Skip to Main Content

Infectious disease specialists are growing increasingly concerned by the U.S. strategy for testing for monkeypox, warning that it’s creating a bottleneck and squandering the limited time the country may have to get the outbreak under control.

Under the current system, specimens must be sent to one of 74 laboratories across the country before being sent to the Centers for Disease Control and Prevention. Experts who spoke with STAT argue the United States should be testing more broadly for monkeypox, allowing more labs to become part of the process.


“Every single day that we’re not fixing the testing bottleneck, every single day that we’re not getting on top of getting the information out to the networks that need to be aware of this, is time that we are losing in terms of that window closing on containment,” said Boghuma Titanji, an assistant professor of infectious diseases at Emory University.

Titanji, who in her native Cameroon was involved in a monkeypox outbreak investigation, said the U.S. case count — markedly lower than other similar countries — is almost certainly an underestimate of how much transmission is actually happening here. The United Kingdom announced Monday that it has now detected 302 cases. Canada reported 77 cases as of last Friday. 

“The U.S. probably has as many cases as Canada or the U.K.,” she said. “We’re just not testing enough to be able to reliably say that there are only 25 cases. I think we need to be testing way more than we’re doing,” she said. After STAT spoke with Titanji the CDC updated the monkeypox case count from 25 to 31 cases; 13 states have detected cases. 


Jennifer Nuzzo, director of Brown University’s new Center for Pandemic Preparedness and Response, said the current system makes sense for a smaller outbreak, but doesn’t suit the needs of clinicians who should be actively looking for monkeypox infections.

“This two-step process is not going to scale,” she said in an interview. “This is a cumbersome process. When you have something that’s spreading in ways that we’re not able to see — in the sense that we’re finding cases without known contacts or known links of transmission — it really feels like we’re in a different mode of the response.” 

STAT reached out to the CDC to ask if it was considering changing the testing protocol, but did not receive a reply as of the time of this publication. In late May the agency said it was weighing what it would take to expand testing capacity to other laboratories.  

The unprecedented multi-country outbreak came to global attention in mid-May, when the U.K. announced it had discovered four cases of monkeypox among men who had not traveled to the countries in West and Central Africa where the virus is endemic in nature. Since then, roughly 40 countries have detected upwards of 1,000 monkeypox infections, with the vast majority of cases in men who identify as gay, bisexual, or as men who have sex with men.

Emerging reports from national public health agencies have revealed that some of the cases do not follow the patterns of illness described in the medical literature. Some develop the monkeypox rash before they experience systemic symptoms like fever and malaise, for instance. Many have lesions that are localized to their genital and anal regions. Some have only a few lesions.

The discrepancy between what the medical literature describes and what front-line health workers are seeing adds to concerns that some people with monkeypox may not feel sufficiently ill to seek care or may not be recognized as having monkeypox if they do.

“That level of community spread is not being detected, and we cannot help people make good risk decisions, we cannot help people protect their loved ones and sex partners unless we know what’s going on,” said Joseph Osmundson, a molecular microbiologist at New York University. 

 Osmundson has prepared an online primer for men who have sex with men about the virus, with images of the anal and genital lesions caused by monkeypox and with information for people to provide clinicians to help them get a test. Community health groups are reporting that some people seeking tests have found that their clinicians are not willing to provide one, Osmundson said. 

“You may have to advocate for a monkeypox test as some providers are not aware of the situation,” the primer warns.

Currently if a medical worker suspects a patient has monkeypox, someone has to contact the state health department and send a swab from the patient to a facility in what’s called the Laboratory Response Network, which was set up to test for biological or chemical threats. These laboratories can determine if the sample is positive for an orthopoxvirus — the family to which monkeypox and smallpox belong. The combined orthopox testing capacity for this network is nearly 7,000 tests per week at 74 labs in 46 states, the CDC has said.

If the sample tests positive, the CDC conducts confirmatory testing. The CDC has said its two-step method has been sufficient thus far, and stressed that a positive orthopox test was being treated as a presumed monkeypox infection, activating all of the clinical and containment measures that a final diagnosis requires. That includes contact tracing, vaccination of high-risk contacts, and access to antiviral drugs for the patient, if warranted.

Ranu Dhillon, an instructor of global health at Harvard Medical School, said the testing system ought to be designed to normalize monkeypox testing, so that the net can be cast more broadly to find more cases. Dhillon, who works part of his time at a community hospital in Vallejo, Calif., said that as it stands now, he would need to clear the ordering of a test with the head of his hospital’s lab. 

“It would be a process, it would be a discussion,” he said. “I think the sooner we move to normalizing, the better to lower that professional stress or awkwardness of requesting a test for something that you’ve never seen [before]…. You have to be able to screen widely as we learn from Covid and have a lot of tests come back negative. That’s how you’re going to find the ones that are positive.”

Casting a wide net is critical because, though currently most cases are being detected in men who have sex with men, that’s unlikely to remain the pattern if monkeypox continues to spread. 

“Since the disease is unfamiliar to many, and quite variable in presentation, it is undoubtedly the case that there is undercounting, especially among the milder or atypical cases,” Paul Sax, an infectious diseases physician at Brigham and Women’s Hospital in Boston, told STAT in an email. “I’d also worry about a case being missed if it doesn’t fall into this currently high-risk group.”

Luciana Borio, a former director of medical and biodefense preparedness at the National Security Council, said the country should recall a lesson from the testing fiasco at the beginning of the Covid-19 pandemic and bring commercial diagnostic testing companies into the response. 

“We need to open up testing and bring testing to where it’s normally done. We learned that from Covid, right?” said Borio, who is a senior fellow for global health at the Council on Foreign relations. “It’s a lot more efficient.”

It will undoubtedly take time for companies to make and validate tests. But that work should be underway, she said.

“It has to start now — if it hasn’t already,” Borio said. “And it will take how long it takes. But we shouldn’t be debating whether it’s needed.” 

Create a display name to comment

This name will appear with your comment

There was an error saving your display name. Please check and try again.