“And do you remember anything else that is probably unimportant?” said O’Mara.
Hewlitt took a deep breath and tried to ignore the sarcasm for Prilicla’s sake rather than the major’s, then said, “If we assume that physical contact is required for the creature to transfer to a new host, and it was continually interested in the possibility of making such a move, what about my interest in Leethveeschi and that doctor who drove into the ward in a pressurized tank? I am very sure that I wanted no physical contact with either of them, especially the charge nurse, so the curiosity could not have been mine. Does that mean the creature wastes its time on feelings that are impossible for it to fulfill, or is it capable of transferring itself to any living being regardless of species?”
O’Mara gave a short, irritated sigh. He said, “There was always the chance that you would add to the problem rather than help provide the solution. If you are right and our friend is not confined to transferring into warm-blooded oxygen-breathing hosts, that will seriously complicate our search.” He looked at the medics in turn. “Is such a radical, cross-species transfer possible?”
Diagnostician Conway was the first to speak. He said, “As close to impossible as makes no difference.
“Until Patient Hewlitt arrived among us,” said O’Mara with the sarcastic edge returning to his voice, “we thought it impossible for a microorganism that had evolved on one world to survive in a life-form from another.”
Conway did not take offense. He said, “That is why I said close to impossible, sir. However, there are major differences in the metabolism and life processes of a chlorine-breathing host, and the biochemical adaptation needed would be, again, close to impossible…”
“And who would want to live inside an Illensan anyway?” said Naydrad.
“As for more exotic life-forms like the TLTUs, SNLUs, or VTXMs,” he went on, ignoring the interruption and glancing toward Hewlitt to show that the explanation was for his benefit, “I would say with more confidence that they are completely unsuitable as hosts. The first breathes high-pressure, superheated steam in an environment which, in the old days, was used to sterilize infected surgical instruments. SNLUs are methane life-forms with a complex mineral and liquid crystalline structure which decomposes at temperatures in excess of eighteen degrees above absolute zero. As for the VTXMs, the Telfi are another hot life-form, not because of an elevated body temperature but because they need to absorb high levels of hard radiation to support their life processes.
“It follows that these three life-forms can be eliminated as potential hosts,” the diagnostician ended, “because a virus would be unable to survive in any of them.”
Before O’Mara could reply, Prilicla made an unsteady landing on top of an unoccupied piece of furniture. Its trembling was minor and of the kind, Hewlitt had discovered, indicating that it was nerving itself to the major effort of saying something disagreeable.
“It is possible that you are wrong, friend Conway,” it said. “And I, too, may be contributing to the problem rather than its solution because we cannot exclude the Telfi as possible hosts. Our virus was able to survive when its escape vehicle was in close proximity to the nuclear detonation that destroyed Lonvellin’s ship. The outer casing of the creature’s pod was partially melted and superficially damaged by flying wreckage, but it had also absorbed sufficient radiation for strong traces to be present after twenty-five years. At the time it took the young Hewlitt as a host, it had been occupying that pod and absorbing significantly higher, although diminishing, levels of radioactivity during the five years following the original contamination.”
“Oh,” said the diagnostician.
O’Mara actually smiled, although it was clear that his face muscles were unused to that form of exercise. He said, “Does anyone else want to make a fool of itself? Hewlitt, you are wanting to say something.”
For a moment Hewlitt wondered if the chief psychologist had an empathic faculty like Prilicla, then decided that it was probably the result of training, observation, and long experience. He shook his head and said, “It probably isn’t important.”
“If it isn’t,” said O’Mara, “I’ll be the first to let you know. Spit it out.”