We can never say thank you enough for what you do, every day, even in normal times. Words fail for the extra effort so many have made when times are tough. During critical times like hurricanes or forest fires or tornadoes or floods or terrorist acts, the heroism of those in the path of danger stands out and they get their shot at glory. In pandemics, most every first responder and care giver is on the front lines and deserves a tribute to their daily grind, and yet since so many are suffering little thanks is given to any.
You chose your profession, accepting the risks that come with the job. Those who fight wildfires know that the wind can shift or suddenly increase at any time which might trap them. Firefighters know that there can be unexpected problems with air supplies or sudden invisible structural failures that can doom them at any moment. The police know that they can come up against a drug user out of their minds, a hardened criminal, a bad domestic situation, or a riot at any time that can all of a sudden drop their chances of finishing a shift to 0. And EMTs know that some perfectly sane driver can make a mistake under pressure and cause an accident with their vehicle or that they will be exposed to some pathogen no matter how careful they are to say nothing of having to work in a potentially dangerous location along side the fire fighters or police. Doctors, nurses, technicians, and aides along with all the ancillary staff that do cleaning, engineering, food preparation and administrative or clerical work in medical facilities also face risks of exposure on a normal basis and have to deal with occasional situations out of their control even if those situations might not be a risk to them. These are the risks they choose to take, and the training they receive is provided to minimize bad outcomes. But minimization is not elimination. They know and accept that every shift, every day.
In pandemics or other huge disasters, that risk is exacerbated by fatigue, and it just keeps going on day after day with no let up in sight for weeks. So for you, this day, we say thank you. You are in our prayers. I know that that may not mean much of anything to you, but it is there anyway.
May God's protection go with you to keep you safe through another second - through another minute - through another hour - and finally through another shift. May God's grace go with you so you can have compassion with your fellow workers and those you are serving. And may His grace go with you when you return home exhausted both physically and emotionally. Remember that your family or significant other needs you just like they need you every other day. But also know that they are even more aware of the risks you are facing and that they are dealing with the knowledge that they could be exposed to those same risks with which you are dealing which is less often the case on a normal day. May God give your friends and families protection and grace to help you deal with everything that you face. May He give you strength to do all you can do on your current shift. May He give you rest so that when the next shift comes you will be emotionally and physically strengthened to do all you need to do on that shift as well. May He give you the wisdom you need to make the decisions you must make due to lack of resources and time. May He give you emotional strength to live with those decisions. May He give you the humility to pray for His help and the faith to know that He can help and wants to help both you and those you serve make it through this and every other crisis.
Realize that there are limits on what you can do. Viruses are pernicious. While they can strike anyone, you aren't responsible for whatever particular condition in a patient's life causes them to call on you for help. You weren't responsible for their lifestyle that put them particularly at risk. You didn't force them to smoke, to eat to much, to do drugs... You didn't choose their parents which caused their genetics to combine in a particular way that put their respiration systems at greater risk than others. And you certainly didn't choose to have a new virus get loose with no immunity so everything is going wrong all at once everywhere around the world.
All you can do is the best you can. No country or hospital is ever really ready for everything to go wrong affecting so many in such a short period as a pandemic causes. You aren't responsible for the lack of protective gear. You aren't responsible for the lack of lifesaving equipment. You aren't responsible for the decisions to isolate (or the lack of those decisions from governments) or for how well people have followed that. You aren't responsible for the lives versus economic decisions that will be made in removing the isolation rules. You aren't responsible for the virus changing as time goes on. You aren't responsible for how long it takes to develop a vaccine or for whether or not that vaccine will be effective in dealing with a possibly changed virus. All you can do is be the best at your jobs that you can be for one more shift, one more week, one more month...
Be strong, and know that you have our thanks for all that you do in times like these, and even in normal times, even though you don't hear it often enough from those who haven't had to depend on you (nor frequently even those who do).