Hygiene and Environmental Issues (Introduction)

Since the very beginning, sustenance and survival have been the two fundamental concerns of humankind. Natural disasters and afflictions of disease exposed man’s vulnerability to the forces of nature which necessitated a greater awareness of the natural environment. In the words of the celebrated physician and anatomist, Sir William Osler, “That man can interrogate as well as observe nature was a lesson slowly learned in his evolution”.^[1] Examination of health conditions and disease patterns in diverse ecological regions gradually helped to develop an understanding of the linkages between disease and environmental conditions, and the complex interactions between man and the natural conditions. As the well-being, prosperity and happiness of an individual depended on the condition of health, it became all the more important to examine the conditions that prevent any somatic and psychological maladies. The scope of Āyurveda, as defined by Dhanvantari to his students, is not only to cure the diseased but also to maintain the well-being of the healthy (svasthasya rakṣaṇaṃ).^[2] This statement underlines the importance of preventive medicine in the ancient medical science and its importance was recognised from early times. The Atharvaveda is replete with prayers, charms and incantations that offer protection from disease and calamities to humans and animals. The ancient Greeks, too, developed the physiocratic school of thought, realizing that maintaining good health and fighting illness depend on natural causes and that health and disease cannot be dissociated from particular physical and social environments nor from human behaviour.^[3]

In this chapter, we have looked at the disease-environment complex in the context of seasonal changes and their impact, the hypothesis regarding the occurrence of epidemics and the measures of counteraction, and the notion of hygiene. The concept of hygiene is central to preventive medicine. There is also much interest in prophylaxis in the classical medical texts which is more in the nature of dietary and lifestyle measures. We have also looked at the some measures of caution that have been recommended for the maintenance of health and well-being.

Āyurveda attaches much importance to the concept of kāla or time whose inexorable march impacts the entire universe. A hymn in the Atharvaveda is dedicated to the thousand eyed (sahasrākṣo), undecaying (ajaro) and prolific (bhūriretāḥ) deity, Kāla.^[4] All creatures in the world, including Prajāpati, are his creation.^[5] He possesses all the powers of sustaining, protecting and even destroying the universe. This notion finds resonance in our Saṃhitās.

In course of a discussion on the origin of man and disease, Bhikṣu Ātreya declares that living beings as well as their diseases are caused by kāla (time); the whole universe is conditioned by kāla and it is the causative factor of all.

kālajastveva puruṣaḥkālajāstasya cāmāyāḥ.
jagat kālavaśaṃ sarve kālaḥ kāraṇam.^[6]

In saying, “Time is the cause of diseases”, he perhaps meant that seasonal changes cause diseases.^[7] The notion of time acquires significance in medical science for its variations have an effect on the environmental conditions as well as on living beings. These variations brought about by time (kālakṛta) occur in a regular pattern, that is to say, diurnally, fortnightly, monthly, seasonally, solstitially and yearly. The rhythmical cycle of solar and lunar phases, variations in the atmospheric conditions, such as temperature, wind and precipitation are the natural causes of the accumulation, aggravation and subsidence of the doṣas.^[8] The human body is composed of the pañcamahābhūtas (the five elements of earth, water, fire, air and ether) and so are the food articles and medicinal substances. As Caraka states, all matter in the universe is constituted of five elements or mahābhūtas (sarvaṃ dravyaṃ pāñcabhautika)^[9]. Aridity or humidity, heat (temperature), wind patterns affect the potency (vīrya) of plants, the properties of water and soil, as well as the digestive ability of an individual.

The accumulation or subsidence of a particular doṣa is observed in a particular season. In the Gopatha Brāhmaṇa (II.1.19) we have a statement that sickness is particularly prevalent at the conjunction of the seasons: ṛtusandhiṣu ve vyādhirjāyate.^[10] The Atharvaveda notes that takman is a fever that occurs throughout the year; but the epidemic of this fever is at a high level in the rainy season, summer and autumn (V.22.13) and endures through autumn.^[11]

