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Scenarios
One of the lessons learned from bioterrorism exercises over the past two years is the value of identifying scenarios that raise questions about response procedures. The following scenarios are intended to illustrate the need for a formal mechanism for cooperation between states. The Mid-America Alliance seeks to effectively mitigate these types of situations through creation of protocols that have been pre-negotiated. It is assumed that none of these scenarios will warrant a declared state of emergency.
Scenario 1: Rubella Outbreak For a period of eight years between 1991 and March of 1999, the Douglas County Health Department had no confirmed cases of Rubella. Then, on April 1, 1999 a 29 year old Hispanic male residing in Omaha, NE went to a local Douglas county sexually transmitted disease clinic seeking treatment. His symptoms consisted of a rash, low grade fever, and lymphadenopathy and he tested positive for rubella. The patient stated that he worked at a meat-packing plant where seven additional cases were subsequently identified.
Rubella surveillance was subsequently enhanced throughout the county and the state, resulting in the identification of 100 confirmed cases between March 21st and July 31st. Of these 100 confirmed cases, 70 (70%) occurred among Hispanics born outside the United States with English as a second language, and 62 occurred either among workers in meat packing plants or residents of their households. For 15 individuals the exposure was unknown, however, these cases were closely tied to the Hispanic community where rubella was known to be circulating and the demographic characteristics of this group were statistically indistinguishable for the meat packing group. In addition, rubella also spread into the unvaccinated, US born, infant population. 17% (17) of the cases were associated with outbreaks in two child care centers geographically distant from the focus of the outbreak, with rubella cases identified in staff, enrolled children, and their parents. Thirteen Four cases occurred among pregnant women of which seven two were in their first trimester.
To put this situation in context, consider that in 1999 there were 267 cases of Rubella reported throughout all of the United States. Of these 267 cases, 100 (37%) were in Nebraska, and 87 (33%) were in Douglas County alone. Collectively, 267 cases are not enough to stress our nations’ resources, however, when 37% of the nation’s cases are concentrated in one state, the need for additional assistance becomes evident.
From 1969 to 1989, the number of reported cases of Rubella, annually, decreased 99.6% due to effective childhood vaccination programs. Unfortunately, two thirds of countries outside the U.S. do not vaccinate for Rubella (Consider that between January and June 1998, approximately 25,000 cases of Rubella were reported in Mexico). Not surprisingly, the meat-packing industry of Nebraska, where many Hispanic immigrants are employed, was struck the hardest by this Rubella outbreak. A significant need existed during the initial stages of the outbreak investigation for epidemiologists and nurses who spoke Spanish. The need for the ability to share epidemiologists and nurses with nearby states and counties was clearly evident.
Scenario 2: Pennsylvania Hepatitis A Outbreak During October and November of 2003, 610 people became infected with Hepatitis A and 3 others died. The source of the infections was traced to a restaurant in Monaca, Pennsylvania. The outbreak has been characterized as the largest in United States history. The cause of the hepatitis infections was subsequently narrowed down to shipments of green onions, received from Mexico, which were used in complimentary salsa offered to patrons.
The latent period of Hepatitis A contributes to the difficulty in identifying persons at risk. For this reason, approximately 9,000 persons who ate food at the restaurant in Monaca between October 3 and November 12 or had exposure to those who had eaten there were administered Immune Globulin injections. The green onions were likely contaminated with Hepatitis A Virus in the distribution system or during growing, harvest, packing, or cooling.
The outbreak was successfully controlled by the Pennsylvania Health Department and the CDC, however, it was apparent that had a major outbreak of another communicable disease occurred at the same time, the resources available would have been insufficient to effectively institute control procedures. The ability to draw on the resources of neighboring states would be essential in such situations.
Scenario 3: Anhydrous Ammonia Spill At 1:40 am, the morning of January 18, 2002 a Canadian Pacific Rail freight train derailed just West of Minot, North Dakota sending 31 of 112 cars off the tracks, completely rupturing 8 tankers, and releasing an estimated 300,000 pounds of anhydrous ammonia. Used as a farm fertilizer, anhydrous ammonia is a colorless liquid when stored below -33 C, but forms a gas at higher temperatures. Thus, much of the chemical vaporized, forming a toxic cloud that remained over the area. The clear, colorless gas can cause severe irritation of mucous membranes where moisture collects such as eyes, ears, nose, and throat.
In response, local emergency response officials sent more than a dozen firefighters and three fire-and-rescue vehicles to help rescue residents. In addition, eight bioenvironmental specialists helped officials track air quality until members of the mass-destruction civil support teams from the North Dakota National Guard and the Minnesota National Guard came to continue monitoring the air situation.
In the midst of the largest anhydrous ammonia spill in United States history, only one fatality resulted. In addition there were two critical injuries requiring intensive care, 13 non-critical hospitalizations, 320 individuals seeking immediate medical care, and over 800 individuals reporting symptoms temporally associated with anhydrous ammonia exposure. In many cases, door to door visits were performed to either evacuate individuals or assure their safety. The State Health Department had the need for a rapid evaluation of the people exposed to the gas. If more people had been available, as will be possible through the Mid America Alliance, the evaluation could have proceeded much faster.
