False-positive HIV tests don’t imply that a person is immunodeficient, contrary to claim by Peter McCullough

Key takeaway

Immunodeficiency is broadly defined as a state in which a person’s immune system is unable to fight off infections and cancer. It can arise as a result of genetic conditions, infection, or other environmental factors. One form of immunodeficiency, called acquired immunodeficiency syndrome (AIDS), is caused by untreated HIV infection. HIV detection tests are highly specific, meaning most positive test results are truly positive. Rarely, infections by other pathogens and underlying health conditions can cause false-positive results in HIV tests, but this doesn’t indicate immunodeficiency. COVID-19 vaccines don’t cause false-positive HIV tests nor do they cause immunodeficiency.

Reviewed content

Verdict:

Flawed reasoning

Claim:

“The HIV test can turn positive after COVID-19 as well as the vaccine”; “maybe a form of immunodeficiency is there”

Verdict detail

Inadequate support: There is no scientific evidence that COVID-19 vaccines cause false-positive HIV tests.
Flawed Reasoning: The claim implies that a false-positive HIV test is a sign of an immunodeficiency. This is illogical because the test is designed to detect signs of an HIV infection, not immunodeficiency. Immunodeficiency can develop from an untreated HIV infection but is detected through other tests, not a HIV test.

See our method of evaluation

Full Claim

“Nine studies are reporting false positive HIV tests”; “The HIV test can turn positive after COVID-19 as well as the vaccine”; “It’s not AIDS because the virus is not there” “maybe a form of immunodeficiency is there”

The goal of vaccines is to strengthen one’s immunity against a specific disease. It’s because of the immunity-boosting effect of vaccines that several deadly infectious diseases have disappeared or are on the verge of eradication.

Yet, during the COVID-19 pandemic, false claims have spread suggesting that COVID-19 vaccines weakened people’s immune systems. Over the past couple of years, Health Feedback has explained that COVID-19 vaccines don’t increase the risk of disease nor cause immunodeficiency.

Nevertheless, cardiologist Peter McCullough has continued to push this narrative. In January 2024 McCullough claimed during an interview on the Shannon Joy Show that “The HIV test can turn positive after COVID-19 as well as the [COVID-19] vaccine”.

Although McCullough acknowledged that such a positive result would be a false-positive because “the [HIV] virus is not there” and that it’s therefore “not AIDS”, he maintained that a positive HIV test could indicate that “maybe a form of immunodeficiency is there”. He referred to this alleged condition as “vaccine-induced immunodeficiency (VAIDS)”.

However, this is simply a repetition of an already debunked claim that has been around since at least 2021, as reported by fact-checking organization Africa Check. We explain below why the claim is baseless.

No evidence of false-positive HIV tests caused by COVID-19 vaccination

We didn’t find any scientific evidence of false-positive Human Immunodeficiency Virus (HIV) detection tests caused by COVID-19 vaccination that could support McCullough’s claim. A search on PubMed^#, a repository of biomedical publications hosted by the U.S. National Library of Medicine, retrieved no results.

Studies have identified an increased risk of false-positive HIV tests among patients with acute COVID-19^[1-3] although the cause of these false positives is unclear.

Modern HIV tests, also known as fourth-generation tests, detect antibodies against HIV in the blood as well as HIV antigens, namely the HIV protein p24. The combination of antibody and antigen testing allows for the detection of infection as early as fourteen days after exposure to the virus.

Indeed, the findings of some studies suggest that some similarities between SARS-CoV-2 antigens and HIV antigens^[2] or cross-reactivity between antibodies against SARS-CoV-2 and antibodies against HIV could explain the false-positive HIV tests among COVID-19 patients^[3]. However, no clear evidence is available so far.

There is one record of a COVID-19 vaccine candidate that might interfere with HIV tests. However, its development was stopped and it was never distributed to the public. As Health Feedback explained, the University of Queensland, Australia, began the development of a COVID-19 vaccine that includes a small fragment of a HIV protein. This fragment isn’t able to cause any type of HIV-associated health conditions. However, authorities decided to stop the development after the Phase I clinical trial owing to concerns that the HIV protein fragment could elicit the production of antibodies in the body that would then cause false-positive HIV tests.