Treatment in Āyurveda is essentially the restoration of the equilibrium of the doṣas which is initiated after consideration of several factors. Appropriateness of time with respect to the season or kāla is one of the four aspects of treatment; the other three are vyādhī (disease), auṣadha (medicines) and kriyā (surgical and non-surgical procedures).^[12] It becomes, therefore, imperative to understand the how the cyclical changes of time affect the physiology of living beings. In Āyurveda, the year is divided into six seasons on the basis of the appropriate time for the administration of the elimination therapies. The seasons are:^[13]

Prāvṛṣ/Early Rainy corresponds to the months of Āṣāḍha and Śrāvaṇa

Varṣā/ Rainy corresponds to the months of Bhādrapada and Aśvina

Śarat/ Autumn corresponds to the months of Kārttika and Mārghaśīrṣa

Hemanta/ Winter corresponds to the months of Pauṣa and Māgha

Vasanta/Spring corresponds to the months of Phālguna and Chaitra

Grīṣma/Summer corresponds to the months of Vaiśākha and Jyeṣṭha^[14]

The year is divided into two major periods based on the sun’s position that has its impact on atmospheric conditions of heat and moisture. The northward movement of the sun (uttarāyana) is the period of dehydration (ādāna kāla) that corresponds to the seasons of late winter, spring and summer. The strong winds and the sunrays absorb the moisture from the air which enhances those savors (rasas) in drugs that have a drying effect–bitter (tikta), astringent (kaṣāya) and pungent (kaṭu). The sun’s southward movement is the period of hydration (visarga kāla) that corresponds to the seasons of the rains, autumn and early winter. With the onset of the rains, the sunrays lose their strength and there is increased humidity in the atmosphere. This, in turn, enhances the sour, salty and sweet savors (tastes). These changes affect the digestive ability, the doṣas and the general state of health.^[15]

It is necessary to keep in mind that the properties of drugs, particularly the savors or tastes (rasas), are modified by the atmospheric conditions. Each of the six rasas manifest the properties of one or two mahābhūtas. Thus, the sweet taste (madhura) is dominated by jala, sour (amla) by pṛthvī and agni, and so on.^[16]

Every season, is therefore, associated with the buildup of some doṣa. During the rainy season, plants are tender and of low potency, and water contains impurities. There is excessive moisture in the air and earth, chill in the wind and the body remains over hydrated. In such conditions as metabolism is weakened, food and water are not properly digested which leads to accumulation of pitta. However, when the rain-bearing clouds clear up and it gets drier in autumn, the accumulated pitta is liquefied which causes paittika diseases.^[17]

As the weather changes, the mild sun rays and frosty winds herald the onset of winter. Plants attain maturity and potency, while water becomes pure, bland and heavy. Digestion shows improvement, but as vegetal matter is essentially oily, cold, heavy and sticky in nature in this season, śleṣman/kapha gets accumulated Its effects are felt in spring when metabolism is low, the phlegm dissolves and the body suffers from diseases of the vitiated śleṣman.^[18]

The scorching summer sun draws the moisture of living matter, rendering plants and water less potent, dry and very light. Their ingestion leads to accumulation of vāta. When the season of prāvṛs ushers in the rains, the cooler air and increased moisture levels of the earth and the body, excites the vāta that produces vāta related illnesses.^[19] Thus, the accumulation, aggravation and subsidence of doṣika diseases follow a seasonal pattern.

The correlation of seasonal variations on the human body may be summarized in the following manner:

Atmospheric conditions–heat, wind and precipitation
                            ↓ affect
Properties of plants and water and human digestive power
                            ↓ affect
                          The doṣas
                        ↓ that cause
Disturbance of equilibrium of the doṣas
                 ↓ leading to Diseases

Though the affected doṣas subside naturally with the changing seasons, they need to be medically eliminated before the diseases become deep-rooted according to the following rule:^[20]

State of the Doṣas	Vāta	Pitta	Kapha
Accumulation /saṃcaya	Summer/ grīṣma	Rainy/varṣā	Winter/ hemanta
Aggravation /prakopa	Rainy/varṣā	Autumn/ śarat	Spring/vasanta
Alleviation/ natural subsidence /praśama	Autumn/ śarat	Spring/ vasanta	Summer/ grīṣma
Elimination by clinical methods	Early Rainy/prāvṛṣ	Autumn/ śarat	Spring/vasanta

In fact, the pattern of accumulation, aggravation and subsidence of the doṣas is not just seasonal, but quotidian as well. The forenoon resembles the features of spring, the noon of summer, the afternoon of early rainy season, the dusk of rainy season, the midnight of autumn, and the dawn of winter.^[21] The variations in temperature and other atmospheric conditions during the day and the night, account for the doṣika changes.

