Description

Vector borne illnesses are caused by infectious agents (eg, bacteria, protozoa and viruses) that are transmitted to animals and humans by carriers (vectors) such as fleas, lice (body), mosquitoes, sand flies or ticks. Multiple laboratory testing options exist for the diagnosis of vector borne illness, including culture, microscopy, molecular-based methods and serology. Molecular based tests amplify pieces of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) so that infection can be detected using a specialized test. The established diagnostic approach varies by the specific symptoms and stage of illness at the time of testing.

A bite from an infected tick is the leading cause of vector borne illness in the United States (US). According to the Centers for Disease Control and Prevention (CDC), at least 18 tickborne pathogens have currently been identified and a tick may harbor and transmit more than one pathogen at a time. An individual that is exposed to an infected tick bite will commonly experience symptoms such as body aches, fatigue, fever, joint pain or rashes. Tickborne transmission is most common in particular regions and during certain seasons in the US.

Anaplasmosis

Also known as human granulocytic anaplasmosis (HGA), is a tickborne disease caused by the bacterium Anaplasma phagocytophilum. The bacteria are carried by the Ixodes scapularis (black-legged or deer tick) in the Northeast and Midwestern US and the Ixodes pacificus (western black-legged tick) along the West Coast, with peak transmission between June and November. Human monocytic ehrlichiosis (HME) is a tickborne illness that is similar in clinical presentation to HGA and is caused by the bacterium Ehrlichia chaffeensis. HME is endemic in the southeastern, south-central, and mid-Atlantic regions of the US and is carried by Amblyomma americanum (lone star tick). Polymerase chain reaction (PCR) testing, a blood smear and serology are all recommended options for testing in endemic areas where an individual presents with the typical febrile illness and outdoor exposure.

Babesiosis

Is caused by microscopic parasites of the genus Babesia. More than 100 species have been reported, but most human cases of Babesia infection in the US are caused by the parasite Babesia microti. Transmission is initiated by the bite of an infected black-legged or deer tick and mainly occurs in parts of the Northeast and upper Midwest, which usually peaks during the warmer months. Diagnosis of active babesiosis is confirmed by visualizing Babesia parasites on light-microscopic examination of a peripheral blood smear and/or PCR assays that detect Babesia microti DNA in whole blood samples.

Bartonellosis

Is the term used to describe any infectious illness caused by bacteria belonging to the Bartonella genus. Bartonella includes at least 22 named species of bacteria that are mainly transmitted by carriers (vectors), including fleas, lice or sandflies. Both domestic and wild animals can be infected with Bartonella species. The 3 most common Bartonella species known to cause illness in humans are Bartonella bacilliformis (Carrion's disease), Bartonella henselae (cat scratch disease) and Bartonella quintana (trench fever). Bartonellosis can cause a wide range of symptoms varying from mild to severe and may be worse in an individual with an immunocompromised condition (eg, cancer, chronic organ disease, HIV/AIDS).

There are currently no tests available for Bartonella species that are cleared by the US Food and Drug Administration (FDA).

Diagnosis is most often made by assessing the individual’s symptoms and exposure risk along with indirect fluorescence assay (IFA) antibody testing for the suspected pathogen if indicated. An amplified PCR test with a proprietary sample enrichment step called Bartonella Digital ePCR has been proposed to detect a broad range of Bartonella species. (Refer to Coverage Limitations section)

Lyme disease

Is caused by the bacterium Borrelia burgdorferi and less commonly, Borrelia mayonii. It is also transmitted through the bite of an infected black-legged or deer tick and is the most common tickborne illness in the US. Typical symptoms include a characteristic skin rash called erythema migrans, fatigue, fever and headache. If left untreated, infection can spread to the heart, joints and nervous system.

