The public health service in Peru attempts to introduce innovations to villagers to improve their health and lengthen their lives.  This change agency encourages people to install latrines, to burn garbage daily, to control house flies, to report cases of infectious diseases, and to boil drinking water.  These innovations involve major changes in thinking and behavior for Peruvian villagers, who do not understand the relationship of sanitation to illness.  Water boiling is an especially important health practice for villagers in Peru.  Unless they boil their drinking water, patients who are cured of infectious diseases in village medical clinics often return within a month to be treated again for the same disease. 

A two-year water boiling campaign conducted in Los Molinas, a peasant village of 200 families in the coastal region of Peru, persuaded only eleven housewives to boil water.  From the viewpoint of the public health agency, the local health worker, Nelida, had a simple task:  to persuade the housewives of Los Molinas to add water boiling to their pattern of daily behavior.  Even with the aid of a medical doctor, who gave public talks on water boiling before the campaign, Nelida’s diffusion campaign failed.  To understand why, we need to take a closer look at the culture, the local environment, and the individuals in Los Molinas. 

Most residents of Los Molinas are peasants who work as field hands on local plantations.  Water is carried by can, pail, gourd, or cask.  The three sources of water in Los Molinas include a seasonal irrigation ditch close to the village, a spring more than a mile away from the village, and a public well whose water most villagers dislike.  All three sources are subject to pollution at all times and show contamination whenever tested.  Of the three sources, the irrigation ditch is the most commonly used.  It is closer to most homes, and the villagers like its taste.

Although it is not feasible for the village to install a sanitary water system, the incidence of typhoid and other water-borne diseases could be greatly reduced by boiling the water before it is consumed.  During her two-year campaign in Los Molinas, Nelida made several visits to every home in the village but devoted especially intensive efforts to twenty-one families.  She visited each of these selected families between fifteen and twenty-five times; eleven of these families now boil their water regularly.

What kinds of persons do these numbers represent?  We describe three village housewives – one who boils water to obey custom, one who was persuaded to boil water by the health worker, and one of the many who rejected the innovation – in order to add further insight into the process of diffusion.

Mrs. A:  Custom-Oriented Adopter.  Mrs. A is about forty and suffers from a sinus infection.  The Los Molinas villagers call her a “sickly one.”  Each morning, Mrs. A boils a potful of water and uses it throughout the day.  She has no understanding of germ theory, as explained by Nelida; her motivation for water boiling is a complex local custom of “hot” and “cold” distinctions.  The basic principle of this belief system is that all foods, liquids, medicines, and other objects are inherently hot or cold, quite apart from their actual temperature.  In essence, hot-cold distinctions serve as a series of avoidances and approaches in such behavior as pregnancy, child-rearing, and the health-illness system. 

Boiled water and illness are closely linked in the norms of Los Molinas; by custom, only the ill use cooked, or “hot” water.  Once an individual becomes ill, it is unthinkable to eat pork (very cold) or drink brandy (very hot).  Extremes of hot and cold must be avoided by the sick; therefore, raw water, which is perceived to be very cold, must be boiled to make it appropriate to consume. 

Villagers learn from early childhood to dislike boiled water.  Most can tolerate cooked water only if a flavoring, such as sugar, cinnamon, lemon, or herbs, is added.  Mrs. A likes a dash of cinnamon in her drinking water.  The village belief system involves no notion of bacteriorological contamination of water.  By tradition, boiling is aimed at eliminating the “cold” quality of unboiled water, not the harmful bacteria.  Mrs. A drinks boiled water in obedience to local norms, because perceives herself as ill.

Mrs. B:  Persuaded Adopter.  The B family came to Los Molinas a generation ago, but they are still strongly oriented toward their birthplace in the Andes Mountains.  Mrs. B worries about lowland diseases that she feels infest the village.  It is partly because of this anxiety that the change agent, Nelida, was able to convince Mrs. B to boil water.

Nelida is a friendly authority to Mrs. B (rather than a “dirt inspector” as she is seen by other housewives), who imparts useful knowledge and brings protection.  Mrs. B not only boils water but also has installed a latrine and has sent her youngest child to the health center for a checkup.

Mrs. B is marked as an outsider in the community of Los Molinas by her highland hairdo and stumbling Spanish.  She will never achieve more than marginal social acceptance in the village.  Because the community is not an important reference group to her, Mrs. B deviates from village norms on health innovations.  With nothing to lose socially, Mrs. B gains in personal security by heeding Nelida’s advice.  Mrs. B’s practice of boiling water has no effect on her marginal status.  She is grateful to Nelida for teaching her how to neutralize the danger of contaminated water, which she perceives as a lowland peril. 

Mrs. C:  Rejector.  This housewife represents the majority of Los Molinas families who were not persuaded by the efforts of the change agents during their two-year water-boiling campaign.  In spite of Nelida’s repeated explanations, Mrs. C does not understand germ theory.  How, she argues, can microbes survive in water that would drown people?  Are they fish?  If germs are so small that they cannot be seen or felt, how can they hurt a grown person?  There are enough real threats in the world to worry about – poverty and hunger – without bothering about tiny animals one cannot see, hear, touch, or smell.  Mrs. C’s allegiance to traditional village norms is at odds with the boiling of water.  A firm believer in the hot-cold superstition, she feels that only the sick must drink boiled water.