A microbiologist shows, through scientific studies, that receiving Holy Communion does not increase one's illness rate when compared to the general population which does not take communion.

The Christian sacrament of Holy Communion reenacts the Last Supper, at which Jesus Christ presided nearly 2,000 years ago. Today, many of the world's over 2 billion Christians consume consecrated bread and wine, some as often as twice daily.

Popular belief holds that Christ and his disciples shared a common cup of wine; so many Christian denominations use a common communion cup during the Holy Eucharist.

Concern about the possible spread of disease through shared communion cups dates back many years, with articles appearing in religious and scientific journals as far back as 1887. The potential hazards of this practice have been debated and investigated exhaustively. Christian leaders have attempted to quell fears of infectious diseases while imploring their parishioners to attend church and receive the sacraments. The scientific community has scrutinized the microbial aspects of virtually every aspect of the sacrament, testing the wine in the chalice, the chalice rims after people have sipped, the purificator cloths, the heavy metals used to make most chalices, unused wafers, and wafers that have been dipped in wine.

When reading through the literature, one sees that some of the diseases which concerned earlier investigators, such as syphilis and diphtheria, are for the most part preventable or curable today. Other "old" diseases, however, like tuberculosis, remain just as threatening to the general population. Individuals who are immuno-suppressed or immuno-compromised due to AIDS, chemotherapy, radiation therapy, or congenital disorders are especially vulnerable to infectious diseases.

Even the "average healthy individual" is more susceptible at some times than others, due to factors such as temporarily immuno-compromising infections or stress. AIDS, in particular, has caused the issue of the common cup to resurface with great intensity. Religious publications have been inundated with articles arguing the case for and against sharing the chalice. Most of these attempt to address the unreasonable AIDS-transmission phobia.

Alternatives to the common cup have evolved over the 2,000 years of Christianity. Leonardo DaVinci's "The Lord's Supper" depicts the disciples with separate cups of wine, indicating that this practice may have been customary during his lifetime.

Today, parishes throughout the world use a variety of methods for distributing the wine, including: the common cup; separate cups; individual communion spoons; special chalices from which many people can sip from separate compartments around the rim; intinction (where either the priest/pastor or the parishioner dips the wafer into the wine); and individually wrapped, sterile, disposable packs which contain a wafer and a small cup of wine.

Some churches use communion wine that is fortified with a higher alcohol content in an effort to eliminate pathogenic microbes. Others dip the purificator cloth into vodka for the same purpose. Chlorinated tap water that is used during the consecration may kill some bacteria, and the heavy metals from which many chalices are created exhibit antimicrobial activity.

Intinction Risk Study
In 1995, I performed a laboratory study on the microbial risks of intinction that was published in the Journal of Environmental Health (July-August 1995 issue). When I searched the literature for articles about the hygiene hazards associated with Holy Communion, I found that several religious and scientific articles stated that intinction is a "completely safe" alternative to sipping from the common communion cup.

However, I was unable to find any scientific study that investigated the microbial risks of intinction.

As a parishioner in a church where many members use intinction, I was able to observe that the fingers of the parishioners and ministers often dip into the wine during the process of intinction. Knowing that hands may harbor many pathogenic microbes, I was concerned.

I set up a carefully controlled laboratory investigation using volunteer parishioners and priests, communion wine, a communion chalice, and communion wafers. Participants were instructed not to wash their hands prior to the start of each series of tests, as parishioners typically would have been sitting in a Eucharist service for at least 30 minutes before the administration of the sacraments. During this time, fingertips may touch many potentially contaminating surfaces.

In addition, participants all shook or grasped the hands of between 2 and 10 people just prior to the start of the testing, to simulate the exchange of microbial organisms that occurs when parishioners offer each other the "Peace of the Lord."

During the simulated Eucharist services, samples were taken of participants' fingertips, the wine, the wafers before and after being dipped into the wine, and of the "dregs" of the wine that remained at the end. Bacterial cultures were performed on all of these samples.

The findings revealed that bacteria are indeed transferred into the wine when a person's fingertips are submerged, and these same microbes can then be absorbed onto the wafer of a subsequent participant, in a sponge-like fashion. Not surprisingly, some individuals in the study had small amounts of fecal and other potentially dangerous bacteria on their fingertips, and some of these were recovered from the chalice samplings.

However, the statistics in this study showed that although intinction is by no means completely microbe-free, it does seem to reduce the risk over that of sipping from a common communion cup.

Having completed this investigation, I realized that my findings could be added to the large pool of previous studies that all showed the same thing: Holy Communion is like any other activity in which humans have close contact — microbes are exchanged.

Increased Illness Study
I continued to question, however, why the Christians I knew did not seem to have excessive health problems. This led to my second study, which was published in the Journal of Environmental Health (July-August 1997).

This second investigation addressed the specific question raised more than a century ago, a question that laboratory studies, religious declarations, and the assertions of the lay public had failed to answer: Do Christians who receive Holy Communion get sick more often than those who do not receive, or than individuals who do not attend church?

The question was confronted using a survey tool that asked three basic questions: Have you attended church? Have your received the sacraments? Have you been sick?

Participants were enlisted through school, college, business, church, and neighborhood networks. All volunteers were accepted into the study, regardless of age, gender, general health, race, or religious affiliation. The survey tool included a demographic cover sheet followed by 10 weekly survey pages, each of which clearly identified the week in progress. Everyone was from the same geographic area (New Jersey), and everyone filled out the survey during the same 10 weeks. Thus, there should have been similar exposure to prevailing illnesses, weather conditions, and other environmental factors.

Once the surveys were returned, my colleague Dr. Lisa Wolf (a statistics genius) analyzed the results.

Participants were broken down into groups based on their church attendance patterns and their participation in the Holy Eucharist. There were 307 respondents who usually attended church and received the sacraments, 53 who usually attended and did not receive, 83 who sometimes attended and received, 27 who sometimes attended and did not receive, and 211 who never attended church during the 10 weeks.

Household categories were formed based on the numbers and ages of the individuals living in a respondent's home. The youngest participant was one year old; the oldest was 84.

In this epidemiological sampling of 681 individuals, no differences in illness rates were reported among those who received communion, those who attended but did not receive, and those who never attended church. This even held true for the participants who attended church and received the sacraments every single day during the 10 weeks.

An analysis of the data also revealed that households with children under the age of 12 reported more illness than households without children, which was not surprising.

From these findings it could be concluded that individuals who live with children are more likely to be ill than those who attend church and receive the sacraments as often as every day.

Although numerous studies (including my own on intinction) have demonstrated that microbes are transferred during Holy Communion, and that the potential for spread of disease during this ritual does exist, the survey study clearly illustrated that receiving Holy Communion as often as daily does not increase one's illness rate.

Anne LaGrange Loving is assistant professor of microbiology at Felician College, Lodi, New Jersey. This article was first published in Covalence, vol. 1, no. 1, January-February 1998, pp. 1, 4-5, and is used by permission from the author. Covalence is a bulletin of the Ecumenical Roundtable on Science, Technology, and the Church and is published by the Division for Ministry, ELCA. An extensive bibliography of articles from scientific, religious, news, and popular culture sources is available from Prof. Loving. For more information, contact Prof. Loving at lovinga@inet.felician.edu.