Bourbon Virus

As summer arrives, so do the ticks

Bourbon is a virus that is brand new to doctors. It’s another reason to avoid ticks. It's also a reminder there are lots of infections out there that can emerge and cause disease in people - whether far away or in Kansas.

What happened was: In Kansas in 2014, doctors were stumped. A patient was getting sicker. Fever and rash seemed to point to certain infections but all the tests were negative. The CDC was brought in and a new virus was identified – Bourbon virus.

A later case was identified in Oklahoma in May 2015. Because the virus has not been identified in a large number of people, there’s much still to be learned about the virus.

How do we know about it?

An otherwise healthy man in Kansas, aged 50, developed a new illness in 2014. He had a fever, nausea, vomiting, loss of appetite, fatigue, and a rash. Lab tests showed he had low white cells and low platelets. He was known to have had tick bites. This illness seemed a lot like other tick-borne diseases (especially ehrlichiosis). So he was given doxycycline, an antibiotic that treats other tickborne diseases that are often caused by bacteria that respond to doxycycline. He did not improve with the antibiotic. He died.

Without other cases, it is unclear how dangerous the virus is. The one death may have been related to other factors.

His labs tested negative. Further testing  - through the CDC (Center for Disease Control in the US) as well as through local Kansas laboratories - identified a new virus.

The later patient in May 2015 survived.

Why is it called Bourbon virus?

The first case was identified in Bourbon County, Kansas in the US.

Is it found in ticks?

We don't know the distribution of the virus. It is a virus that is similar to others found in ticks elsewhere. The patient who had the disease had tick bite exposures.

However, there is much we do not know about this disease.

What are the symptoms?

It has only been identified in one person. Symptoms may be different in different people. Symptoms appear to include: Fever, Fatigue, Rash, Nausea, Vomiting, Loss of appetite.

What is the treatment?

There is no treatment other than supportive care - that we know of yet. This means giving IV fluids,  nutrition, and intensive nursing care. In serious cases, this may include assisting with breathing through ventilation or kidney function through dialysis.

Antibiotics won’t work because this is a virus. There are no antivirals or vaccines

How to avoid ticks:

Avoid areas with high grasses, bushes, and wooded areas

When in these potential tick areas:

  • Use insect repellent with DEET
  • Wear clothing with long sleeves and pants; pull socks over pant legs
  • Use permethrin on clothing

Immediately after visiting tick areas:

  • Do a full-body tick check – especially through bathing/showering
  • Check pets and any gear for ticks

How is it identified?

There isn’t a test available for most clinicians. However, the CDC has been able to identify the virus through a blood test. Referrals of similar cases could be identified at the CDC.

What other diseases transmitted by ticks?

There are actually a lot of infections that can cause disease from a tick bite.

  • Lyme Disease which is the most commonly known and spread by Ixodes scapularis in the Northeast US and Upper Midwest US and Ixodes pacificus along Pacific Coast.
  • Ehrlichiosis - Ehrlichia chaffeensis and Ehrlichia ewingii - spread by the Lonestar tick and Anaplasmosis - Anaplasma phagocytophilum (previously human granulocytic ehrlichiosis) spread by Ixodes scapularis and Ixodes pacificus)
  • Rocky Mountain Spotted Fever, a dangerous disease, spread by the American dog tick (Dermacentor variabilis), Rocky Mountain wood tick (Dermacentor andersoni), and the brown dog tick (Rhipicephalus sangunineus)
  • Tularemia, a rare but dangerous disease, spread by the dog tick (Dermacentor variabilis), the wood tick (Dermacentor andersoni), and the lone star tick (Amblyomma americanum).
  • Babesia caused by Babesia microti from the Ixodes scapularis tick.
  • Heartland virus disease, which is also a relatively new disease, found in Missouri and Tennessee, and likely spread through Lonestar Ticks.
  • Borrelia miyamotoi spread by Ixodes scapularis much like Lyme disease.
  • Colorado tick fever in the Rocky Mountains by the Rocky Mountain wood tick (Dermacentor andersoni).
  • There are also many other diseases - Powassan disease in the northeast and Great Lakes, STARI (Southern tick-associated rash illness), Rickettsia parker, Tickborne relapsing fever, 364D rickettsiosis, and others. 

What sort of virus is it?

It’s an RNA virus in the Orthomyxoviridae family (genus Thogotovirus). The Orthomyxoviruses we know; these include the influenza viruses. The Thogotoviruses are less common but are found worldwide. The Thogotoviruses are arboviruses, spread by arthropods, like ticks. There are types that do cause disease in humans.  Thogoto virus (THOV) and Dhori virus (DHOV), which have been found in Kenya (Thogoto Forest) and India, respectively. 

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