Biological Hazards

Travel to remote areas carries with it inherent risk dictated by the flora and fauna of the region. Regional public health concerns become the concern of the research team as well. Biological hazards can be defined as those hazards that pose a risk of infection to the individual. These biological risks may include viral, bacterial, parasitic, or fungal invasion of the body. Malaria, hantavirus, rabies, tetanus, poisonous plant exposure, and poisonous reptiles and insects are a few examples of the many biological hazards encountered in field-work. The possibility of contracting an endemic disease in a faraway land, then returning home with it without knowing the etiological possibilities, may delay diagnosis and treatment by physicians not familiar with illnesses uncommon to their local practice area.

Another important consideration is an accurate clinical history. The disorder one may be afflicted with may not have been the result of a biological hazard in some faraway land, but rather some condition they came into country with in the first place. Knowing your body's physiological response to biological insult is a good way to document and report your clinical history to a health-care professional.

When considering biological hazards, it is imperative to know the health risks associated with the country and the specific region of that country to which you plan to travel. Excellent references regarding the health risk status of various countries are the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO). Both these organizations maintain up-to-date information about endemic diseases and outbreaks of unique diseases in most countries around the world. Each member of the research team must be prepared by having a clear understanding of what biological stew he or she may be heading into.

Equally important for the team members, beyond researching the CDC and WHO information, is to consult their primary care physicians and a physician who specializes in tropical medicine. It is critical to make arrangements to see these physicians well in advance of the trip, as appointment schedules often need to be made months in advance. In addition, if immunizations are required, appropriate lead time is required for many immunizations to be effective. Common immunizations may include those for yellow fever, tetanus update, hepatitis A, typhoid, and others dictated by the destination. Commonly required medications may include those for malaria prevention and prophylactic treatment for altitude sickness. In addition, tropical medicine physicians will often prescribe appropriate antibiotics to be taken should a team member contract gastrointestinal infections.

Tropical medicine physicians will also be aware of any recent outbreaks in various global settings. While one of the authors was preparing for a recent trip to Papua New Guinea, an outbreak of Japanese encephalitis occurred, but the timing of the outbreak was such that immunization would have been ineffective. In addition, the physician suggested that the immunization carried risks that perhaps outweighed the risk of contracting the disease while in the country. With the information provided by the specialist in tropical medicine, the team members could make an educated decision about the biological hazard potential regarding that specific outbreak.

If your research organization, be it university based or private, conducts many out-of-country expeditions, it is suggested that a specific tropical medicine physician or group become familiar with your activities, travel locations, and the health profiles of your team. These physicians are often willing to be involved in pretravel orientation sessions with the team, which is particularly important when student assistants are members of the research team. Although not always the case, students will sometimes heed the advice of a tropical medicine professional before taking any advice their professors may give them.

Just as important as the preparatory immunizations and precautionary treatments, such as malaria prevention, is the need to know what the chances are for contracting a community-acquired disease in the destination country. A community-acquired disease is defined as a cluster of illnesses usually brought on by an infection contracted from the general public and its communities. These diseases can be viral, bacterial, fungal, protozoan, or parasitic in nature. Team members' knowledge of the risks of acquiring such community-acquired diseases as pneumonias, influenzas, tuberculosis, and sexually transmitted diseases (STDs) cannot be overstated. The methicillin-resistant Staphylococcus aureus (MRSA) is responsible for a serious community-acquired disease at the time of the writing of this book. It is included here as an example of the potentials and serious risks associated with community-acquired diseases.

The fundamental tenet for team members traveling to remote field sites or congested municipalities should be to know the environment. If, for example, there is a pathogenic fungal spore known to be endemic to a region, knowing the specific type of fungal infection, which can be contracted from inhalation of these specific fungal spores, is critical. Just knowing that there are potential fungal infections is incomplete information. Often, the remote fieldwork requires close contact with the soil in and around ancient tombs, stirring it up and increasing the potential for fungal spore introduction by inhalation. Even artifacts can be filled with shifting sand and dirt over the centuries, and when this soil is removed from a ceramic piece or brushed from the surface of textiles, the risk of the fungal spores becoming airborne is present.

When working in crypts or other subterranean environments, molds may well be present. In addition, molds may be present on the mummified remains themselves. Inhalation of mold spores may have different effects on different people; however, it is advised to wear a properly fitted filter-type mask when working in these settings. A surgical-type mask may not be enough to adequately filter out the spores. Surgical-type masks fit rather loosely, allowing the spores to bypass the filtering surface of the mask and are hence not recommended.

Knowing the environment includes not only knowing what diseases may be prevalent in a region but also how those diseases are spread. It is well known that mosquitoes are the vectors of malaria; similarly, there are many other diseases, and some have unique modes of transmission. For example, Chagas' disease is contracted by the blood-sucking reduviid vector known as the "kissing beetle," which defecates at the bite site, introducing the protozoan Trypanosoma cruzi into the host. Female sand flies found in moist soil, caves, forests, and rodent burrows can transmit forms of leishmaniasis. Again, it is beyond the scope of this book to list all the potential vector-disease relationships, but the importance of awareness of them on the part of all team members cannot be overstated. Preexpedition research and orientation are critical to the safety of the team.

Although it should go without saying, knowing the food and water quality in the region of the research is critical. It is foolhardy to believe that any source of water you encounter during your travels is safe and not worth the team's examination. Many parasitic infections arise from drinking contaminated water, in particular, Giardia lamblia, which is probably the most common cause of parasite-induced diarrhea and is introduced by the ingestion of environmentally resistant cystic forms from water, food, or from unwashed hands contaminated with fecal matter. Even water from the nicest hotels and restaurants is suspect. It is critical to plan ahead for the water and food needs of the team.

Finally, the microenvironment of the mummy itself must be considered. Many embalming chemicals were used and experimented with, resulting in mummified remains. Early medical mummies were embalmed with a variety of heavy metals, such as mercury, zinc, and arsenic. The French chemist, Jean Nicholas Gannal (1791-1852), first employed arsenic for embalming in the early to mid-19th century. Arsenic embalming found its way to North America toward the end of the Civil War, with many Union officers and enlisted men being embalmed with various arsenic solutions. At times, the embalming solution may have contained as much as 10 lb of arsenic per body! Arsenic embalming was also used on unclaimed bodies, which found their way to the sideshows of traveling carnivals during the late 19 th and well into the 20th centuries. Knowing the mummification chemistry is critical to the safety of the team members.

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