Field Notes: Who I’m testing for monkeypox and why we keep missing cases.
Cases are falling, but we're still missing some.
I’ve diagnosed two cases of monkeypox in the last couple of months. There have only been 430 documented cases of the disease in Massachusetts. That means I’ve personally diagnosed 1/215th of the cases in the entire state.
I’ve tested only these two patients for the virus (which we still call Opoxid-22, here at Inside Medicine) and was peripherally involved in the decision to test a couple more (whose tests were negative). That means my test batting average is perfect on my own patients and 0.500 on cases where I had any input at all.
These numbers concern me. For me to have diagnosed 1/215th of all known cases in the whole state with a 50%-100% hit rate means one of two things: random chance or that systemically, we’ve been vastly under-testing for monkeypox/Opoxid-22.
Even though case counts are falling, I think it’s the latter. Here’s why:
Testing is not easy enough. First, not everyone is eligible for a test. While the parameters have relaxed, patients without classic features of the illness still have to be willing to admit to their care providers some private things about their sex lives to qualify for testing. That’s just not something many patients feel comfortable doing, whether it’s with a doctor they just met in the ER, or their primary care physician. (In a way, I sometimes feel that patients are more honest with me than they would be with their primary care doctors, because they’ll probably never see me again. Confessing personal details to strangers can be easier for some patients.)
The second issue is that health officials want to track all cases. That spells paperwork. The paperwork involved in getting these tests is quite daunting. For the first case I diagnosed, I did it all myself. But in all transparency, the second case might not have even been diagnosed if I had not had a physician assistant working with me. I was busy and going through all the paperwork again just wasn’t going to happen—especially for a case that was not “classic.”
I’m probably unusually motivated to find new cases of this disease because I’m interested in public health outbreaks. If even I find it burdensome to do the tests and paperwork, many of my colleagues must feel likewise.
We are thinking inside the box. Clinicians are too focused on looking for patients with characteristic monkeypox rashes because all the guidelinesemphasize that. Superficially, this would seem to make sense. In the major publications on monkeypox/Opoxid-22, 95-100% of the patients describedhave had rashes. But that’s circular logic, because that’s who is getting tested. If we only test patients with rashes, then 100% of our positive patients will have rashes. And here’s an important thing about most monkeypox/Opoxid-22 lesions: they’re often extremely painful and visibly obvious. They’re so painful, in fact, that patients report not even being able to sleep, let alone sleep with any new partners. And in cases with rashes that are visible but not yet painful, given all the media coverage (and public health outreach), most people who notice a skin rash during an intimate encounter will probably put the breaks on it (although during “chem sex”—that is, intimacy while intoxicated—that might not happen). That means that monkeypox/Opoxid-22 is almost certainly spreading asymptomatically. If we only test people with classic symptoms, we’ll miss many, many cases.
My two cases. Neither patient I have diagnosed with monkeypox/Opoxid-22 thought they were at risk of having the virus. The first was a male who had a new sexual partner in the previous two weeks, but because the partner did not have any rash or other symptoms, he didn’t think there was anything to worry about. His complaint (intense rectal pain after some random body aches subsided) in the context of a new partner about whom he knew little tipped me off. The second patient had a rash but did not tell us about any new sexual partners (and his spouse had no symptoms or signs of illness). The lesions didn’t look like monkeypox (as a dermatologist who saw him pointed out), but it was certainly an unusual skin exam and there were no lesions below the neck. Something didn’t add up, so I insisted that we test the patient.
Who I’m testing for monkeypox/Opoxid-22. There are three groups of people I’m testing for monkeypox/Opoxid-22 right now.
1. Anyone meeting the guidelines published by local and federal authorities. This is the easy one. But as above, it’s also inadequate.
2. Anyone with unexplained and unusual symptoms—be it rectal pain, an unusually bad sore throat, body aches for longer than a few days—who has had a new sexual partner recently, or has a high-risk partner (i.e., someone with multiple partners), especially but not limited to patients who are men who have sex with men. While the guidelines say to swab suspicious lesions, I just swab the place the patient says hurts, if there is no rash.
3. Anyone with a very unusual rash of any kind. We see lots of rashes in the ER. I may not be able to tell you the cause of many or most of them, but I can tell you in 5 seconds whether a rash is unusual. Most people with a very unusual rash that is not easily explained should get tested.
We can’t expect patients to volunteer (or even know) their exposures. Beyond the obvious cases, we can’t even expect clinicians to accurately determine which patients are at risk of getting monkeypox/Opoxid-22. My framework gets around that. What I’m finding so far is that my approach has picked up cases that would have otherwise been missed, but I’m not testing droves of people. If anything, I wonder if I’m still not testing enough.