"I met with Dr. Ophelia again on Monday morning. The rain was over, and it was a fine spring day. We met by prearrangement at the hospital, and she introduced me at rounds to the other West Branch physicians. They gave me a very warm welcome. They were overworked and tired, and apparently under some pressure from the community. The point appeared to be that Ogemaw County is a summer-resort area, and a continuing epidemic could be bad for business. Also, I guess, a lot of the working population was laid up sick. We left the hospital, and I suggested to Dr. Ophelia that maybe I ought to have a look at the schools. There were two of them, and she took me around and I met the principals. One of the schools was the public school—a consolidated, all-grades school with an enrollment of around fifteen hundred. The other was a small Roman Catholic school. Both schools were within a block or two of the Houghton Avenue business district, and both were served by the same school buses. We then went on to Dr. Ophelia's office. It was almost ten o'clock and time for her to get back to the gamma-globulin program. The District sanitarian was waiting for us at the office. He's a very nice fellow named James Hasty. Mr. Hasty knows everybody in West Branch and almost everybody in Ogemaw County, and Dr. Ophelia had arranged for him to guide me around on my interviews and generally smooth my way.
"We took right off in my car. The family I wanted to call on first was a West Branch family I'll call Simpson. It was the largest family on the list, and it had the largest number of cases. I thought that might make for an instructive start. There were eight in the family—the parents, four boys (including twelve-year-old twins), and two girls. The children ranged in age from five to fifteen. Five of the children and Mrs. Simpson were sick. Only Mr. Simpson and one of the twins had escaped the epidemic. The Simpsons lived on the edge of town. Mrs. Simpson was in bed, too sick to see me, but Mr. Simpson happened to be at home. He and the five sick children told me what they could. There was municipal water in West Branch, but the Simpsons pumped their water from a private well. They bought milk from one or another of the Houghton Avenue stores, usually the A & P. They did their marketing at the same stores. They occasionally bought something at the West Branch Bakery, and they occasionally had a meal or a snack at one of the restaurants or one of the Dairy Queen drive-ins. There were two Dairy Queens in Ogemaw County—one in West Branch and one about twelve miles out of town on the Rose City road. None of the family had recently attended any large gathering at which food or drinks were served. Hepatitis was the only recent illness in the family. The children all were pupils at the public school. I took a sample of water for laboratory analysis, and then got down to the individual cases. What I wanted now were the onset dates of illness—when the first symptoms appeared. This was the essence of the interview. The onset date minus thirty days would give me the approximate date of exposure. We take thirty days as the average incubation period in infectious hepatitis. Mr. Simpson went upstairs and talked to his wife and came back With a calendar, and he and the children worked out the dates. The onset dates for the two girls were May 3 and May 4. The boys all three of them—took sick on May 5. Mrs. Simpson's first symptoms appeared four days later, on May 9. Well, that was a start. Those six dates made a kind of pattern. If the Simpsons were in any way typical, the epidemic had its beginning in early April
"They seemed to be entirely typical. Mr. Hasty and I made three more calls that day, and I interviewed four more patients One was a boy of eleven whose history almost exactly paralleled that of the three Simpson boys. His illness, like theirs, had begun on May 5. He, too, attended the public school. He occasionally had a meal with his parents at one or another of the Houghton Avenue restaurants, he sometimes had a snack at one of the Dairy Queens, and his parents traded at the A & P and most of the other food stores, including the West Branch Bakery. His history differed from that of the Simpsons in only one respect. The family water was municipal water. Two of the three other patients were a woman of thirty-nine and her eight-year-old daughter. She had become sick on May 11 and her daughter on May 10. The daughter attended the Catholic school. Their histories otherwise were substantially the same as the rest. The last patient I interviewed that afternoon was a man—a bachelor of thirty. He was a salesman. His illness had begun on May 13. That suggested that his exposure had occurred on April 13, but his records suggested an earlier date. They showed that he had been out of town between April 11 and April 13, and from April 15 to April 20. April 14, the one day in that period when he had been in West Branch, was a Sunday, and he had spent it at home. His general history, with one exception, was much like that of the others. It included municipal water, the A & P and other markets, the restaurants, and the two Dairy Queens. The exception was the West Branch Bakery. He said he never set foot in the bakery. He and the owner had quarreled. I thought about that on the way back to the office. I had practically decided that water and milk could be eliminated as likely vehicles of infection here. And now I thought maybe we could drop the bakery, too. I mentioned this to Mr. Hasty. He agreed about water and milk. The community was about equally divided between municipal water and private wells, and all the milk came from sources outside the county. But about the bakery-the fact that the salesman never traded there didn't really mean very much. The bakery was more than just a store. It also supplied bread and pastries to most of the markets in town, and to all of the restaurants.
