Mankato - A City Fights Back!

This article is about the people of Mankato, Minnesota, a city of about 40,000 (not including the university, Mankato State) and their recent fight against an outbreak of a deadly bacterial disease among them. It is hoped that the information presented will help one to understand the nature of the disease encountered, to understand the extent of knowledge required to fight the disease, and to appreciate how well-organized efforts among the citizens of a community and state, can help us in times of crisis.

Most of us are unaware of the number of potentially harmful microorganisms to which we are constantly exposed. We take for granted that we either are somehow protected from, or can easily be cured of, diseases caused by bacteria or viruses. We think, "there may have been problems with this sort of thing years ago, but certainly not now." Then, with deadly consequences, an infectious disease can suddenly appear that reminds us of our vulnerability. At the same time, however, a crisis like this can bring out the best that is within us: it can make us acutely aware of the knowledge, skill, decisiveness, courage, resolve, and kindness of the people around us with whom we live and work; it can allow us to learn of the substantial professional assistance that can be mobilized from without and from within our community at almost a moment's notice, to help us. The people of the city of Mankato, and the State of Minnesota, having recently faced a serious threat to their well-being, learned these things - about one another - and about themselves.

The Crisis Begins

In late January of 1995, it became clear that a dangerous microorganism was threatening the city of Mankato. The bacterium Neisseria meningitidis was identified as the causative agent of meningitis cases that were appearing within the city - eight confirmed cases, one presumptive case to date - among people 18 years-old or younger, except for one 64 year-old person. Tragically, one young person, John Janavaras, succumbed to this organism.

[[ N. meningitidis is an organism that is relatively common within our environment, and can be a quiet inhabitant of our throat, never causing any problem. For as yet unknown reasons however, this bacterium can "rise up" and generate a deadly, swift-acting infection, which leads either to the disease called "meningitis" (an inflammation of the membrane which surrounds the brain, "meninges"), to "septicemia" (the organism enters the blood-stream), or to both. In either instance, the infection can incredibly quickly (within hours) overwhelm the body's defenses. This disease is primarily a disease of the young (for unknown reasons), and is particularly dangerous for the following reasons: many of the symptoms mimic those of other, common, less deadly, diseases - like the onset of the "flu" for example; and, the infection can spread so swiftly that there is not enough time to recognize what is happening until well-after the disease becomes established. It is only when someone becomes very seriously ill that medical personnel can become alerted. One issue is absolutely clear: this disease is nobody's "fault." There is no reasonable way to prepare for its occurence. ]]

Initial Identification of the Causative Agent

Local physicians, trained to recognize the symptoms of many possible diseases (meningitis among the possibles), had hospital laboratory personnel who were skilled in the identification and culture of disease-causing bacteria (pathogenic bacteria) examine blood, nasopharyngeal tissue secretions (swabs taken of tissue within the throat, and behind the soft palate - not on the tongue), and spinal fluid samples of the patient for the presence of bacteria. Bacteria were found; subsequently, the bacterial specimens were cultured (grown) under various conditions and pure cultures of the organism (isolate) were obtained. Through the use of specific biochemical tests (nutrient requirements, production of certain biochemical products) the causative agent was tentatively identified by the hospital as N. meningitidis.

[[ No organism of any kind should ever be present in spinal fluid or blood (always completely sterile) under normal conditions. Throat swabs were taken because it is known that a bacterial organism like N. meningitidis, or H. influenzae if present, will most likely be found on or near the tonsils, or behind the soft palate of the throat. N. meningitidis is the cause of approximately 27% of meningitis cases, while H. influenzae cases represent about 48% (usually restricted however, to the very young). There are, however, many other bacteria which can cause meningitis, e.g., S. pneumoniae, L. monocytogenes, M. tuberculosis, N. asteroides, S. aureus, S. epidermidis, Group B streptococci, and certain Gram-negative bacilli. And, viruses can also cause meningitis. Therefore, it is absolutely necessary first to determine if known bacterial agents are present, or if the disease instead is viral in origin. The treatment for these two possibilities would be very different and time is of the essence. If the infection is bacterial in origin, then antibiotic therapy is possible, but it is absolutely necessary to identify which bacterium is the causative organism in order to determine the best treatment (intensive therapy with the appropriate antibiotic or combination of antibiotics). ]]

Confirmation of the Identity of the Causative Agent

Immediately after the initial diagnosis and identification of the organism, the local and Minnesota State health departments, as well as local health clinics, were informed - medical personnel are trained to recognize when a particular infection may be a threat to the community, and there are established mechanisms which allow swift dissemination of information. Cultures of the isolated organism were sent to the State Health Department to allow this organization to bring its skills and substantial weaponry to bear to either confirm or refute the initial identification of the bacterial isolate. This investigational step is normal procedure when initial data suggest the presence of a particularly harmful organism, and allows objective confirmation or refutation of data (an important part of any scientific investigation). Subsequently, the State laboratories used serologic (specific antibody recognition) techniques and a technique called genetic finger-printing which confirmed the diagnosis and further identified the organism as a member of serotype Group C.