Thus, the climatic conditions and diurnal variations in the aggravation of the three doṣas would follow this pattern:

Vāta—in the cold and the rainy seasons, during cloudy days and in the presence of strong winds; at dawn, and during the last part of the day;^[22]

Pitta—in summer and autumn; at noon and midnight;^[23]

Kapha—in winter and spring; in the first part of the day; and the first part of the night.^[24]

The elimination of the aggravated doṣas at the appropriate time is necessary to prevent their progression to a further stage of pathogenesis when they become more harmful. Hence, the doṣas need to be eliminated at the stage of accumulation itself.^[25]

The seasonal factor had also to be taken into consideration before initiating medical intervention. It is emphasised that treatment must be carried out at the appropriate time. For instance -cold has to be counteracted in the cold season and heat in the hot season. Treatment done before the appropriate time or after such time has lapsed is not successful even in otherwise curable cases.^[26] The disease is easily curable if certain factors in the patient and his environment are contrary to it, such as the place (deśaviparita), season (ṛtuviparita), etc.^[27] Thus, if a vātika disease occurs in autumn, paiitika in winter or kaphaja in summer, then these are easily cured.^[28] It is also an important factor in procedures such as in cauterization and even in dressing of wounds. Thermal cauterization (agnikarma) is forbidden in autumn and summer. Nonetheless, it may be carried out in these two seasons during an emergency situation, with the provision of appropriate cooling measures.^[29] In late autumn, winter and spring, it requires change on every third day; while in the early autumn, summer and rainy seasons, the change is required every second day.^[30] Weather conditions need to be taken into account while conducting blood-letting procedure as the quantity of blood outflow depends on weather conditions, especially the day temperature. Bad weather, excessive cold, intense heat and draughts of wind can reduce or increase the flow of blood.^[31]

Kāla or the season is an important aspect of therapeutics that the physician should always keep in view along with other factors, such as the disease, habits of the individual, the physique, digestive capacity as well as the locale (deśa).^[32] Physical type is related to the environment by the physicians, and in turn, to the type of diseases generally encountered in a particular locale. In the medical texts we come across three types of deśa or ecological areas - ānūpa (swamp), jāṅgala (arid) and sādhāraṇa (intermediary type).

Ānupa land is characterised by water in abundance, undulations in the terrain, heavy rainfall, and where rivers and dense vegetation abound. The wind is mild and cool, and hills and trees numerous. People have soft, delicate and muscular body build, and diseases of kapha and vāta are common.

In jāṅgala deśa, the terrain is level like the sky, trees are thorny, few and far between, rain is scanty, and there is little water in the fountains and wells. The winds are hot and turbulent, hills are sparse and low and the people usually have firm and slender body build. Diseases of vāta and pitta are common here. Features of both types of terrain are to be found in sādhāraṇa deśa.^[33] Its name is derived from its features as the cold, the rains, the heat and the winds are moderate, and the doṣas more or less are in equilibrium.^[34] This a region in between, neither too wet nor too dry, the dry tropical forest of sparsely scattered trees that lose their leaves in the summer.^[35]

The observations of the ancient physician on the susceptibility of an environmental type to certain kinds of diseases helped him to understand how doṣas behave in particular ecological conditions, and in which conditions the disturbed doṣas can be pacified. Thus, it is understood that the doṣas accumulated in a particular locale do not become virulent when they get aggravated in some other locale which is not suitable for those doṣas, just as aquatic animals lose their strength when they are out of their environment (water)^[36] In other words, paittika diseases would be more easily pacified in a wet region, and so on. As Zimmerman comments, this knowledge was valuable for the prognosis of disease.

In India, as in Greece, anatomy and physiology were quasi-existent, and the medical practitioner had no truly biological knowledge on which to base his actions.