"I talked to Atlanta that night. I didn't have much to report, but they had some news for me. They were sending me some help. He was a fellow EIS officer named James M. Gardner. Gardner was between assignments. He had just finished an assignment at the Michigan State Public Health Department, down in Lansing, and he wasn't due to report for his next assignment—in California—until the following Monday, so they had asked him to spend the interval up here with me. He arrived on Tuesday morning. I hadn't asked for help, but I was glad enough to have it. I got gladder as the week went on. Eight more cases were reported on Tuesday, four more came in on Wednesday, and on Thursday (here were six. That brought the total number of cases in West Branch and the rest of Ogemaw County up to fifty-seven. It would have taken me two weeks to see that many people, but with Gardner to help it only took three days. By Thursday night, we had seen and interviewed all the West Branch cases and most of those in the outlying county. The results were all we had hoped for. They were even more than that. We got a good epidemic curve. It was virtually the same as our final curve. It showed that the epidemic began with a single case on April 28, built to a peak of thirteen cases on May 12, and then dropped to a final case on May 20. All but five of the cases had had their onset between May and May 14. This clustering was very instructive. It indicated the time of exposure—around the middle of the first half of April. It established what we had only assumed before—that all of the cases were infected by the same source. They were too close together to be related in any other way. And it told us that the epidemic was either ending or already over. But that wasn't all, Those were merely the formal results. We learned some even more interesting things in our travels around the county. One of these was that the epidemic might be wider in scope than any of us had supposed. Several people we talked to had friends or relatives living elsewhere who had been in West Branch recently and who now were sick with hepatitis. Or so they said. We also heard and confirmed that there had been some hepatitis in the community about a month before the epidemic began. There were two cases in particular. One was a girl who worked at the Rose City Dairy Queen. She left work sick on April 4. The other was a man I'll call John Rush. Rush was a baker at the West Branch Bakery, and he took sick on April 6.
"We sat down with Dr. Ophelia on Thursday night and had a conference. The question was what to do next. There was an embarrassment of promising possibilities. Talk to Rush? Talk to the girl? Look into those outside cases? And we still had a few more county cases to see. We decided to let the county cases wait. They couldn't tell us much that we didn't already know. Rush and the girl were a different matter. They were very interesting news.
Either one of them could be the index case—the source case of the epidemic. They both were sick at the right time, and they both had jobs that had to do with food. The girl's job was especially provocative. She made us think of a recent classic case—an epidemic in Morris County, New Jersey, in 1965 that was traced to contaminated strawberry sauce in an ice-cream drive-in. But, of course, that wasn't enough. Our histories showed that everybody seemed to patronize the Dairy Queens, but they also showed that everybody seemed to patronize the bakery, too. We needed something stronger than suspicion. We needed something that would narrow the field a bit. That brought us around to the outside cases. A visitor to West Branch would probably have fewer contacts than a resident. There was one presumably outside case within reasonable reach. She was a schoolteacher I'll call Miss Brown, and she lived in the village of Au Gres, on Saginaw Bay, about thirty miles southeast of West Branch. We decided she was worth an immediate visit. Our information was that she had been in West branch recently. It could be very helpful to find out when and where.
