Heartland Virus

Heartland virus is a bunyavirus. The genus bandavirus consists of nine tickborne bunyaviruses, with four known to cause disease in humans: Dabie bandavirus, also known as severe fever with thrombocytopenia syndrome virus, Banja bandavirus, Guertu virus and Heartland virus.

Heartland virus was first isolated from two northwestern Missouri farmers in 2009. They were hospitalized with fever, leukopenia, and thrombocytopenia. A total of 6 cases were confirmed during 2012–2013. Five patients were Missouri residents and one was a Tennessee resident. Four of these patients were hospitalized and one died. A seroprevalence study in 2013 fournd that 0.9% of Missouri blood donors tested positive for antibodies to Heartland virus. Given Missouri’s population of 6.043 million, this equated to an estimated 543,870 cases. Only 60 human cases of Heartland virus infection have been reported in 13 states. 

Several species of wildlife have formed antibodies against Heartland virus. Seropositivity has been found in white-tailed deer, coyotes, raccoons, moose, Virginia opossums, and horses. 

Heartland virus is believed to be transmitted through infected ticks or other arthropods. In a recent study, 56,428 ticks were collected in northwest Missouri for analysis. Lone Star ticks (Amblyomma americanum) were the most common species identified and nymph stage Lone Star ticks were found to harbor the Heartland virus.

Patients infected with Heartland virus typically present with fever, leukopenia and thrombocytopenia. Nonspecific findings include fatigue, anorexia, headache, nausea, myalgia, or arthralgia. These findings mimic the signs and symptoms of Ehrlichia and Anaplasma infection which need to be ruled out. Unlike these infections, patients with Heartland virus do not respond to doxycycline therapy. No vaccine or medication is available to prevent or treat Heartland virus disease.

Heartland virus can be detected in plasma and cerebrospinal fluid by real-time reverse transcription polymerase chain reaction (RT-PCR). The presence of HRTV RNA in a specimen can be used to support the diagnosis of acute HRTV infection

References

(Pastula DM, etal. Notes from the Field: Heartland Virus Disease — United States, 2012–2013, MMWR Weekly, March 28, 2014 / 63(12);270-271).

Savage HM, Godsey MS Jr, Lambert A, et al. First detection of heartland virus (Bunyaviridae: Phlebovirus) from field collected arthropods. Am J Trop Med Hyg 2013;89:445–52).

Dembek ZF, et al, Heartland Virus Disease-An Underreported Emerging Infection. Microorganisms. 2024 Jan 29;12(2):286.