I think part of the problem here is that you are confusing existence with consciousness and reason with consciousness.

Deciding that we "exist" is something that philosophers have defined as thinking (Decartes) to the use of language (Heidegger). If there is one common thing to the human existence is that we have figured out that we are different because we can make a decision using reason to do or not to do something. We also are more aware of the passing of the seasons, planets, and other phenomena at a level beyond the instinctive (brain stem/lower brain) and can make decisions based upon that. Humans also have the ability to observe, take in knowledge and then make decisions based upon that information that fly in the face of instinct and continue to do so for succeeding moments without reverting to instinct. This ability is described as consciousness.

Everything in the universe is connected by the material that was present in the big bang and, I believe, by impetus from the Divine. Using your virus example, it is possible, at very high levels of meditation technique to energetically work with the virus and take it out of your body. Take A.R. Heaver for example. After suffering paralysis following a bi-plane accident in WWI he used esoteric techniques and experienced robust health until his 80s. Because everything is connected and has a level of consciousness that varies from ours (very high) to the lowest (single cell) you can tap into that consciousness and create great change. You can observe group consciousness as well. If I take a group of humans together and start talking to them about something and I can speak from a place of authority and convince them that I can speak on that topic then I can begin to convince them of a variety of things. I can even employ questions and talking amongst them as devices to advance my goals. Cultures where group consensus and agreement are paramount see this used every day as a way for society to move forward and to come to quick, culturally agreed solutions to problems. Many people have said that this group consciousness caused everything from the rise of Communism in Russia to the rise of National Socialism (NAZI) politics in Germany.

To say that there is no consciousness is to deny your own existence, your own awareness of what is happening around you, and to deny your connection with everything from the smallest of the small to the expanse that is the universe. It is all us and we are all it. Your computer has a kind of consciousness although its consciousness is limited. Your car has a kind of consciousness. Environments have consciousness through systems. Take the interstate for example. It has systems (signs, lanes, on ramps, off ramps, over passes, and barriers) to allow humans piloting cars to navigate the environment to achieve their transportation goals. To deny that consciousness is to deny the awareness of the engineers, the construction workers, the paint, the concrete, and the technology behind it that created it. You also deny the conscious decisions made by everyone that allows us to drive 55-75 mph without crashing into each other. If you work with objects you can being to understand them and their consciousness, their beingness, and their contribution and connectedness to the greater Whole. All of the universe is looking for wholeness and within each of us is that unique possibility. This is consciousness.