"The three of us drove down to Au Gres the next morning. That was Friday, May 24. Dr. Ophelia was able to come along because the gamma-globulin program was just about over. She was determined to be in on Miss Brown. She had the same feeling that Gardner and I had that this could give us a lead. You may wonder why we didn't just pick up the telephone and give Miss Brown a call. The reason is this. The epidemiological experience has been that telephone interviews are seldom satisfactory. A telephone conversation is too abrupt, too remote. People make more of an effort when they're talking face-to-face. So we paid Miss Brown a visit. She was sick, but not too sick to see us. There was no doubt about its being hepatitis. She was still icteric—still jaundiced. Dr. Ophelia handled the introductions. Her presence was invaluable. She helped Miss Brown to relax and think back and remember. Miss Brown's memory was excellent. As a matter of fact, it was exhilarating. The chronology of her illness placed her squarely in the epidemic. Her onset date was May 5. It was true that she had been in West Branch recently. She had stopped there twice in the past three months—on March 20 and again on April 5. But only very briefly. On the first occasion she had a cup of coffee in one of the restaurants. That was all—just a cup of coffee. She was sure of the date because her mother had died the day before and she was on her way across the state to Petoskey for the funeral. Fetoskey was her home town. She drove back to Au Gres on March 23, but this time she didn't stop at West Branch. She was also sure about her second West Branch visit. April 5 was a Friday and the beginning of spring vacation, and she was driving to Petoskey again to spend the holiday with her father. It was late afternoon, and she was hungry. She stopped in West Branch and went into the bakery there and got something to eat on the way. She bought some pastry—a piece of coffee cake and three cupcakes with yellow Easter-bunny icing. That definitely was on her way to Petoskey. It couldn't have been on her return. She returned on April 14, and April 14 was a Sunday—Easter Sunday. We thanked Miss Brown and marched out to the car and headed back to West Branch. We sang all the way."
Miss Brown's emphatic testimony marked the end of the floundering phase of the West Branch study. It also marked the end of Dr. Gardner's participation in the investigation. He left on Saturday for his new assignment in California. Dr. Schoenbaum was alone again, but again for only a day. He spent that day on a final round of interviews. Four more cases had been reported since Thursday That brought the epidemic total up to sixty-one. By Sunday night, however, he had histories on them all. His new reinforcement arrived on Monday. He was an EIS officer on loan from the Shelby County Public Health Department, in Memphis, named E. Eugene Page, Jr. Dr. Schoenbaum and Dr. Page spent Monday afternoon and evening at the Tri-Terrace Motel reviewing the collected case histories. They spent Monday night at the West Branch Bakery.
"We got there around midnight," Dr. Schoenbaum says. "That was when their baking day began. They baked six nights a week—Sunday through Friday. I had already talked to the owner and made the necessary arrangements, and he was there to meet us and show us around. I had explained the nature of hepatitis and told him what we knew about the epidemic. I told him that it unquestionably stemmed from a common source, and that we had some evidence that the source might be his baked goods. One of his people, as he knew, had been sick with hepatitis back in April, and he could be what we called the source case. Our evidence wasn't proof, but it was enough to require an investigation of the bakery. We wanted to see how the baking was done. We wanted to see if bakery goods could be a source of infection. The owner was extremely cooperative. He could very easily have been hostile and difficult. In return, I assured him that we wouldn't publicize our visit. We would keep it a secret until the end of the investigation. There was no chance that anybody would see us arrive. West Branch is asleep by midnight.
