Why Corona Virus Spreads so Fast?

Abstract

Coronaviruses are a family of common viruses that\xa0affect mammals and birds and most of the time the\xa0strains caused are mild symptoms like a common\xa0cold, fever, cough, and runny nose. Given the historic\xa0records, there has been cases of diseases every once in\xa0a while with strain that were new and were\xa0particularly lethal – they could spread through the\xa0world quickly and with more concerning outcomes.\xa0Prior examples of such diseases would include the\xa0SARS epidemic which is not exactly the same as\xa0COVID-19 that we re experiencing but some of the\xa0same features apply in that it is a corona virus. It is a\xa0new strain that we have not experienced before and it s\xa0spreading very rapidly.\xa0It is empirically understood that our world contains\xa0wide range of different viruses and every day since our\xa0birth we come into contact with them but we do not\xa0develop symptoms because of what s called herd\xa0immunity. It means most of us have some level of\xa0recognition with our immune system to the common\xa0viruses which is why some of us still get sick with\xa0colds and influenza. These illnesses tend to not\xa0overtake our healthcare system because people don tget sick all at once and even if so at least they usually\xa0do not get sick to a concerning level (easily treatable).\xa0The case is different when a new virus such as the one\xa0causing COVID-19 right now, appears in the world –and because we have not developed herd immunity to\xa0it, it tends to spread very quickly and it takes a while\xa0for that herd immunity to catch up. In order to evaluatespecifically how a virus is spreading through the\xa0world and affecting populations one needs to look at\xa0how quickly or how widespread it already is and also\xa0how lethal and fatal it has been. The fact is these two\xa0factors don t always go together rather they re\xa0independent to one another, coronavirus so far is\xa0making a big impact because of how widespread it is\xa0due to how easily and how quickly it can spread\xa0through our community.\xa0As for how lethal it is and how that affects our health\xa0care system; the most common symptoms are fever\xa0dry cough and tiredness and critical symptoms\xa0include difficulty acute respiratory distress syndrome\xa0(ARDS) chest pain or pressure and loss of speech or\xa0movement. It is to be noted that the timeline of virus\xa0spread matters so the WHO has declared COVID-19 a\xa0pandemic. This is a public health concept that means a\xa0virus or an illness actually that is spreading as\xa0separate areas of the world concurrently. It should\xa0also be kept in mind that this term “Pandemic” only\xa0describes how prevalent and widespread it is, it does\xa0not describe how lethal it is.\xa0So why is the current virus causing COVID-19 is so\xa0good at spreading. As mentioned earlier that since\xa0there is no herd immunity and as it spreads, none of us\xa0have encountered it before our bodies are not\xa0prepared and cannot fight off the virus very quickly.\xa0Furthermore, because it s actually not that lethal since\xa080% of people who suffer from it have either very\xa0mild symptoms or no symptoms and even those who\xa0go on to develop symptoms can have a very long\xa0latent period of up to 10 days where they are\xa0contagious. The problem that it is so widespread\xa0because 80% of people have no symptoms or are very\xa0mild symptoms and can recover easily on their own.\xa015 percent would probably need hospital care and 5\xa0percent likely needs Intensive Care Unit level critical\xa0treatment. Further the most vulnerable population arethe elderly or people who are already sick but the fact\xa0that it spreads quickly means that the 5% that needs\xa0intensive care will need it very quickly and in a\xa0concentrated period of time.\xa0This is very different from something like Ebola virus\xa0where by the time one will have it and he/she is\xa0contagious plus the symptoms were very dramatic and\xa0it could be easily determined who has it. In case of\xa0COVID-19, most people spend a long time able to\xa0pass a virus without either knowing it or with very\xa0mild symptoms. Having mentioned that it s almost\xa0impossible to completely shut down the spreading of\xa0this virus without dramatic measures to contain\xa0people in such a highly mobile and globally accessible\xa0world. Because we don t know who is sick especially\xa0in the earlier parts of the epidemic and that s why\xa0we re seeing countries one by one taking really\xa0dramatic shutdowns. It is worth mentioning that flu\xa0that also puts a percentage of people in critical\xa0conditions and leads to death in especially in the\xa0vulnerable populations but if we look at flu season\xa0around the world it is a six-month period of time.\xa0Putting that into perspective the hospitals and\xa0personnel; considered limited resources, and the\xa0respiratory machines that are needed to support\xa0people and the doctors to see them - might be able to\xa0support people periodically needing it over a sixmonth\xa0period of time. But the case of COVID19 is\xa0different, given the fast concentrated spike of critical\xa0patients, the systems can get overwhelmed like seen in\xa0Italy and China. So the 5% that need critical care\xa0might not have the doctor, the ventilator and the\xa0infrastructure to help them through the worst of the\xa0illness.\xa0That s is the reason of spread and lethality of COVID-19\xa0- the delayed response and conjoined with\xa0difficulty in containing a virus that spreads quickly\xa0through healthy people has been the crux of the\xa0problem.