission could play a role in maintaining the virus in nature. A more complete assessment of the natural transmission cycle of HRTV coupled with serosurveys and enhanced HRTV disease surveillance are needed to better understand transmission dynamics and human health risks.
• Subjects:
  Amblyomma Americanum Heartland Virus Lone Star Tick Review Thrombocytopenia Transmission
• Source:
  Viruses. 2018; 10(9).
• Pubmed ID:
  30223439
• Pubmed Central ID:
  PMC6164824
• Document Type:
  Journal Article
• Volume:
  10
• Issue:
  9
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:9aac6d0f3be72fbfde93478c24c5a0b7ddf231160bf86d4fc01cf282a52d6d72
• Download URL:
  https://stacks.cdc.gov/view/cdc/60063/cdc_60063_DS1.pdf
• File Type:
  [PDF - 1.12 MB ]