Covid-19 Pandemic: Part 2: Signs and Symptoms, Duration and Outcome of the Disease

Published in November 2021

This paper continues from paper 1 and discusses how Covid-19 affects human beings, how serious it is, how it is transmitted and how long it lasts and how lethal the disease can be. We have also tried to discuss variation of the disease rates among the countries and within the country among different races. How deaths were higher initially and how it changed with more knowledge.

We discussed last month the historical context of Covid-19 pandemic versus earlier pandemics that the world had faced. In this month’s edition we discuss how the disease affects human being, how serious it is, how it is transmitted, how long does it last and how lethal the disease can be. 

Signs and Symptoms of Covid-19

People with COVID-19 have had a wide range of symptoms reported – ranging from mild symptoms to severe illness. Symptoms may appear 2-14 days after coming in contact with a patient who is having Covid-19 and is infectious. Depending upon how long they were in contact with the sick person and whether the sick person was shedding too many viruses or small quantity, person may develop mild to severe symptoms. Early phase of the disease, they are most infectious.   

People with these symptoms may have COVID-19: Fever or chills, Cough, Shortness of breath or difficulty in breathing, Fatigue, Muscle or body aches, Headache, New loss of taste or smell, Sore throat, Congestion or runny nose, Nausea or vomiting, Diarrhea. As the list indicates, many of these symptoms can occur in various other conditions like flu or common cold and so diagnosis can be missed unless we are conscious and go for the laboratory diagnosis. Loss of smell and taste are fairly specific symptoms for Covid-19. Shortness of breath indicates more severe form of the disease. Covid 19 cases sometimes may have no symptoms and even then, they may be infectious and they are called asymptomatic or pre-symptomatic cases. For transmission they can be more dangerous since they will be moving freely in the society. Young children and school going children fall in this category who usually have mild symptoms or no symptoms but they can bring infection to the family members easily. We, however do not know the exact details of transmission occurring by asymptomatic patients but it is confirmed that they do transmit and spread the disease.  Pulse oximeter showing oxygen saturation below 95% is another important sign for monitoring the progress of the disease. Oxygen saturation going down is an indication to get admitted to the hospital. 

How does Covid-19 Virus Spread from Person to Person?

We all continuously breath out small particles. These are called droplets. These droplets are more when we talk or cough and goes to a larger distance than when we just breathe. COVID-19 spreads when an infected person breathes out very small particles that contain the virus (these are called droplets). These particles can be breathed in by other people or land on their eyes, noses, or mouth. In some circumstances, they may contaminate surfaces they touch. People who are closer than 6 feet from the infected person are most likely to get infected. But others can get infected too. 

COVID-19 is spread in three main ways:

• Breathing in air when close to an infected person who is exhaling small droplets and particles that contain the virus.
• Having these small droplets and particles that contain virus land on the eyes, nose, or mouth, especially through splashes and sprays like a cough or sneeze.
• Touching eyes, nose, or mouth with hands that have the virus on them.

Initially we had been stressing the importance of transmission through touch and through breathing almost equal. Now, over a time, we have accepted that it is largely a transmission through breathing mainly and touch does play a part but not as much as breathing small droplets. 

Clinical Course and Recovery and Death Rates of the Disease and Outcome of the Disease

Study suggests that while most people recover from COVID-19 within two weeks, one in ten people may still have symptoms after three weeks, and some may suffer for months. During the disease course, person may feel weak and develop symptoms discussed above. Highest number of deaths occurred in USA that is 741055 from 44.45 million total cases giving us the death rate at 1.6% of the cases dying (See the graphs), the second highest number of deaths are in India with 34 million cases and 45100 deaths at the rate 1.3% of cases dying while highest death rate (not number) was observed in Peru at 9.1% of the cases dying. Thus overall, over 98% of them survive the disease and recover gradually. The admission to hospital and death rates are many folds more among senior age over 65 years as compared to younger generation in the age group of 20-29 years though total number of infections is higher in younger age group.

Death rate was observed higher in the early part of pandemic when we had no past experience, did not know enough of how to treat the disease and when the vaccine did not exist. As the time passed, treatment improved, vaccine discovered bringing down the seriousness of the disease and reduced the death rate.

Covid-19 Disease: Is it Higher in Asians?

A scientific paper from very reputed British Journal, Lancet published in April 2021 showed from 50 studies including over 18.7 million patients that both Black and Asians ethnicities had a higher risk of Covid-19 infection compared to White individuals. Their admission in the hospital and deaths were also higher compared to white population. 

Coming Up 

In the coming months ahead, we will discuss how to protect ourselves and prevent the spread of the disease, various diagnostic tests, social and economic impacts in the societies, various vaccines and their doses, how best to get ourselves protected including vaccinations and lessons learnt for the future one by one.