What is the Difference Between HTLV and HIV

The key difference between HTLV and HIV is that HTLV is a retrovirus that causes diseases such as adult T-cell leukemia-lymphoma, HTLV-associated myelopathy, and hairy-cell leukemia, while HIV is a retrovirus that causes acquired immunodeficiency syndrome.

HTLV and HIV are two retroviruses that belong to the family Retroviridae. Both these retroviruses cause diseases in humans. HTLV is a distant relative of the human immunodeficiency virus (HIV). Moreover, both these retroviruses mainly infect CD⁴⁺ T lymphocytes. However, HTLV does not cause acquired immunodeficiency syndrome, while HIV does.

CONTENTS

1. Overview and Key Difference
2. What is HTLV  
3. What is HIV
4. Similarities – HTLV and HIV
5. HTLV vs. HIV in Tabular Form
6. Summary – HTLV vs. HIV

What is HTLV?

Human T-lymphotropic virus, or HTLV, was discovered in 1979. It was designated as HTLV-1. However, another strain was discovered and designated as HTLV-2. In 2005, two novel strains, HTLV-3 and HTLV-4, were discovered. But neither HTLV-3 nor HTLV-4 have been linked to human diseases. Approximately 5 to 10 million people are affected by this virus. Diseases associated with this infection are some lung diseases, certain cancers, eye inflammation, infective dermatitis, crusted scabies, and reduced immunity. People can get HTLV infection through having unprotected sex, sharing needles, and breastfeeding.

HTLV infection can be diagnosed through physical examination and using a blood test to detect antibodies to the HTLV virus. Furthermore, there is no specific treatment for HTLV-1. However, interferon alfa, IV immune globulin, and corticosteroids such as oral methylprednisolone may have some benefits against HTLV infection.

What is HIV?

Human immunodeficiency virus or HIV is a virus that attacks cells that help the body fight against the infection. This makes people more vulnerable to other infections and diseases. HIV infection can be contracted through direct contact with certain body fluids from a person with HIV infection, such as blood, semen, pre-seminal fluid, rectal fluids, vaginal fluids, and breast milk. HIV spreads through having sex, sharing needles, blood transfusion, during pregnancy, delivery, or through breastfeeding. Moreover, symptoms of HIV may include fever, chills, rash, night sweats, muscle aches, sore throat, fatigue, swollen lymph nodes, and mouth ulcers.

HIV infection can be diagnosed through physical examinations, antigen/antibody tests, antibody tests, and nucleic acid tests (NATs). Furthermore, HIV infection is treated through antiretroviral therapy using drugs such as non-nucleoside reverse transcriptase inhibitors (NNRTIs), nucleoside reverse transcriptase inhibitors (NRTIs), protease inhibitors (PIs), integrase inhibitors, and entry or fusion inhibitors.

What are the Similarities Between HTLV and HIV?

• HTLV and HIV are two different retroviruses.
• They belong to the family Retroviridae.
• Both these retroviruses cause diseases in humans.
• Both viruses mainly infect CD4+ T lymphocytes.
• They follow the same route of transmission.
• Infections caused by these viruses can be diagnosed through physical examination and blood tests.
• These infections can be treated through specific medications.

What is the Difference Between HTLV and HIV?

HTLV is a retrovirus that causes diseases such as adult T-cell leukemia-lymphoma, HTLV-associated myelopathy, and hairy-cell leukemia, while HIV is a retrovirus that causes acquired immunodeficiency syndrome. Thus, this is the key difference between HTLV and HIV. Furthermore, HTLV was discovered in 1979, whereas HIV was discovered in 1959.

The infographic below presents the differences between HTLV and HIV in tabular form for side-by-side comparison.

Summary – HTLV vs. HIV

A retrovirus is a type of virus that usually inserts a DNA copy of its RNA genome into the DNA of the host genome that it invades. HTLV and HIV are two retroviruses that belong to the family Retroviridae. Both these viruses can attack CD⁴⁺ T lymphocytes. By infecting, HTLV causes diseases such as adult T-cell leukemia-lymphoma, HTLV-associated myelopathy, and hairy cell leukemia in humans, while HIV causes acquired immunodeficiency syndrome. So, this summarizes the difference between HTLV and HIV.

Reference:

1. “HTLV-1 Infection.” Healthdirect, Healthdirect Australia.
2. “HIV/AIDS.” Mayo Clinic, Mayo Foundation for Medical Education and Research.

Image Courtesy:

1. “Phylogeny of HTLV Subtypes” By Tylercj2 – van der Kuyl 2012 BMC Retrovirology (CC BY-SA 4.0) via Commons Wikimedia
2. “HIV, the AIDS virus (yellow), infecting a human cell” By ZEISS Microscopy (CC BY-NC-ND 2.0) via Flickr