Scenario 4: Viral syndrome outbreak at Utah Olympics (simulated) On February 16, 2002 a 35 year old Romanian man with a slight fever, respiratory symptoms, and cough reported to a medical tent at the Salt Lake City Olympics. Believing he had a cold, the man had waited to get treatment until he had become weak. It was also noted that the man had a prominent vesicular rash over the chest and back. In the meantime, the family had seen as much of Olympic village and participated in as many activities as they could during their brief one week stay in Salt Lake City.
Upon his arrival at the medical tent and unrevealed to the medical personnel, several members of the man’s family were also beginning to show skin lesions and low grade fever. Numerous tests were performed, including a scraping of the vesicles, after which the family was told to return for a follow-up visit. On February 18th, the family returned with two sisters, all displaying clear cases of chickenpox. The family was immediately quarantined.
Ten days later, people from all over the world, speaking countless different languages began appearing at the medical tent, all displaying the same symptoms as the Romanian man. All were given skin tests and quarantined. The Utah Olympic Committee began posting notices in every language warning of the symptoms and appropriate precautionary measures. Because of advanced planning, an excellent group of multilingual medical professionals had been identified to provide these services - a valuable resource that could become available to participating states that independently do not have the capability to provide these services.
Scenario 5: Laboratory Testing for West Nile Virus in Nebraska During the summer of 2003, Nebraska experienced one of the largest outbreaks of infectious diseases associated with significant mortality and morbidity in recent history. The event and the associated complications illustrate the importance of establishing supportive relationships between public health laboratories in the Mid West.
During the height of the epidemic, the Nebraska Public Health laboratory received 1000 specimens for processing in a single day whereas in the previous year, when cases of West Nile viral meningitis were appearing in states to the east of Nebraska, no more than 10 requests for testing were received in any week. However, the laboratory had not been idle as the impending epidemic had approached, but instead acquired an automated testing system that could handle up to 400 tests per day, a number thought more than adequate to meet expected demand. Not only was the testing process a challenge for the laboratory, but simply logging in the specimens into the electronic database required additional staff beyond that normally employed for up front processing. Therefore the laboratory personnel investigated whether surrounding states could help in the process and found that no single neighboring state could take the extra load, but that several labs were willing to pitch in and take a portion of the excess.
Unfortunately, two obstacles made the shared approach inefficient. First, while the NPHL could export and import standardized electronic laboratory messages, a common format had not been adopted in neighboring states and the hardware and software needed for the system was not in place. The CDC could accept standard lab messages into its system, but if the test was performed at the CDC, the data could not be transmitted back into the state Lab information system. The MAA, with its program for laboratory integration can effectively address a crisis such as this through efficient collaborative efforts and data exchange.
Scenario 6: Bordetella pertussis (Whooping Cough) Outbreak Pertussis (i.e. whooping cough) is a prolonged cough illness caused by the bacteria Bordetella pertussis. It is a highly contagious disease with up to 90% of susceptible contacts developing clinical disease following exposure to an index case. In the United States, 5000-7000 cases are reported each year. Major complications are most common among young children and include hypoxia, apnea, pneumonia, seizures, encephalopathy, and malnutrition.
Over a period of one month, a worker in an infant daycare center had an intermittent, nonproductive cough. During this period she continued to work at the daycare center and had close association with over 30 children attending the facility on a daily basis. The woman also had children of her own whose ages ranged from 2 years through grade and high school. Subsequently, a 2 year old male child that attended the daycare center became symptomatic. The child’s symptoms consisted of a low grade fever, and paroxysms that frequently ended with the expulsion of clear, tenacious mucus, also followed by vomiting. His mother took him to their private doctor who ordered the appropriate tests to rule-out an upper respiratory infection, including whooping cough. The laboratory tests came back positive and the local and state health departments were notified.
Whooping cough surveillance was greatly enhanced. The daycare workers children were tested and all were positive. The travel activity of the children ranged from attending their local high school basketball games during the holiday tournament, to traveling out state for a band competition. A contact investigation, conducted in several adjoining states, revealed over three hundred persons who were exposed to the children of the daycare worker. Subsequent testing revealed that 32 (approx 10%) of the exposed individuals tested positive. The contacts of these persons were then tested. Final results showed secondary and tertiary contacts that tested positive. In all, 43 cases were confirmed over a period of several weeks throughout three states. The epidemiology program of the MAA would allow for a more rapid analysis and mitigation of a diffuse outbreak such as this through a protocol of regional surveillance. Regional laboratory integration, also a central component of the MAA, would also aid through a rapid examination of potential infections.
Each of these challenges, standardized protocols, methods of data exchange, electronic connections, and operating procedures can be addressed using the approaches described in the Mid America Alliance project.
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