Table of Contents

Chapter One - Why Should You Read This Book?

Chapter Two - Anthrax Basics

Chapter Three - Anthrax Medical

Chapter Four - Anthrax Detection

Chapter Five - Anthrax Prevention/Decontamination

Chapter Six - A Perspective On Health Risks

Chapter Seven - Psychological Considerations

Chapter Eight - Summary

References/Additional Sources of Anthrax Information

Sample Chapter

CHAPTER FOUR

Anthrax Detection

Recent pictures of workers in white suits and respirators have piqued the public's curiosity. While there are some methods for detecting anthrax, vaccinations of livestock have been so successful in preventing the disease that little research has been performed in this area. Hopefully, recent events are already causing a surge of research in new anthrax detection methods. Here are the some of the current procedures that are used to determine if anthrax is present in the environment and the host organism, respectively.

Detection in the Environment

Currently there are no widely accepted ways of measuring anthrax spores in the open environment. Traditional sampling devices for measuring air quality do not normally focus on capturing microbes. However, air sampling devices that use pumps and adsorbent material to capture airborne particles can be used to capture anthrax spores if the concentration of airborne spores is high in the sampling area. Identification of the spores can then be accomplished using traditional laboratory methods.

To measure if anthrax spores are present in buildings or other more contained structures, wipe samples are collected from any potentially exposed surfaces. Over the last several weeks, extensive wipe sampling has been conducted in any building/structure (post offices, federal buildings, homes, and bodies of potentially exposed employees) where anthrax exposure may have occurred. Likely candidates for wipe sampling include the ventilation system, walls, floors and any objects that are believed to have contained anthrax. Wipe sampling procedures vary somewhat, but here are the procedures being used to sample buildings in Washington, D.C.

A piece of sterilized gauze is soaked in water (this water-soaked gauze becomes the wipe sample). The wipe sample is then rubbed on a potentially anthrax-contaminated surface. After contacting the potentially contaminated surface, the wipe sample is quickly placed in a sterilized metal tube. The metal tube is placed in a plastic bag and the plastic bag is dipped in bleach to sterilize the bag. The bag containing the metal tube is placed in a second plastic bag. Both bags are sealed to ensure that no other sources can contaminate the sample. The samples are then transported in coolers that are also sealed. Each sample has a unique number and label that is recorded in multiple places to ensure the sample can be tracked from the sampling site to the laboratory. This allows the very specific determination of where the anthrax spores were detected.

After an office space or building has been sampled, any potential bacteria are cultured for identification. The oldest and most accurate way of culturing bacteria is to touch the wipe sample to agar or other laboratory nutrients that promote growth of the bacteria. This process of seeding the bacteria and waiting until a sufficient colony is produced for identification is time consuming, usually taking several days. To rapidly produce and test a large number of samples, a single sample can be diluted into many less concentrated samples so multiple cultures are available for identification and testing. Immunoassay test kits can also be used as a rough, field administrated test, but the results are not always accurate. An extremely rough field test is to put a sample of any white powder that has been found in water. If it completely dissolves in a rapid period of time, it could be anthrax spores. Most white powders, even if they are fairly soluble in water, will not rapidly dissolve.

Detection in the Host Organism

Along with monitoring for the physical symptoms described in the previous chapter, three methods for anthrax detection in the host organism are commonly used. The first method involves taking a blood sample and culturing it until anthrax can be positively identified. This method is accurate but often requires a patient who is already exhibiting symptoms. A second method is to use antibodies that stick to bacterial proteins in the blood. Finally, for hosts that are suspected to have been exposed to anthrax but are not exhibiting any symptoms, wipe/swab samples collected from the nasal passages, face, neck, hands or arms can be used to determine if anthrax spores are present. As discussed above, modern detection methods also include the creation of a large number of diluted samples for concurrent detection and testing. This method is especially useful for testing many different kinds of antibiotics and other therapies without losing any valuable time that the patient may require to survive.