Why is it so difficult to contain COVID-19 pandemic?

Why is it so difficult to contain COVID-19 pandemic?

Last Reviewed : 12/16/2020
Why is it so difficult to contain COVID-19 pandemic?

When Novel Coronavirus became an endemic in China, no one imagined that it would turn into a pandemic spreading all across the globe. Even when there were first few cases in Washington state in the US, epidemiologists considered Novel Coronavirus as a zoonotic virus that spreads from animals to human beings. It was also thought to spread from travel to China and other affected countries and never believed that it would spread in the community. Within a few weeks, however, gravity of the situation changed. It rapidly started spreading in the communities. COVID-19 was soon declared as a public health emergency in most of the countries throughout the world.

While every country has been toiling to contain this pandemic, it became obvious that COVID-19 pandemic is very difficult to contain. There are multiple reasons why it is extremely difficult to contain this pandemic:

  1. Spreading the virus before developing symptoms: When people are exposed to Coronavirus, it usually takes anywhere from 2 to 14 days before symptoms develop. The median time to develop symptoms is around 5 days. Most of the affected persons start spreading the virus after symptoms appear. However, some affected individuals start spreading the virus even before symptoms develop. This is called as asymptomatic carrier state. It is also possible that few affected individuals may not even develop any symptoms at all. They may remain asymptomatic throughout the course of the illness. Earlier in the course of this pandemic, it was thought that the role of asymptomatic spread was minimal. However, as it became more rampant, it became obvious that asymptomatic spread is playing a major role.
  2. Touching fomites: Fomites are the objects or materials that likely spread the infection. Cell phones, utensils, clothes, furniture, bathroom doorknobs, taps are some common fomites known to spread the disease from one person to another. Coronavirus may last from few hours up to 9 days depending on the type of the surface. When infected people cough or sneeze, Coronavirus present in the droplets may settle down on the fomites. When a healthy individual touches the fomites and also touches his or her nose, eyes or mouth, it spreads rapidly to the healthy individual. On average, we touch our face around 300 times a day. It is extremely difficult to avoid the urge to touch the face as it happens subconsciously. It is very important to wash hands thoroughly and avoid touching the face.
  3. Airborne spread: Based on the study published in the New England Journal of Medicine, Coronavirus can remain viable in aerosols (small particles floating in the air) for about three hours. When an infected person coughs or sneezes few aerosols are produced depending on the intensity of cough and the amount of respiratory secretions. This increases the risk of airborne spread of the infection.
  4. Traveling: In the United States, even during the ‘stay at home’ order, there are no restrictions on travel. Now, imagine, if an infected person in an asymptomatic carrier state travels from one place to the other by air, he or she may infect hundreds of people on the way to their destination. Similarly, any other public or private transportation may result in the continual spread of the infection. Without ‘complete’ lockdown, it may not be easy to contain this pandemic.
  5. Scarcity of test kits: Even though the pandemic started spreading among the communities, because of the scarcity of test kits, not every person with fever, cough and other flu-like symptoms are tested unless they have close contact with confirmed COVID-19 individual or history of travel to the affected places. It may not be even possible to test everyone when there are thousands of cases in the community. Unfortunately, with this approach, people acquiring the infection at public places, grocery stores, pharmacies or during travel are not being tested. These infected untested individuals may spread the infection to others in the community.
  6. Lax self-quarantine: People who are never tested for COVID-19 who have mild fever and cough may not follow strict quarantine guidelines. If testing is done and COVID-19 is confirmed, compliance to self-quarantine is expected to be significantly higher. No one really wants to spread the infection intentionally if they know they have the infection.
  7. Milder symptoms: About 81% of the affected individuals have mild symptoms or no symptoms at all. When people have mild or no symptoms, they may not be aware that they are infected with Novel Coronavirus. And they may not follow strict self-quarantine guidelines to prevent infection to others in the community.
  8. Congested neighborhoods: Social distancing may not be easy when neighborhoods are closed and congested. Coronavirus infection may spread easily in such neighborhoods.
  9. Migration: People from one ‘hotspot’ tend to move to a place where the infection rate is low. For example, New York is the worst-hit state in the United States. As few people are moving out of New York to other states, there is a possibility that they might carry infection with them to the new places.






  1. J Microbiol Immunol Infect. 2020 Mar 4. pii: S1684-1182(20)30040-2. doi: 10.1016/j.jmii.2020.02.012. Asymptomatic carrier state, acute respiratory disease, and pneumonia due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2): Facts and myths. Lai CC, Liu YH, Wang CY, Wang YH, Hsueh SC, Yen MY, Ko WC, Hsueh PR.
  2. Rothe C, et al. Transmission of 2019-nCoV infection from an asymptomatic contact in Germany. N Engl J Med. 2020:2019–20.
  3. Zhonghua Yan Ke Za Zhi , 56 (0), E008 2020 Mar 14, Consideration and Prevention for the Aerosol Transmission of 2019 Novel Coronavirus. Y X Yu , L Sun, K Yao, X T Lou, X Liang, B W Zhao, Q X Mu, H Du, Y Zhao, H Zhang
  4. Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1. Van Doremalen et al. N Engl J Med. https://doi.org/10.1056/NEJMc2004973
  5. Biosci Trends. 2020 Mar 19. doi: 10.5582/bst.2020.01482. Analysis of COVID-19 infection spread in Japan based on stochastic transition model. Karako K et al.

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