Lyme disease is typically diagnosed based on symptoms, physical findings and the possible exposure to infected ticks. The standard laboratory test used is a two-tiered, serology antibody testing using a sensitive enzyme immunoassay or an immunofluorescence antibody; followed by a Western blot test. Other tests that have been proposed to diagnose Lyme disease include IgG and IgM ImmunoBlot testing, nucleic acid (DNA or RNA) amplified or direct probe testing and a urine-based test to detect the outer surface protein A (OspA) which can be found on Borrelia burgdorferi. (Refer to Coverage Limitations section)

Relapsing fever

Is a bacterial infection that can cause recurring bouts of fever, headache, joint and muscle aches and nausea. The 2 most common types of relapsing fever illness in the US are tick borne relapsing fever (TBRF), usually caused by the Borrelia hermsii or Borrelia turicatae species. The bacteria associated with TBRF are spirochete (long and spiral-shaped) and can be seen with microscopy. IgG and IgM ImmunoBlot testing has also been proposed to detect TBRF Borrelia antigens. (Refer to Coverage Limitations section)

Borrelia miyamotoi (hard tick relapsing fever)

Is a type of spiral-shaped bacteria that is closely related to the bacteria that cause TBRF. It occurs in the same regions where Lyme disease is found and is also transmitted by the black-legged or deer tick. A PCR assay that detects Borrelia miyamotoi DNA in blood is the preferred method for diagnosis.

For information regarding molecular diagnostic testing for pathogens other than those associated with Lyme Disease or other vector borne illness, please refer to Molecular Diagnostic Testing for Reproductive Health and Multiplex Pathogen Testing.

Coverage Determination

Humana members may be eligible under the Plan for PCR testing for vector borne illness when the following criteria are met:

• Confirmatory diagnosis of infection when clinical symptoms (eg, body aches, fatigue, fever, joint pain, rash) and exposure are present for the following indications:
  1. Anaplasmosis (HGA) (Anaplasma phagocytophilum) (87468)
  2. Babesiosis (eg, Babesia microti) (87469)
  3. Hard tick relapsing fever (Borrelia miyamotoi) (87478)
  4. Human monocytic ehrlichiosis (HME) (Ehrlichia chaffeensis) (87484)

Coverage Limitations

Humana members may NOT be eligible under the Plan for multipathogen panels unless ALL pathogens being tested in the panel meet the criteria above.

Humana members may NOT be eligible under the Plan for molecular diagnostic testing for Bartonella or Borrelia species including, but may not be limited to:

• Bartonella digital ePCR (0302U)
• Bartonella droplet digital PCR (0301U)
• Borrelia burgdorferi nucleic acid (DNA or RNA) amplified probe (87476)
• Borrelia burgdorferi nucleic acid (DNA or RNA) direct probe (87475)
• Lyme Borrelia Nanotrap Antigen Test (0316U)
• Lyme ImmunoBlot IgG (0042U)
• Lyme ImmunoBlot IgM (0041U)
• TBRF ImmunoBlot IgG (0044U)
• TBRF ImmunoBlot IgM (0043U)

These are considered experimental/investigational as they are not identified as widely used and generally accepted for the proposed uses as reported in nationally recognized peer-reviewed medical literature published in the English language.

Molecular Diagnostic Testing for Lyme Disease and Other Vector Borne Illness Effective Date: 03/23/2023 Revision Date: 03/23/2023 Review Date: 03/23/2023 Policy Number: HUM-0609-003 Page: 5 of 10

Humana's documents are updated regularly online. When printed, the version of this document becomes uncontrolled. Do not rely on printed copies for the most up-to-date version. Refer to Medical and Pharmacy Coverage Policies to verify that this is the current version before utilizing.

Additional Information about Lyme Disease and Other Tickborne Illness

Background

• Centers for Disease Control (CDC) and Prevention
• National Library of Medicine

Medical Alternatives

Alternatives to Bartonella Digital ePCR testing for Bartonellosis include, but may not be limited to:

• Indirect fluorescence assay (IFA) antibody testing
• Physical exam for typical signs and symptoms along with an exposure history

Alternatives to IgG and IgM ImmunoBlot testing and urine detection of OspA for Lyme disease include, but may not be limited to:

• Two-tiered, serology antibody testing using a sensitive enzyme immunoassay (EIA) or immunofluorescence antibody; followed by a Western blot or second EIA test

Alternatives to IgG and IgM ImmunoBlot testing for TBRF include, but may not be limited to:

• Direct visualization with microscopy to identify spirochetes in a blood or tissue specimen

Physician consultation is advised to make an informed decision based on an individual’s health needs.

Humana may offer a disease management program for this condition. The member may call the number on his/her identification card to ask about our programs to help manage his/her care.