"He let us in the back door. The back room was the baking room. There were two bakers—the head baker and Rush. The owner was also a baker by trade, but he didn't do much baking anymore. Only when they were shorthanded. He worked days in the shop up front, and after introducing us, he left and went home. Page and I stood around and watched the bakers work. They were mixing dough. There was a bread dough and a pastry dough. They mixed them separately, but they mixed them both by hand. They did everything by hand—mixing, kneading, shaping. Even when they used a mechanical mixer, they scooped the dough out by hand. Rush was older than the head baker, and he was nice and friendly, but he didn't look very bright. But he seemed to know his job. We watched them, and it was interesting for a while, and then it began to get boring. It also began to seem like a waste of time. Rush and the bakery was our one big hope. The Dairy Queen girl had just about dropped out of sight. The case histories made her very unlikely. When we checked them over carefully, it turned out that her Dairy Queen wasn't as popular as we had thought. It was the other Dairy Queen that most of the people went to. She might have been the source of a case or two, but she couldn't be the epidemic index case. That was Rush. Or so we thought until we watched the baking. He had every opportunity to contaminate the dough, but the dough was only the beginning. It then went into the oven and baked for half an hour or more at a temperature of at least three hundred and fifty degrees. Thirty minutes at anything much over a hundred and thirty degrees will kill the virus of infectious hepatitis.
"But we stayed and watched. They made some doughnuts— fried cakes, they called them—and cooked them in boiling oil. Our hopes got dimmer and dimmer. They offered us some of the fried cakes, and Page ate a couple. I declined. I don't know why exactly. There wasn't any risk. Rush was fully recovered, and the head baker had never even been sick. I said I wasn't hungry. I really wasn't—I couldn't have eaten anything anywhere just then. The time dragged on. Around three-thirty, they finished baking and emptied the ovens and stacked the bread and rolls for sale in the shop up front or for delivery to the store and restaurant customers. The next step was icing and glazing the pastry. Some of the frostings were already cooked and ready to use, and some they made without cooking. They started in by glazing the fried cakes The glaze was in a five-inch pan about five feet long. What they did was take a double handful of cakes and dip them in the glaze and turn them over and around and then lift them out and line them up on a rack. That was glazing. That was the entire process But it was a revelation to us. Page and I were wide awake in a minute. The process was much the same with the other kinds of pastry. I remember at one point Rush was up to his elbows in glaze. He piled a load of fried cakes on the rack, and then turned and walked across to another counter and started icing cupcakes. He didn't bother with a pastry tube. He used his hands—the same bare hands he had used on the fried cakes. He scooped up a handful of icing and squeezed it out through his fingers. He was an expert. He did a beautiful job. It was horrifying. Page and I could hardly keep from shouting. They called the West Branch Bakery a home bakery. What they should have called it was a hand bakery.
"Rush was almost certainly the index case
. We watched and asked questions, and by five o'clock, when we finally called it a night, we had everything we needed but proof. Rush had had every opportunity to contaminate the pastry, and also had had the capacity. His understanding of hygiene was very primitive. Baking was the only protective process. Anything that was contaminated after that would stay contaminated forever. Watching Rush work, we began to wonder when the contamination might have occurred. Did it happen on a succession of nights? Or on a single night? We found that a single contamination could even account for people being exposed over a period of several days. The head baker told us that unused glazes and icings were carried over from one night to the next. He said they often used leftover glaze to start a new batch. We also learned that the bakery regularly sold day- old pastry as well as day-old bread. And not only that. Unsold pastry was often frozen and sold a few days later. The hepatitis virus can be killed by freezing, but not that kind of freezing. A few days isn't long enough. It takes a year or more. All of those points were persuasive. We began to incline toward the idea that the contaminated pastry was contaminated in the course of a single night. It actually seemed more probable than a series of accidents-even for a man like Rush. The night that seemed most probable was the early morning of Friday, April 5. It was supported by the clustering of onset dates, and by Rush's own experience. April 6 was the day he consulted a doctor—the apparent date of onset. Hut he had obviously been infectious at work that Thursday night and Friday morning.
The Medical Detectives Volume I Page 25