A local infectious disease expert has just phoned you for advice on two disturbing cases that have recently appeared in her hospital. The first is a 60-year-old man who was weak from several days of vomiting and diarrhea. Despite the administration of IV fluids, the man continued to get worse. He became confused and then started experiencing paralysis in his arms and legs. Doctors could not find a cause and none of the conventional treatments for sudden paralysis seemed to be helping. The second patient is a 75-year-old man who was brought in with a high fever, shaking uncontrollably. He, too, developed paralysis over the next few days. Their symptoms are consistent with some type of encephalitis, but the doctor is unable to find a cause.p>

Day one: afternoon

The infectious diseases doctor called back while you were on your lunch break. Two more cases have come to her hospital resembling the first two. An 80-year-old man admitted for a heart attack had a high fever and had now developed paralysis. And 87-year-old woman brought in with severe, flu-like symptoms had quickly progressed to the same weakness. Doctors from other area hospitals have also called with five more similar cases. You have received blood, urine and CSF samples from one of the case patients. Additionally, this patient’s stool has been cultured and the plate has been sent over for you.

Day two: morning

Four more cases have been reported, all at the same three hospitals as the previous cases. An assistant has been out to one hospital visiting patients and was fortunate enough to be in the emergency room when the latest case was brought in. A 57-year-old man was suffering from high fever and hallucinations and was fighting attendants hard enough to need to be restrained. Your assistant noted that all of the patients were older adults, mostly male. None of them showed any outward signs of other illnesses or appeared to have been sick for long before hospital admission. In fact, he noticed that most of the patients were well tanned and appeared to have spent the days before their admission outdoors.

Day two: afternoon

Three more cases have been reported and investigators have been dispatched to the patients’ homes to look for clues as to what may be causing this outbreak. In the process of assigning investigators to the various homes, it was noted that all of the patients live within the same neighborhood. Attached is a map of the area and a sample of the reports filed. The homes investigated were as follows: private, single family residences on 97th street at 94th Street Junction Blvd., Elmhurst Ave. at 94th Street Junction Blvd., 98th Street, 99th Street and 100th Street and 3 separate units in the same apartment building on 96th street near 34th Ave., four apartments in separate buildings on 103rd street between Northern Blvd. and 37th Ave., an apartment on Benharn Street, an apartment at Roosevelt Ave. and 97th street and two neighbors in an apartment building at 105th street and Northern Blvd.
An outbreak of an unexplained rash has been reported among children at day camps in and around the same neighborhood as the homes of many of the encephalitis patients. Children who appear healthy in the morning complain of itchiness and discomfort by mid-day. By the time the children are sent home, they often have headaches and low-grade fevers. The rash generally clears within a week and the children are back at camp. It is unclear if this bears any relation to the adult outbreak, although it has been noted that no other unusual illness has been seen among young adults and children.

Day three: morning

Two more cases have been reported by a hospital in an adjacent neighborhood. These patients matched the case histories of the previous patients in both age and symptoms. Both were reported to have been healthy in the days prior to hospital admission. Two of the patients reported on day one have died.
At a citywide infectious diseases meeting this morning, an official from the city zoo noted that she had recently seen a number of exotic birds dying of unknown causes. The animals all seemed to become disoriented and lost motor control prior to death or euthanization. Although the hospitals exotic birds were being swept with this epidemic, the farm birds kept in the Children’s Zoo remained healthy. Autopsy samples of two flamingos and a crane had been sent to the National Veterinary Services Laboratory and a researcher there had called this morning to report that a flavivirus was isolated from all three animals.
Cases are starting to appear in areas immediately adjacent to the initial outbreak region. Patients are overwhelmingly middle-aged to older adults who, prior to their illness, were considered to be relatively healthy and active.