This is SARS CoV-2. It belongs to the family of coronaviruses, named for crownlike spikeson their surfaces. SARS CoV-2 can cause COVID-19,a contagious viral infectionthat attacks primarily your throat and lungs. What actually happens in your bodywhen you contract the coronavirus?What exactly causes your bodyto develop pneumonia?And how would a vaccine work?The coronavirus must infect living cellsin order to reproduce. Let’s have a closer look. Inside the virus,genetic material contains the informationto make more copies of itself. A protein shell provides a hard protectiveenclosure for the genetic material as the virus travels betweenthe people it infects. An outer envelope allows the virusto infect cells by merging withthe cell’s outer membrane. Projecting from the envelope are spikes of protein molecules. Both a typical influenza virus andthe new coronavirus use their spikeslike a key to get inside a cell in your body,where it takes over its internal machinery,repurposing it to build the componentsof new viruses. When an infected person talks, coughs or sneezes,droplets carrying the virus may landin your mouth or noseand then move into your lungs. Once inside your body,the virus comes into contactwith cells in your throat, nose or lungs. One spike on the virusinserts into a receptor moleculeon your healthy cell membranelike a key in a lock. This action allows the virus to get inside your cell. A typical flu virus would travelinside a sackmade from your cell membraneto your cell’s nucleusthat where your cell housesall its genetic material. The coronavirus, on the other hand,doesn’t need to enter the host cell nucleus. It can directly access parts of the host cell,called Ribosomes. Ribosomes use genetic information from the virus to make viral proteins,such as the spikes on the virus’ surface. A packaging structure in your cell then carries the spikes in vesicles,which merge with your cell’souter layer, the cell membrane. All the parts needed to create a new virusgather just beneath your cell’s membrane. Then a new virus begins to butt offfrom the cell’s membrane. For this, we’ll have to look into your lungs. Each lung has separate sections,called lobes. Normally, as you breathe, air moves freelythrough your trachea, or windpipe, then through large tubes, called bronchi,through smaller tubes, called bronchioles,and finally into tiny sacs, called alveoli. Your airways and alveoliare flexible and springy. When you breathe in,each air sac inflates like a small balloon. And when you exhale, the sacs deflate. Small blood vessels, called capillaries,surround your alveoli. Oxygen from the air you breathepasses into your capillaries,then carbon dioxide from your bodypasses out of your capillariesinto your alveoli so that your lungscan get rid of it when you exhale. Your airways catch most germsin the mucus that lines your trachea,bronchi, and bronchioles. In a healthy body, hair-like cilia lining the tubesconstantly push the mucus and germsout of your airways,where you may expel them by coughing. Normally, cells of your immune system attack viruses and germs thatmake it past your mucus and ciliaand enter your alveoli. However, if your immune system is weakenedlike in the case of a coronavirus infection,the virus can overwhelm your immune cellsand your bronchioles and alveolibecome inflamed your immune system attacksthe multiplying viruses. The inflammation can causeyour alveoli to fill with fluid,making it difficult for your bodyto get the oxygen it needs. You could develop lobar pneumonia,where one lobe of your lungs is affected,or you could have bronchopneumoniathat affects many areas of both lungs. Pneumonia may cause. . . difficulty breathingchest paincoughingfever and chillsconfusionheadachemuscle painand fatigue. It can also lead tomore serious complications:respiratory failure occurs when your breathing becomes so difficultthat you need a machine calleda ventilator to help you breathe. These are the machines that save livesand medical device companies currentlyramp up production for. Whether you would developthese symptoms depends on a lot of factors, such asyour age and whether youalready have an existing condition. While all this all sounds scary,the push to develop a coronavirus vaccineis moving at high speed. Studies of other coronaviruseslead most researchers to assume thatpeople who have recovered froma SARS-CoV-2 infection could be protectedfrom reinfection for a period of time. But that assumption needs to be backedby empirical evidence andsome studies suggest otherwise. There are several different approachesfor a potential vaccineagainst the coronavirus. The basic idea is thatyou would get a shot that containsfaint versions of the virus. The vaccine would expose your bodyto the virus that is too weak to cause infection but just strong enoughto stimulate an immune response. Within a few weeks,cells in your immune system wouldmake markers called antibodies, which would be specific foronly the coronavirus or specificallyits spike protein. Antibodies then attach to the virus and prevent it from attaching to your cells. Your immune system then respondsto signals from the antibodiesby consuming and destroyingthe clumps of viruses. If you then catch the real virus at a later stage,your body would recognize and destroy it. In other words, your immune system is now primed. Collecting evidence onwhether this will be possible,safe and effectiveis part of what’s taking researchers so long to develop a vaccine. It is a race against time to develop a vaccine amid a pandemic. Each step in vaccine development usually takes months if not years. An Ebola vaccine broke recordsby being ready in five years. The hope here isto develop one for the new coronavirusin a record-breaking 12 to 18 months. While all this will take time,stay home if you canto protect the most vulnerable and don’t forget to wash your handsfor at least 20 seconds andas often as possible.