Melanized fungi and military medical operations in the nuclear environment.

Abstract

INTRODUCTION The ability to conduct military operations in a nuclear environment will require an understanding of the medical threats posed by nuclear weapons and the development of tactics and techniques designed to mitigate them. This will be a difficult task given that we have no recent experience upon which to base doctrine. Experience is of paramount importance in the development of medical doctrine, as it provides the raw material from which medical planners determine infrastructure configuration, identify support requirements, and program the disposition of clinical resources. Where experience is lacking, both animal and in vitro studies have been utilized to provide data concerning the medical effects of nuclear weapons. Significantly, there has never been a systematic study of the microbiological aspects of nuclear war and consequently there is only a paucity of guidance available to military medical personnel regarding the role of the microbiology laboratory in the nuclear theater of operations and the development of the assets necessary for the production of an antimicrobial cache relevant to the nuclear environment. With reference to the study of the medical effects of nuclear war, the field of mycology is arguably the most neglected subdiscipline of microbiology. This omission is fallacious given that there are well over 100,000 species of fungi and that fungi have been found to occupy almost every environmental niche on the planet. In addition, invasive fungal infections resulting from combat-related trauma has recently been recognized as a significant cause of morbidity and mortality among military personnel who were injured during the Global War on terrorism. Previous research has revealed that certain categories of fungi (melanized or dematiacious fungi) are able to survive and thrive in an environment characterized by high levels of ionizing radiation. It is speculated that this capability may have enabled melanized fungi to survive the high levels of radiation present at the beginning of the cretaceous period when many other classes of organism perished. Previous studies have also shown that whole-body irradiation can lead to deficiencies in hematopoiesis resulting in a general state of immunosuppression and an increased susceptibility to infection by both endogenous and exogenous flora. Hematopoietic deficiency may also result in an increase in bacterial–fungal coinfection. This is concerning given that recent research has shown that infections due to both bacteria and fungi are often synergistic, difficult to treat, and associated with an increase in morbidity and mortality. From the military medical perspective, it is important to understand the interactions between bacteria and melanized fungi in the context of radiation exposure. Understanding these interactions will be necessary in order to assess and mitigate the threat that these organisms pose to military operations in a nuclear environment. In addition, understanding these interactions will enable military commanders and medical planners to program the proper distribution of resources and ensure that the appropriate diagnostic and treatment capabilities are available in the theater of operations.