[[ One technique a pathology laboratory may use to identify an organism involves the ability of certain proteins, called antibodies (produced by the immune system), to react (to bind) specific molecular shapes. The use of antibody reactivity for identification is called serology. Antibodies have been prepared against a host of various infectious bacteria. Because of the ability of an antibody to very specifically react with certain molecules unique to a given organism, these antibodies can be used to identify an organism. If you stand and raise your arms above your head, you will "look" like an antibody. Your hands each represent a binding place - but your hands can bind only to one particular shape. If antibodies specific for a particular bacterial cell's outer-structures are added to a bacterial suspension on a microscope slide, the bacteria will "clump" together (agglutinate) if and only if the bacteria are the kind against which the antibodies were made. These antibodies are so specific that one can assign not only a general identity to the organism, but also an individual identity, e.g., a serotype. The genetic finger-printing technique utilizes the genetic make-up (DNA) of bacteria. As we know, the DNA of any organism is unique to that organism. And, while there may be similarities in DNA (sequence of the building-blocks) among organisms, there are also clear differences which have been identified. These differences are subsequently used to compare samples of DNA from among the various pure-organism cultures isolated from all patients, as well as to the DNA of known pathogenic organisms which cause a particular disease. Since different people may be infected with slightly different members (strains) of a given species of organism (in this instance N. meningitidis), but within any one individual there will usually be only one strain present, it becomes important to establish whether or not there is an outbreak of the same, different, or a previously unknown bacterial strain within a population. Therefore, one must carefully compare DNA samples prepared from many bacterial isolates to one another as well as to known DNA. Years of research have produced this information and methodology, which along with antibody recognition of substances on the surface of a cell, allows essentially unequivocal identification of potentially harmful organisms. ]]

Mankato Mobilizes

Once the diagnosis was confirmed, and as new cases appeared, Mankato began to organize to combat the threat. Health personnel know that transmission of this particular organism from one person to another depends, to a large extent, upon close and frequent contact among individuals. Therefore, children, faculty, staff, and administrative personnel in schools, as well as other people who work or live closely with one another in relatively "closed" surroundings, were known to be at more risk relative to others. There is only a minimal risk of acquiring this particular infection by simply visiting an area, for example. After more than one isolated case occurred however, health officials opted to perform general immunizations in order to be extra-cautious. Subsequently, health department officials, medical, city, and school personnel, and the community in general, rapidly arranged for a massive effort to disseminate factual information and to immunize the population of the city. A commercial pharmaceutical firm (Connaught Laboratories) was contacted which had many thousands of doses of N. meningitidis vaccine immediately available (information concerning who has vaccine is rapidly available through health-related networks pre-established for just such an emergency).

[[ Immunization is a process whereby a vaccine (usually made of killed specific organisms, or their products) is injected into a person. As a result of this injection, the body responds to the presence of this "foreign" material by generating cells and cell products which very precisely react with the injected material. This immune response literally increases the number of immune-system cells (called B and T cells) which react with the structures unique to the organism. These new cells populate the body's lymph nodes and spleen, and "remember" the structures. Subsequently, if a live organism bearing the same or very similar structures enters the body at some later time, a significantly greater number of these recognition-specific T and B cells are now available to respond against the invader and destroy it. More memory cells are produced as a result of this response, as well. ]]

Action is Taken

News releases were sent to Mankato (at least 12 separate ones ) from the State Health Department to be certain that everyone was informed of the situation. Local newspapers, radio, television, and city officials quickly organized to make periodic announcements to explain the necessity for becoming immunized, the location and schedule of immunization clinics and to whom to report. Local schools and a military facility rapidly organized to open their doors as temporary immunization clinics. The entire school system worked with the children and parents to try to calm their fears, to provide transfer of factual information, and to help explain to them what was happening. First, all school-aged children who were located at the site of the first reported case were immunized, the families of these children, then the faculty and staff, and then the families of the faculty and staff. Subsequently, all school-aged children were immunized, and later the general community, in order of risk. In essence, the entire community came together to solve this problem. For example, over 1,000 people per hour were immunized, for a total of approximately 30,000 people in just a few weeks! Over 3000 throat cultures were analyzed by the State Department of Health's laboratories! As one can imagine, to organize and perform successfully such an effort requires almost unprecedented cooperation among many hundreds of people. Volunteers were everywhere - from every walk of life - offering their time and/or particular skills to ensure that the effort succeeded. It was an amazing effort by Mankato and the state of Minnesota, and stands as an example to us all.

It is easy to forget that only about 50 years have passed since the first time in human history the antibiotic penicillin, became available. It is easy to forget that with only one or two exceptions, all of the vaccines now available were developed within the past 50 years, as well. We take for granted the routine of living, of being protected, either through immunization or the availability of all kinds of antibiotics, from harmful organisms which are always among us.

We take for granted the various organizations that have been established at every conceivable level within our nation, to learn about and develop methods to respond to any organism which threatens our health. We take for granted the breadth and depth of knowledge and skills of the persons within these organizations - those who perform research, who teach, who inform, who keep vigilance, who develop methodology, and who provide assistance, medical and otherwise, to address a threat to our health.

Mankato is quieter now, the long lines of people awaiting their turn for immunization are gone, and a sense of normalcy has returned. The situation will be monitored for awhile however, to be certain that all is well. Mankato is obviously a city filled with good people who reacted quickly, clearly and decisively to something which most of us are never required to face. We can learn from them, as they have learned from one another.

This article is dedicated to the memory of John Janavaras Age 14, who died on February 3, 1995, in Mankato, Minnesota.

Author, Jack Brown, Department of Microbiology, University of Kansas, Lawrence, KS, Copyright, 1995
I extend my sincere appreciation to the following people who so kindly gave their time and effort to allow this article to be written:
Stephen Collins of Web66 for the initial suggestion to write the article; Doug Johnson as my informational liason to the Mankato public school system; Yvonne Karsten for many helpful ideas and as the president of the community's WWW server site in Mankato; Shelly Schulz for city information and data sources; Buddy Ferguson as media coordinator of the Minnesota State Department of Health, and Kim Dayton (KU School of Law) for editing and content suggestions.