2:00 AM, a university hospital ED. Marcus, 34, presents with fever and myalgias that began hours ago, six days after returning from a humanitarian mission in central Africa.
Ebola is undetectable by PCR for up to three days after symptom onset. Marcus has been symptomatic for hours. The specimen ships frozen as a Category A substance; the team is flying blind for days, and has no way to rule out a bacterial process that might need aggressive treatment of its own.
Now run it again with Q-SENS. At 2:15 AM, while triage is still underway, a fingerstick drop goes onto the cartridge. The first readout returns in ten minutes, and crucially, it includes procalcitonin, the body's most reliable early signal of bacterial infection.
The PCT at 2:15 delivers the first decision: this is not bacterial sepsis. PCT stays flat across all four readings while the pro-inflammatory cytokines accelerate. That combination is a signature.
By 8:15 AM, four serial readings have painted an unmistakable picture. The PCR confirmation arrives two days later. It is positive, but the hospital's response had already been running for eighteen hours.
| Time | {MARKER_COLS.map((m) =>{m} | )}
|---|---|
| {r[0]} | {r.slice(1, 7).map((n, j) =>
A rising cytokine trajectory paired with a flat PCT, read serially over six hours, says two things at once: how fast the fire is spreading, and that antibiotics alone won't put it out.
Maya is 23, finishing grad school and managing Crohn's. The frustrating part isn't the disease, it's the waiting. Every medication change is a stone dropped into a well, listening for a splash that might come in six weeks, or eight, or not at all.
Q-SENS measures her five-cytokine panel from a fingerstick every Monday morning, before her first class. It takes less time than her coffee. Six stable weeks become her personal baseline, not a population average. Hers.
Four weeks into a switch from adalimumab to ustekinumab, her symptoms haven't changed. But the read tells a different story: TNF-α is trending down, IL-10 is quietly climbing. Her gastroenterologist calls it before either expected to, this one's working. They don't wait three months to find out.
Weeks later, during thesis deadlines and a respiratory infection, her IL-6 spikes on a Tuesday. Not a full flare cascade, yet. They adjust her dosing interval. By the following Monday, the number is coming back down. The flare that was building doesn't fully arrive.
She went from reacting to anticipating. From waiting six weeks for a maybe, to knowing in three.