Do jungle boots stop jungle rot?

Abstract

To the Editor: Increasing numbers of people leave the UK each year on expeditions to tropical regions, sporting a variety of gear purchased on the advice gained from numerous sources. During their time in the jungle environment, they are at risk of suffering from tropical foot disorders that are capable of rendering its victims immobile, thus adversely affecting both the individuals affected and the expedition. This letter describes the incidence of foot problems in 26 adults during a 2-month expedition to Borneo in relation to the type of footwear worn. Until the 1960s, foot problems associated with the jungle environment were widely defined and given names such as “immersion foot,” “tropical jungle foot,” and “jungle rot.” These covered a multitude of symptoms, from dermatomyositis and pyoderma to abrasions.1.Whayne TF, DeBakey ME. Cold injury, ground type, in World War II. In: Adnot J, Lewis CW, eds. Immersion Foot Syndromes. Military Dermatology. Falls Church, VA: US Department of the Army; 1994:55–88. Available at: http://www.vnh.org/MilitaryDerm/Ch4.pdf. Accessed February 29, 2004.Google Scholar During the Vietnam War, research led to the more accurate terms warm water immersion foot, in which the soles become painful, white, and wrinkled, and tropical immersion foot, in which the ankles and dorsa of the feet become swollen and tender. This occurred after soldiers’ feet had been exposed to warm water (22°C–32°C) for more than 72 hours.2.Allen A.M. Taplin D. Tropical immersion foot.Lancet. 1973; 2: 1185-1189Abstract PubMed Scopus (38) Google Scholar While on a 2-month expedition in Sabah, Borneo, several expedition members succumbed to either warm water immersion foot or tropical immersion foot. All expedition members were subject to the same climatic conditions. Temperatures ranged between 29°C and 38°C, with humidity between 65% and 100%. Activities consisted of carrying loads weighing approximately 20 kg across primary and secondary jungle terrain. Small tributaries were frequently crossed, and the only time feet were dry was at night, while persons were asleep in hammocks.Tabled 1Incidence of foot problems Of the 26 members of the expedition, 14 wore army issue jungle combat boots, while 12 chose regular 2- to 3-season hill walking boots. The Table shows the incidence of foot problems in relation to the type of footwear worn. Expedition members developed mild, moderate, and severe forms of warm water immersion foot and tropical immersion foot. The severity of the problem was measured in terms of clinical appearance, treatment administered, and level of physical incapacity and thus is partially subjective. Chi-square tests showed a significantly reduced chance of developing any type of foot problem if jungle boots were worn (P = .004). In addition, not wearing jungle boots significantly increased the risk of a moderate or severe foot problem (P = .003, chi-square test). Although the author recognizes limitations regarding group size and clinical assessment, this remains an interesting observation that does not appear to have been previously reported in the medical literature. Army issue jungle boots are of single-layered leather/canvas construction, with built-in drainage vents, compared with 2- to 3-season hill walking boots, which are multilayered and designed to keep water out. The construction of hill walking boots means that once water is inside, it is prevented from draining. While on expedition, those with hill walking boots found it almost impossible to prevent their footwear from being waterlogged most of the time, and they had to keep their feet immersed in a “jacket” of warm water: a feature that has previously been described as “moon-boot foot syndrome.”3.Blogg H. Moon-boot foot syndrome.Br Med J. 1982; 285: 1774-1775Crossref PubMed Scopus (3) Google Scholar,4.Phillip R. Moon-boot foot syndrome.Br Med J. 1983; 286: 562Crossref Scopus (5) Google Scholar Although the feet of those wearing jungle boots were wet, proper drainage prevented this “jacket effect,” and when it was possible to keep feet dry for a day or two, their boots dried more quickly. In light of this observation and given the lack of available data regarding foot disease prevention,5.Adnot J, Lewis CW, eds. Immersion Foot Syndromes. Military Dermatology. Falls Church, VA: US Department of the Army; 1994. Available at: http://www.vnh.org/MilitaryDerm/Ch4.pdf. Accessed February 29, 2004.Google Scholar consideration should be given to a randomized study with greater scientific validity. In the meantime, however, expeditions to jungle environments would benefit from a strong recommendation in favor of jungle boots to reduce the risk of foot disease, suffering, and incapacity. The author thanks Jonathan Benger, MD, FRCS, FFAEM, for assistance with statistical analysis.