In summary, there are no records of false-positive HIV tests among people from the public vaccinated against COVID-19, contradicting the claim.

A false-positive HIV test alone cannot indicate an immunodeficiency

Immunodeficiency is broadly defined as a state in which a person’s immune system is unable to fight off infections and cancer. It can arise as a result of genetic conditions, infection, or other environmental factors.

Simple logical reasoning shows us that false-positive HIV tests cannot be taken as a sign of immunodeficiency.

First, we explained above that a HIV test detects the presence of the virus HIV, not an immunodeficiency. HIV infection can lead to immunodeficiency if left untreated. This is because HIV targets and destroys specific white blood cells called CD4 T lymphocytes, thus weakening one’s immune system.

In order to diagnose a person with acquired immunodeficiency syndrome (AIDS), clinicians need to count the number of those CD4 cells. A healthy individual has between 500 to 1,500 CD4 cells per microliter of blood (a microliter is a millionth of a liter). When the CD4 cell count of an HIV-positive individual drops below 200 cells per microliter of blood, the patient is diagnosed with AIDS.

Thus, the result of an HIV test only tells us that the virus is there—provided that it is a true-positive result— but it won’t tell us if CD4 T cells have fallen sufficiently to create a state of immunodeficiency. Therefore, it’s not possible to jump to conclusions on the sole basis of an HIV test result, contrary to what McCullough did.

Second, it is clear from what we explained above that this acquired immunodeficiency is the consequence of the action of HIV in the body. As McCullough himself acknowledged, a false-positive test means that there’s actually no HIV virus in the person. In other words, the infectious agent responsible for killing CD4 T lymphocytes isn’t there. Therefore, it cannot cause an immunodeficiency.

COVID-19 vaccines don’t weaken the immune system

Experts in immunology, infectious diseases, and vaccines told Reuters and the Associated Press that the concept of VAIDS used by McCullough has no scientific meaning. This is in fact a baseless term coined to establish an apparent similarity between an alleged vaccine-induced immunodeficiency and the well-known disease AIDS. However, VAIDS simply doesn’t exist.

Health Feedback refuted similar claims on multiple occasions. Most of these claims relied on miscalculations of the number of COVID-19 cases among vaccinated individuals compared to unvaccinated ones or incorrectly equating the COVID-19 vaccine’s effectiveness with the strength of one’s immune system. In fact, there’s no indication that COVID-19 vaccines weaken the recipient’s immunity.

McCullough also cited a study performed by researchers at the Cleveland Clinic as supporting evidence of this claim^[4]. However, Health Feedback explained in detail in a previous review that this misinterprets the study. The study wasn’t designed to assess the effect of a growing number of vaccine doses on the risk of getting COVID-19. Consequently, many possible biases, such as a potential correlation between the number of doses received and difference in the risk of exposure to the virus, weren’t taken into account.

Contradicting McCullough’s interpretation of the results, the study’s corresponding author told Health Feedback, “Any claim that our study shows a causal relationship between getting more doses of the COVID-19 vaccine and higher risk of infection is false”.

NOTE:

# Pubmed query: (false-positive[Title] OR positive[Title])) AND COVID-19[Title] AND vaccin*[Title] AND (HIV[Title] OR AIDS[Title] OR immunodeficiency[Title])

REFERENCES

• 1 – Alfie et al. (2023) Increased risk of false-positive HIV ELISA results after COVID-19. AIDS.
• 2 – Gudipati et al. (2023) Increase in False-Positive Fourth-Generation Human Immunodeficiency Virus Tests in Patients With Coronavirus Disease 2019. Clinical Infectious Diseases.
• 3 – Elsner et al. (2023) False-Positive Screening and Confirmatory HIV Diagnostic Test in a Patient with Cured SARS-CoV-2 Infection Is Not Mediated by Env/Spike Cross-Reactive Antibodies. Viruses.
• 4 – Shrestha et al. (2023) Effectiveness of the Coronavirus Disease 2019 Bivalent Vaccine. Open Forum Infectious Diseases.