Military Hygiene and Hygiene in Emergency Situations - K.O. Pashka 2005

Fundamentals of organizing and conducting sanitary supervision and medical control over water supply for military personnel and the civilian population in field conditions
Physiological, hygienic, and epidemiological significance of water

Providing Water in emergency situations, alongside other life-support components, is a complex and critical challenge. It requires addressing issues related to the availability of suitable water sources, their degree of development, as well as the quantity and quality of the water.

Supplying military formations and affected populations with safe drinking water in the field is a crucial factor in preserving the health and combat readiness of personnel, as well as the efficiency of emergency response workers and civilians. This demands the extraction and transport of significant volumes of water to military units and groups of the population. Water is essential for meeting the body's physiological needs and plays a vital role in strengthening the health and physical conditioning of personnel. Without it, maintaining proper living and sanitary conditions—which is extremely important in the field to prevent various diseases—is impossible. Large quantities of water are also required for the sanitary Processing of troops (and the affected population), the decontamination and degassing of various objects and individuals, and for other technical purposes.

Water is one of the most vital elements of the biosphere. A human can survive without water for no more than 5–6 days. The body of an adult human consists on average of 65% water, a proportion that decreases with age. All biochemical reactions in The Human Body related to Digestion and the assimilation of nutrients take place in an aqueous medium. Water is an excellent solvent for various substances. Together with salts, it helps maintain a critical physiological constant of the Organism: osmotic pressure. Due to its low viscosity, its ability to dissolve various chemicals, and its capacity to form weak bonds with them, water serves as the primary component of Blood and acts as a transport medium. Furthermore, it forms The basis of the body's acid-base balance. All assimilation and excretion processes in the body also occur in an aqueous environment.

To meet physiological needs, a person requires 2.5–3.0 liters of water per day, and an equivalent amount is eliminated from the body. Water enters the human body through drinking and food. Along with water, many physiologically essential salts—including macro- and microelements such as calcium, magnesium, sodium, potassium, iodine, and fluorine—are ingested. During heavy labor, work in hot shops, or in the summer, water loss can increase to 8–10 liters.

The human body tolerates dehydration poorly. The loss of 1.0–1.5 liters of water already triggers a sensation of thirst. This is associated with The stimulation of specific areas in the Central Nervous system (the "thirst center") that regulate Water Balance and signal the need to replenish the body's fluid reserves. If water loss is not compensated, overall well-being deteriorates, physical performance drops, Water-Salt METABOLISM and thermotherapeutics are disrupted, and the body may overheat. Inadequate water consumption negatively affects the absorption of nutrients in the intestine. A water loss of 15–20% of body weight at air temperatures above 30 °C is fatal, while a loss of 25% is fatal regardless of Temperature. This represents the physiological significance of water.

The hygienic significance of water lies in its use for maintaining personal hygiene, cooking, washing dishes, doing laundry, cleaning premises, removing sewage through drainage systems, and watering streets and green spaces. Water helps improve living and recreational conditions and contributes to physical hardening. Landscaping, along with the creation of lakes, ponds, reservoirs, and fountains, improves the local microclimate. This is particularly important in southern regions, which experience high average annual temperatures and low air humidity.

The epidemiological significance of water is exceptionally important for humans. It largely depends on water supply conditions, the sanitary maintenance of populated areas, and the population's level of sanitary culture. Contaminated water can cause a range of gastrointestinal diseases, such as cholera, hepatitis A, typhoid fever, paratyphoid fevers, bacterial and

amebic dysentery, and acute infectious enteritis. In the USA and Western European countries, these diseases were a true scourge in the 19th century, manifesting as terrifying epidemics and claiming thousands of lives. In 1996, a major outbreak of El Tor cholera occurred in Manipur, India, sickening about 1,200 people. The cause of the epidemic was river water contaminated with wastewater from an upstream settlement.

One of the causes behind the emergence and spread of intestinal infections is the prolonged viability of health-hazardous microorganisms in an aqueous environment. For instance, Escherichia coli and the pathogens of typhoid fever can survive in water for up to 183 days, while those of dysentery and cholera can survive for up to 92 days.

Pathogens of gastrointestinal diseases transmitted via the fecal-oral route contaminate water when they enter bodies of water through human excrement and wastewater. In this regard, wastewater from infectious diseases hospitals and clinics is particularly dangerous. Water contamination also occurs due to the discharge of gray water from ships into water bodies, the pollution of riverbanks with sewage, the establishment of mass bathing and laundering sites, the seepage of latrine waste into groundwater, and the Introduction of pathogens into wells using contaminated buckets, etc.

Viruses transmitted through contaminated water can also cause human diseases. Currently, about 100 types of viruses present in human feces are known. They can persist in water for extended periods (up to 200 days). Furthermore, many of them are significantly more resistant to disinfectants than Bacteria. It has been noted that even very small doses of viruses can trigger acute intestinal infections in humans, which explains the widespread occurrence of waterborne hepatitis A epidemics.

Anthropozoonotic diseases (diseases shared by animals and humans) can also be transmitted through water. Among these are leptospirosis, tularemia, brucellosis, and Q fever, which can enter water bodies via the urine and feces of rodents, pigs, and cattle. Such infections most frequently result from drinking water from open reservoirs (rivers, lakes, ponds, aryks, irrigation canals) or from swallowing water while swimming. Leptospires can also enter the human body through mucous membranes and micro-INJURIES OF THE Skin.

In addition to pathogenic microbes, contaminated water can deliver Giardia cysts, Ascaris and whipworm eggs, hookworm larvae, Liver fluke cercariae, as well as guinea worm microfilariae and schistosome cercariae—which are common in hot countries and cause dracunculiasis and Schistosomiasis—into the human body.

The pathogens of several diseases develop not directly in water, but within aquatic hydrobionts such as Mollusks (schistosomes and other trematodes) or copepods (the guinea worm). Human infection can also occur through the consumption of inadequately treated raw water or unwashed fruits, greens, and vegetables.

Emergencies frequently disrupt the supply of safe drinking water to affected populations, which can trigger so-called waterborne epidemics.

Waterborne epidemics are always linked to the consumption of contaminated water from a specific source (such as a well or water mains). Such outbreaks are characterized by a sharp spike in infections, mass casualties among the population, and a slow decline toward the end of the epidemic period. The cause of the illness is always confirmed through laboratory analysis of water samples taken from the contaminated source. All of this is crucial when implementing Sanitary and anti-epidemic measures to prevent and eliminate waterborne outbreaks.