March 15 was the first Sunday that I can remember as an adult that I did not attend Mass. Frankly, it made my heart ache, watching the CatholicTV Mass online, seeing the host lifted up, but knowing I could not partake. The Eucharist is truly "the source and summit of the Christian life," the bread of angels that sustains us.

And yet, I strongly support Cardinal Sean for his difficult but wise decision. Without a doubt, he has saved many lives -- perhaps the life of your mother, your priest, or your doctor. This is not an overreaction: this is the reality being faced at hospitals around the world (most recently, in Italy and Spain).

My wife and I are physicians at a large academic hospital in Boston, where we work in urgent care and inpatient medicine.

We're also Catholics trying to practice our faith with dedication, including attending daily Mass as often as we can. The Mass is the center of our faith, our lives. The Mass is where God shows his love. Even when we're working nights or weekends, we always make it to Sunday Mass. So it pains us greatly to experience the suspension of public Masses. But it pains us more to see patients suffering and slowly dying of a disease, which is 100 percent preventable, because it's spread by human contact.

Simply emphasizing hand washing or covering your cough clearly isn't enough. Look at what's happening across the world. The number infected and the death toll are piling up. The stories coming from Italy are shocking: they've run out of ventilators (life-support breathing machines) and ICU beds in many hospitals: doctors must make gut-wrenching decisions on which patients get a chance to survive, and which are left to die (usually the older patients). The elderly and chronically ill are the most stricken, but even young doctors are dying. Hospitals worldwide are running out of equipment, including masks; staff have to reuse old ones to try to protect themselves. The numbers show that the rest of Europe -- and the USA -- is likely headed the same direction. The most effective strategy to slow the spread (and therefore overrunning hospitals and increasing death tolls) is strict social distancing/isolation.

If you knew that going to Mass this Sunday meant that quite possibly another 10 people would be hospitalized, and two people would die -- would it be worth it to you? What if one of those people was your grandmother, or your primary care physician, or your priest? Is that charity? What if the priest unwittingly infects others before he realizes he's infected? True heroism is not throwing oneself in harm's way in the name of piety, and, therefore, increase the suffering of others.

Many well-meaning, devout people posting on social media simply do not understand epidemiology or exponential growth. One person in a crowd can easily infect two or more people, each of whom could infect two or more: so it's no surprise we're seeing exponential growth across the world -- which has slowed down only in those countries which are imposing strict social distancing strategies. Although most people who catch the virus will be ok, perhaps 15 percent will be hospitalized, and 5 percent will need ICU beds (the numbers in Italy are much worse than these). Some experts estimate that we will need 1 million ventilators (the U.S. currently has approximately 160,000). Thus, if growth continues unchecked, very quickly, there will be no more ventilators for the patients who need them, and patients will die simply for lack of equipment (as is happening in Italy).

We Catholics have a long history of using the most advanced science to practice charity for others. Catholics started the first public hospitals (St. Basil the Great), founded the world's first universities (Bologna, Oxford), advanced the scientific method (Roger Bacon, OFM), discovered genetics (Father Gregor Mendel), and proposed the Big Bang Theory (Father Georges Lemaitre) -- during this time of crisis, it is not time for us to reject solid science.

With all due respect to those who never went to medical school: this is NOT the flu. This is clearly more contagious, and more serious: it much more often requires hospitalization and intubation (support on a breathing machine). There is a very real risk of U.S. hospitals being overwhelmed quite soon.

The best material weapon we have to fight this virus is social distancing. Cardinal Sean has wisely listened to the medical experts, and I am personally quite grateful.

We healthcare workers are on the front lines, with only masks, gloves, and thin plastic between us and patients coughing uncontrollably from a potentially fatal disease. I've worked in a number of harrowing hospitals in Africa, Asia, and South America, but this is unlike anything I've had to face. Honestly, it's frightening. Beyond the safety of me and my family, it's frightening to think about the many patients who will suffer and die. We must make the right decisions before it is too late.

Please, give those of us on the front lines a break: stay home as much as possible. Use this as a time for spiritual retreat. Participate in a streamed or televised Mass or adoration. Schedule set times to call friends or family to pray the rosary. Check in via phone or video chat with someone who may be lonely. There's a certain spiritual communion for all of us in this Lenten, isolated desert. Increased physical distance need not diminish our spiritual solidarity. Think of the saintly hermits, or remember that even St. Francis spent one Lent in total retreat -- without even the Mass. Offer up this sacrifice (it is a sacrifice, an act of charity), praying that this pandemic doesn't hit us as hard as it's predicted to. And then, when all of this has passed us (God willing), come back to Mass with renewed fervor (and reach out to your neighbor to do the same!).

Yes, I love the Mass, more than anything. But I prefer my priests alive -- so they'll still be here next year, serving us through Mass and other sacraments.

Please: the most charitable thing here is to keep yourself isolated.

And, on a few practical notes:

-- The Sacrament of Confession can be practiced at a distance (think of St. Damien of Molokai), perhaps even through a cracked window. There should be safe ways to arrange this with your priest (hopefully not involving either of you exposing themselves on public transport, sitting in a chair being re-used by many other people, etc.)

-- Practice social distance, and cancel or avoid gatherings (yes, even your annual St. Patrick's get-together; we've canceled ours. The memories and photos are not worth the risk of increasing death and suffering.)

-- Remember that the elderly and those with chronic medical conditions particularly need to distance themselves. This is not the time for your kid with a runny nose to visit grandma (particularly as kids infected with the virus often have few or no symptoms).

-- Practice frequent hand washing (and make sure you learn to do it correctly; e.g., don't use your clean hand to turn off a faucet handle you touched with your dirty hand).

-- Alcohol-based hand sanitizers probably work fine, too, but unfortunately hoarders seem to have taken it all.

-- Avoid touching your face, especially after touching high-touch surfaces like elevator buttons, door handles, etc.

-- If you are coughing/have a fever, please stay home and call your doctor. Most cases can be managed at home, and we'd prefer you not cough on your Uber driver or MBTA neighbors.

Stay healthy, and please pray for us and our patients. There will be Calvary before there is Easter.

THOMAS HEYNE, M.D., M.ST. IS AN ATTENDING PHYSICIAN AT MASSACHUSETTS GENERAL HOSPITAL, AND AN INSTRUCTOR AT HARVARD MEDICAL SCHOOL. THE OPINIONS EXPRESSED HERE ARE HIS OWN.