The cruise had been a gift from Ed and Nadine Worth’s four children in celebration of their 30th wedding anniversary. The weather had been perfect, the seas calm, and the couple of cannot remember ever having so much fun. The fun however stopped on the third day after an outing in Mexico, as the couple began to suffer from seasickness. After visiting the clinic, the doctor on duty, Mary Tamworth, MD, prescribed meclizine for the nausea and suggested a few hours nap would make all the difference. Both Ed and his wife were from a generation where being sick from time to time was expected and the couple certainly had not wanted to trouble the doctor with what they also assumed to be seasickness. One method of fighting seasickness that is both easy and often effective, is eating ginger, in this case Ed and Nadine snacked on ginger cookies while waiting for the nausea and rolling in their stomachs to subside.
That afternoon the one of the ships doctors, Cheryl James, MD, saw four more couples that were complaining of nausea, stomach cramps, and headache. They were also prescribed medication for seasickness and told to rest. In all, the main clinic on the ship saw a total of 46 guests for seasickness that afternoon. This was generally not surprising during rough weather, however the seas had been remarkably calm all week. This was pointed out by one of the nurses, and answered with a shrug from the ships head nurse, and no more thought was given.
The head physician, Mary Tamworth, MD, was having lunch with the ships health and safety director, an epidemiologist by the name of Stan Grenier. Not unusual, as Dr. Grenier enjoyed spending time with his staff and liked to get a feel for how things were going while at sea. He knew full well that in the event of a serious emergency, medical help may be hours or even days away. Dr. Grenier casually mentioned how smooth the cruise seem to be going, which was in large part due to the perfect weather and calm ocean. Dr. Tamworth smiled and replied that regardless of the weather and the sea, people were still getting seasick. In her clinic just yesterday they had seen over a dozen people and treated them for seasickness. On a ship of nearly 5500 passengers and crew, a dozen people being seasick was nothing for concern. That was about to change.
Dr. Tamworth had been about to order dessert when her pager went off. The staff at the clinic was in chaos. Over 100 people were now sitting in the treatment center and waiting room complaining of seasickness. Most alarming to her was that nearly a dozen of the people with seasickness were crewmembers; some had been on the ship as long as she had. The weather had been significantly rougher on other cruises without crewmembers needing treatment. Both Dr. Tamworth and Dr. Grenier immediately left for the clinic.
The number of sick passengers and crew had now grown to well over 150, and both sides of the companionway had been lined with folding chairs in a makeshift triage center. All the nurses and physicians, both on and off duty, had been called in to deal with the calamity. Ed and Nadine occupied two of the chairs, and Nadine was now visibly quite ill. She had her head on Ed’s lap and he was stroking her hair. Dr. Tamworth remembered the couple and immediately knelt beside them. She asked about their symptoms. Had the medication helped at all? It had not. Ed said that not only did they feel nauseous with stomach cramps, but also now they couldn’t keep any food down, not even the ginger cookies. Nadine had had extreme diarrhea and was now looking weak and pale. Dr. Tamworth got a stethoscope and cuff, and after taking Nadine’s blood pressure, turned to Dr. Grenier with a horrified look and simply said “this is not seasickness.” Nadine’s blood pressure was 90/40. Was she taking any medication for blood pressure? Ed replied “no.”
Dr. Grenier knew that some unknown agent was making people extremely and violently ill on the ship, and it was his job to discover what it was. After obtaining a list of the most prevalent symptoms from the nurses and physicians, Dr. Grenier had a starting point. The first symptoms had been headache, nausea, stomach pain, and dizziness. This had begun yesterday at approximately 9 PM. Since that time, nearly 200 persons had reported to the clinic complaining of the same symptoms. The first persons to be seen for seasickness were Ed and Nadine, and Dr. Grenier immediately went to speak with them. Nadine was in terrible shape, she was pale, cool to the touch, her eyes were closed and she moaned softly. Ed didn’t look much better, yet he tried desperately to comfort his wife. Dr. Grenier noticed tremors in Nadine’s arm, and asked if she had a medical condition that would complicate her treatment.
Ed explained that his wife had always been in near-perfect health, aside from four pregnancies. He too had noticed the trembling but assumed it was because of the nausea. Dr. Grenier recognized the ataxia as not being a usual symptom of seasickness, and grabbing a pad of paper from his pocket and a pen asked a series of questions. Head either of the couple experienced any changes in breathing? Yes, Ed responded both had developed a slight cough and sometimes the breath was hard to get. Taking Nadine’s pulse, Dr. Grenier found her heart rate was 140. Embarrassingly, and almost as a second thought, Ed commented that his wife had wet her bed last night. Nadine gave him a stern look but at this point she was beyond caring about the embarrassment.
Where there any other symptoms, anything strange? Ed reported that even with his glasses, things seemed blurry and he had difficult time seeing shapes at a distance. He went up on deck but the sun hurt his eyes. It felt better if he kept them closed.
Dr. Grenier stood up in the hallway and shouted for everyone to please be quiet for a moment. Then he asked a series of questions that would help him diagnose this mystery illness. He asked for a show of hands from all the patients who had experienced nausea, vomiting, diarrhea, heart palpitations, dizziness, shaking or tremors, and blurry vision. Every patient’s hand went up. He looked around and saw that nearly everyone had sweat stains on their clothing, despite the ship wide temperature of about 71°. Dr. Grenier’s next series of questions would help him pinpoint the cause. Dr. Grenier had stopped at the main dining hall last night for a cup of coffee. He had eaten a sandwich in his room while reviewing safety reports. He recognized several crew members were also there.
How many had eaten in the main dining hall last night? Every hand went up. How many had eaten the chicken? Not quite half. That ruled out campylobacter. How many had the beef? A little more than half. Dr. Grenier thought for a moment. Listeria, Salmonella, or even E coli were possibilities. If it was Listeria, that could explain almost all of the symptoms and could be from the chicken or the beef. The symptoms fit. Ed spoke up at this point saying that he had had the chicken, however his wife had neither chicken or beef. She was a vegetarian. So much for that idea.
Dr. Grenier thought for a second. How many had eaten at the salad bar? Again, all hands went up. Dr. Grenier and Dr. Tamworth ran to the main dining hall kitchen and prep room. They needed to locate what was making the passengers and crew so ill. The main dining hall had always prided itself on the use of fresh produce rather than canned or frozen. However, in the winter it was often difficult to acquire fresh produce. The ship would often take on stores during its various stops, and the last stop had been in Progreso on the Yucatán. Dr. Grenier told Dr. Tamworth to look for any vegetable box or package that was written in Spanish. Dr. Tamworth saw a stack of boxes in the walk-in cooler. Among them, 4 crates marked “Ejotes.” Green beans. Indications pointed to the green beans having been treated with a pesticide of some form and not adequately cleaned before serving.
Dr. Grenier had the final piece of the puzzle. He advised the staff to quickly take blood pressures from all the patients and those who had low BP were to be started on anti-arrhythmic agents and atropine. These same patients should also be administered O2 at 100%. The rapid heartbeat, low blood pressure, blurred vision, ataxia, and the diaphoresis all pointed to organophosphate poisoning.