In response to my last post on fears that shaking hands and sharing a common communion cup just might increase the chances of infection during flu season, reader Garrett Brown pointed us to an article by Anne LaGrange Loving, a professor of microbiology.

Loving shares the results of two studies that she conducted. The first pitted the process of intinction -- in which the wafer or bread is dipped into wine and distributed to parishioners -- against the more pedestrian process of people lining up and taking sips out of the same cup.

The one time I visited an Orthodox church, intinction was the mode of communion. The priest dumped a bunch of bread squares into a big chalice of wine and fished them out with a ladle to place them on people's tongues. But I digress.

The intinction study found what one would might expect -- that this variation on the common cup transmits less bacteria rather than no bacteria. Loving explains that as a member of 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," so she had a good idea of what she would find in advance.

But Loving was curious about the rates of infection for those who drink out of a common cup vs. those who don't, and so she conducted another test. Here the results should cause some brows to furrow. The results of a ten-week survey of 681 people revealed essentially no difference in reported illness between those two groups. Those who supped from the chalice weekly or even daily were no more likely to get sick than those who got drunk the night before and slept in Sunday morning.

Now, it is entirely possible that Loving's methodology was flawed. At a glance, I'd say that different groups might have reasons to report that they felt "sick" at varying rates. While the survey data may be useful, I would place a lot more trust in it if they had taken weekly throat cultures or similar, more objective, markers.

Still, the piece is well worth the price of admission. We learn about the various strategies by Christians who share a common cup to minimize the risk of infection, including using wine with higher alcohol content, coming up with crazy compartmentalization schemes, or (for the priests) wiping down the chalice with linen that's been soaked in vodka.

There's also an interesting inference from Renaissance art that I'll leave you with:

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.

[A footnote: Yeah, I know what you're thinking. I thought that Loving's name practically screamed hoax but it turns out she's legit -- I think. There really is a Felician College, and one "Ann Loving" is listed as a professor emeritus in the directory. The journal that the article is said to have appeared in really does exist, though the archives do not go back as far as this particular issue. Same goes for the Journal of Environmental Health.]