Monkeypox Testing

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Last reviewed
August 13, 2022

Monkeypox Diagnostic Testing

The monkeypox virus is a viral zoonosis diagnosed by PCR test on a viral swab taken from one or more vesicles, or ulcers, says the U.K. Health Security Agency (UKHSA). For high-risk contacts of a confirmed case who have developed systemic symptoms but do not have a rash or lesions for sampling, you should take a throat swab in viral transport media, recommends the World Health Organization (WHO).

The U.S. Administration announced on June 28, 2022, that the Laboratory Response Network (LRN) had increased its testing capacity to approximately 10,000 tests per week. This LRN expansion reduces the time between symptom onset and test results, maximizing access to treatment and vaccines for patients and high-risk contacts early in the monkeypox disease. Previously, the CDC shipped monkeypox tests to Aegis Science, Labcorp, Mayo Clinic Laboratories, Quest Diagnostics, and Sonic Healthcare on June 22, 2022.

"The ability of commercial laboratories to test for monkeypox is an important pillar in our comprehensive strategy to combat this disease," commented U.S. CDC Director Rochelle Walensky, M.D., M.P.H., on July 18, 2022.  "This will increase testing capacity and make it more convenient for providers and patients to access tests by using existing provider-to-laboratory networks." 

Internationally, the Monkeypox virus Nucleic Acid Diagnostic Kit developed by Sansure Biotech obtained the C.E. certification on May 25, 2022, which means it can be distributed to E.U. countries, and Roche and its subsidiary TIB Molbiol developed LightMix® Modular Virus kits to detect the MPXV.

Monkeypox Test Method

The U.S. FDA announced on August 12, 2022, 'Given the robustness of the existing safeguards for blood safety, the FDA does not recommend those blood establishments ask donors additional, specific questions about possible exposure to monkeypox virus. Further, FDA does not recommend using laboratory diagnostic tests to screen blood donors for the monkeypox virus.'

The CDC recommends that clinicians collect two specimens for each patient, each from multiple lesions, preferably from different locations on the body and from lesions with differing appearances. The CDC Monkeypox virus testing algorithm includes non-variola Orthopoxvirus testing, and if results are positive for Orthopoxvirus, the CDC should complete further characterization testing.

Monkeypox virus PCR testing at Canadian laboratories is a nucleic acid amplification test (NAAT) that uses a real-time multiplex PCR assay to detect two targets - a generic Monkeypox virus (pan-monkeypox) target that detects both Monkeypox virus clades [West African and Congo Basin (Central African)] and a target which only detects the West African clade. And Orthopoxvirus PCR will only be used when the Monkeypox PCR assay results require further clarification.

The Monkeypox virus is part of the same family of viruses as smallpox and can be detected by diagnostic testing. On July 15, 2022: "The FDA is not aware of clinical data supporting the use of other sample types, such as blood or saliva, for monkeypox virus testing." On July 14, 2022, Eurosurveillance published a study that found the DNA of the poxvirus in semen, saliva, urine, and feces.

Monkeypox Current Procedural Terminology (CPT)

The new AMA-issued laboratory test CPT code (87593) describes molecular diagnostic testing that detects the nucleic signature of an orthopoxvirus, including the monkeypox virus.

Monkeypox Test News

August 12, 2022 - The U.S. FDA announced that 'Worldwide, there have been no reports of transmission of monkeypox virus through blood transfusion, and the risk of transfusion-transmission remains theoretical. The levels of virus in the blood of an infected or exposed individual have not been well characterized.'

August 4, 2022 - Rochelle Walensky, MD, MPH, @CDCDirector: Tweeted Monkeypox testing has significantly increased from 500 specimens tested each week in late May to nearly 8,000 specimens tested last week. Laboratories can perform 80,000 tests each week, which is much more than the current demand.

July 18, 2022 - Sonic Healthcare USA began testing for Monkeypox using the U.S. CDC Non-variola Orthopoxvirus, high complexity NAAT molecular assay in Austin, TX, and is available for providers to order through all Sonic clinical laboratories located across the USA.

July 18, 2022 - HealthTrackRx is working in a partnership with the U.S. CDC to conduct an epidemiologic study to help to understand how widespread Monkeypox is within the USA.

July 15, 2022 - The U.S. FDA recommends the use of swab samples taken directly from a lesion when testing for MPXV. The FDA is not aware of clinical data supporting the use of other sample types, such as blood or saliva, for monkeypox virus testing. 

July 11, 2022 - Mayo Clinic Laboratories began testing for monkeypox using CDC's orthopoxvirus test, which detects most non-smallpox-related orthopoxviruses, including monkeypox. Mayo Clinic Laboratories can accept specimens from anywhere in the USA and expects to be able to perform up to 10,000 tests per week.

July 8, 2022 - The U.S. CDC published a Morbidity and Mortality Weekly Report - U.S. LRN laboratories validated to perform the non-variola Orthopoxvirus (NVO) assay from May 17–June 30, 2022, testing 2,009 specimens from patients with suspected MPXV. Among these, 730 (36%) specimens from 395 patients were positive for NVO.

July 6, 2022 - Labcorp began testing for monkeypox using CDC's orthopoxvirus test (which detects all non-smallpox-related orthopoxviruses, including monkeypox).

July 1, 2022 - The Africa Centre for Disease Control (ACDC) and the African Society for Laboratory Medicine jointly held their first Real-Time PCR-based Monkeypox virus testing training for twenty African Union Member States.

June 27, 2022 - The WHO confirmed any individual meeting the definition for a suspected case should be offered to test.

June 24, 2022 - The UKHSA published guidance: Monkeypox diagnostic testing. Information on taking, submitting, and processing samples that potentially contain the monkeypox virus.

June 22, 2022 - U.S. Health and Human Services Secretary Xavier Becerra stated: "By dramatically expanding the number of testing locations throughout the country, we are making it possible for anyone who needs to be tested to do so."