“Could mean a few things,” Kilburn said in his most soothing tone. “Antibiotics don’t work instantly. Most of them kill the bacterial cells when they’re dividing, which takes twenty-four to forty-eight hours minimum. Maybe the antibiotics simply have not had time to work yet. Or possibly, the bacteria growing in the sputum is not the cause. In other words, it might be a contaminant and the real source is a virus or fungus that can also cause this kind of pneumonia. Our …” He stopped himself.

“Or what?” Mallek asked, pulling at his oxygen mask.

“Or the bug in question—group-A streptococcus—is resistant to the antibiotics you’ve been treated with thus far.” Kilburn dismissed the idea with a wave of his hand. “But that’s only a theoretical risk, because the bacteria is known to be uniformly sensitive to both drugs.”

“So, what do we do?” Annie asked, rising from her chair.

Kilburn smiled and pointed at Tom’s chest. “We hit this infection hard. Very hard! I’m going to add a third antibiotic and antiviral medication, just to cover all bases. Meantime, you two hang in there. We’ll take it—”

He was interrupted by a knock. A tiny Asian woman in a lab coat reaching past her knees stood in the open doorway. “Sorry to interrupt, doctor,” she said in a Filipino accent. “I’m from the lab. The nurse told me to give you this.” She waved a single sheet of paper at him.

Kilburn walked over and took the page from her. “Thanks,” he said, closing the door behind her. Returning to the bedside, he glanced at the final culture and sensitivity report. He read the sensitivity report a second time to ensure he hadn’t misread it.

What the hell? he thought.

Despite his lack of expression, Annie picked up on his concern. “What is it?” she asked with a note of painful urgency. “Is it about Tom?”

“It’s the report on the bug in Tom’s sputum,” Kilburn said calmly.

“And?” she asked in a whisper.

He dropped his hand to his side. “I don’t know whether this is a lab mistake, but the group-A strep in the sample has not responded to the antibiotics as usual.”

“Oh my God!” Tears welled in Annie’s eyes and flooded over the rims. Her husband reached a shaky hand up to her face to wipe them away.

“Listen to me,” Kilburn said gently. He put his hand back on Mallek’s shoulder but stared into Annie’s eyes. “Our lab tests only a sampling of antibiotics. We have others to choose from. In a way, this could be good news for Tom. We might have found the reason that he hasn’t responded to standard antibiotics. Now we can bring out our biggest guns.”

Annie sniffed and nodded. The stream of tears slowed. The panic on both their faces subsided.