“What pathology depended on, instead, was what the Hippocratics called prognosis, the science of the course taken by illnesses and of the signs that herald accidents, crises, and solutions.”^[37]

The partial knowledge of anatomy and physiology prevented him from studying the affected parts to make a local diagnosis.

Therefore, Zimmerman argues the physician relied more on prognosis taking into consideration the general conditions of life: climate, seasons, customs and postures.

“His knowledge of the patient’s environment, including the flora and fauna, enabled the doctor to anticipate the course of disease and to take action on it.”^[38]

Footnotes and references:

[1]:

I. Asimov and J.A. Shulman, Issac Asimov’s Book of Science and Nature Quotations, New York, 1998, p. 174.

[2]:

Suśruta Saṃhitā Sūtrasthāna 1.14.

[3]:

Y. Tountas, “The Historical Origins of the Basic Concepts of Health Promotion and Education: the Role of Ancient Greek Philosophy and Medicine” in Health Promotion International, 2009, Vol. 24(2), pp.185-92. Doi: 10.1093/heapro/dap006 (Accessed on 21.5.2013).

[4]:

Atharvaveda XIX.53.1.

[5]:

Atharvaveda XIX.53.10.

[6]:

Caraka Saṃhitā Sūtrasthāna 25.25.

[7]:

V.W. Karambelkar, The Atharva-Veda and the Āyur-Veda, p.75.

[8]:

Suśruta Saṃhitā Sūtrasthāna 1.33-34.

[9]:

Caraka Saṃhitā Sūtrasthāna 26.10.

[10]:

V.W. Karambelkar, The Atharva-Veda and the Āyur-Veda, p.76.

[11]:

V.W. Karambelkar, The Atharva-Veda and the Āyur-Veda, p.76.

[12]:

Suśruta Saṃhitā Sūtrasthāna 1.38.

[13]:

Caraka Saṃhitā Vimānasthāna 8.125; Suśruta Saṃhitā Sūtrasthāna 6.10.

[14]:

A slight calendrical variation occurs in Caraka Saṃhitā Sūtrasthāna 6.4 where instead of two phases of the rainy season, winter is divided into hemanta (early) and i ira (late) phases.

[15]:

Caraka Saṃhitā Sūtrasthāna 6.4-7.

[16]:

Caraka Saṃhitā Sūtrasthāna 26.40.

[17]:

Suśruta Saṃhitā Sūtrasthāna 6.11a

[18]:

Suśruta Saṃhitā Sūtrasthāna 6.11b.

[19]:

Suśruta Saṃhitā Sūtrasthāna 6.11c.

[20]:

Suśruta Saṃhitā Sūtrasthāna 6.12-13, 38.

[21]:

Suśruta Saṃhitā Sūtrasthāna 6.14.

[22]:

Suśruta Saṃhitā Sūtrasthāna 21.20.

[23]:

Suśruta Saṃhitā Sūtrasthāna 21.22.

[24]:

Suśruta Saṃhitā Sūtrasthāna 21.24.

[25]:

Suśruta Saṃhitā Sūtrasthāna 21.37.

[26]:

Suśruta Saṃhitā Sūtrasthāna 35.21-22.

[27]:

Suśruta Saṃhitā Sūtrasthāna 35.46.

[28]:

Ḍalhaṇa’s commentary to Suśruta Saṃhitā Sūtrasthāna 35.46.

[29]:

Suśruta Saṃhitā Sūtrasthāna 12.5.

[30]:

Suśruta Saṃhitā Sūtrasthāna 5.39.

[31]:

Suśruta Saṃhitā Sūtrasthāna 14.27, 31.

[32]:

Suśruta Saṃhitā Sūtrasthāna 20.9.

[33]:

Suśruta Saṃhitā Sūtrasthāna 35.42.

[34]:

Suśruta Saṃhitā Sūtrasthāna 35.43.

[35]:

F. Zimmerman, The Jungle and the Aromas of the Meats: An Ecological Theme in Hindu Medicine, Delhi, Indian edition, 1999, p.7.

[36]:

Suśruta Saṃhitā Sūtrasthāna 35.43.

[37]:

F. Zimmerman, The Jungle and the Aromas of the Meats, p.20.

[38]:

F. Zimmerman, The Jungle and the Aromas of the Meats, p.20.