Understanding COVID-19

March 12, 2020

Over the past month, there has been a growing body of research and clinical information on the virus involved in the global epidemic.

The complete clinical picture with regard to COVID-19 is not yet fully known. Over the coming months, we will learn more about the biology of SARS-CoV-2.

This document aims to summarize the most important points about the Covid-19 virus that we are currently aware of.

Part 1: What are the names of the virus and the disease?

The virus is named SARS-CoV-2 / 2019-nCoV.
The disease that the virus causes is called COVID-19.

Part 2: What are coronaviruses? How is 2019-nCoV related?

Coronaviruses are a family of RNA viruses that are common in people and animals.
Coronavirus is named due to their appearance: when viewed under an electron microscope, they look like halos (coronas).
Coronaviruses are known to cause upper respiratory infections. Until this virus, it was not known to cause pneumonia.
Seven human coronaviruses (HCoVs) have now been identified:
1. HCoV-229E,
2. HCoV-OC43,
3. HCoV-NL63,
4. HCoV-HKU1,
5. SARS-CoV
  (Severe acute respiratory syndrome),
6. MERS-CoV
  (Middle East respiratory syndrome),
7. SARS-CoV-2
  (2019-nCoV; the most recent virus).

Of these seven coronaviruses, three of them (SARS, MERS, 2019-nCoV) were due to animal-to-human transmission, and are known to have more serious consequences for those they infect.

Part 3: What are the symptoms of COVID-19?

Diagnosis of COVID-19 is complicated, due to the diversity in symptoms and results being dependent on the severity of disease.
Based on best available research, the most common symptoms that appear 2-14 days after exposure, are
- Fever
- Cough
- Shortness of Breath
Emergency warning signs for severe COVID-19 are
- Difficulty breathing or shortness of breath
- Persistent pain or pressure in the chest
- New confusion or inability to arouse
- Bluish lips or face

Part 4: Who gets sick from COVID-19 and what happens to them? How dangerous is COVID-19?

Most information being circulated is based on a study from China (Guan et. al., 2020), below are the clinical characteristics of COVID-19 they found:
1. Median age = 47 years.
2. 42% of patients were female.
3. 6% of cases would be admitted to ICU, require invasive mechanical ventilation, or have illness resulting in death.
  Of this group, most are over 65-years-old; none are below 20.
4. The most common symptoms are fever, cough and shortness of breath. Diarrhea is uncommon but present in a small number.
5. Patients who were admitted to hospital showed abnormally low levels of lymphocytes in the blood (lymphocytopenia).
6. Chest computed tomography (CT) found “ground-glass opacity” in 56.4% of cases.
Current best evidence suggests:
- Most cases are adults, aged > 35 years.
- COVID-19 infections appear to be less common in children. Children tend to be less severe cases and have good outcomes (to them it’s more like the common cold).
- More men than women are infected with COVID-19.
- Not all cases of COVID-19 will have affected lungs. Slightly more than half of cases will have normal chest X-rays.
- COVID-19 is associated with low levels of lymphocytes in the blood.
- Most cases are mild-to-moderate, and are able to recover with support and rest.
- A small percentage of cases will become severe, two groups are especially vulnerable:
- older people
- those with severe underlying health conditions.
- Covid-19 is much less deadly than SARS or MERS.
  Case-fatality rate measures the number of deaths among those infected and this is now coming out consistently to be much lower for Covid-19.
- On the other hand, this disease is far more capable of transmitting between humans than SARS or MERS.
  Transmissibility is measured by its reproduction number – cases directly generated from each case – and this is showing to be more like pandemic influenza.

Part 5: How does it spread? How to assess risk of getting COVID-19?

The virus is spread primarily by respiratory droplets, similar to other viruses. These droplets are most present in coughs and sneezes.
At present, it is unclear exactly how contagious the virus is between people, though we do know it is more contagious than SARS and MERS.
For the majority of people, the immediate risk of being exposed to the virus that causes COVID-19 is thought to be low.
People who have been in close contact with people with COVID-19, are at higher risk.
Close contact is defined as
- Anyone who provided care for someone with a confirmed case,
- Anyone who stayed in the same place as a confirmed case (e.g. household members)
- Anyone who had close (i.e. less than 2m) AND prolonged contact (>30 minutes) with a confirmed case (e.g. shared a meal)

Part 7: What are the tests for COVID-19? What happens during testing?

Testing is done to find pieces of the virus’ RNA (most commonly through a PCR test).
This can be done through three specimens:
- Fluids from the lower and upper respiratory tract through nose and mouth.
- Serum through a blood sample.
- Sometimes, stool and urine samples are collected.
If you are advised to go for screening, you can obtain screening at the National Centre for Infectious Diseases (NCID).
At the entrance, you will be interviewed by medical personnel, who will ask the following
- name,
- phone number,
- address,
- occupation,
- IC number
- Contact with suspected or confirmed cases or outbreak locations.
The NCID team will determine the risk level of you being exposed to the virus, and direct you to a hall with tables and chairs.
You will be asked to complete a questionnaire, which will include
- Your travel history
- Whether you have had close contact with confirmed or suspected cases of COVID-19
- Whether you had previously visited locations of with known outbreak clusters.
Your vitals will be recorded, including temperature, symptoms, SPO2 and blood pressure.
A chest X-ray and nasal swab will be conducted.
A doctor will speak with you and advise you on additional tests and further action.
You may be warded or sent home on hospitalization leave for 5 days.
Test results are expected within one-two days. If you are negative, they may take longer to contact you due to backlog.

Part 8: How do we treat it? How do we prevent it?

At this time, there is no vaccine to protect against COVID-19 and no medications approved to treat it.
Non-pharmaceutical interventions would be the most important response strategy.
Everyday preventive action help to prevent the spread of respiratory diseases, including:
- Avoid close contact with people who are sick. (See part 5 for definition for close contact)
- Avoid touching your eyes, nose, and mouth.
- Stay home when you are sick.
- Cover your cough or sneeze with a tissue, then throw the tissue in the trash.
- Clean and disinfect frequently touched objects and surfaces using a regular household cleaning spray or wipe.
- Facemasks should be used by people who show symptoms of COVID-19 to help prevent the spread of the disease to others.
  The use of facemasks is also crucial for health workers and people who are taking care of someone in close settings (at home or in a health care facility).
- Observe proper hand-hygiene; Wash your hands often with soap and water for at least 20 second.
Have a plan if you get sick:
- Consult with your healthcare provider
- Know how to get transport
- Stay in touch with others through phone or email
- Know who can provide you with care.

Part 9: Can we be confident that COVID-19 will be managed well?

The following are comments from NCID Senior Consultant & Assoc. Prof. Ooi Peng Lim, and Dr Leo Yee Sin, Executive director of NCID

Insecurity amidst uncertainty is to be expected. Many reports, some untrue, are making their rounds in chat groups, stoking public anxiety, doubt and fear.
Whether the outbreak lasts weeks or months, halting this outbreak in its tracks ultimately depends not so much on disease duration as on our collective resilience.
Sustainability is key to preparing for a long battle. Support for each other is crucial to our psychological defence.
Singapore’s unique size works in our favour. Many challenges are much more manageable in scale here than they would be in other countries.
We have ample resources, invested heavily during peacetime. We also have the will to learn from our mistakes and stand together.
Just as with SARS, here is a chance for us to improve our community-based response with social norms of self-reliance, solidarity, and cooperation.
With concerns over rapid local spread, we must wash our hands regularly and if we feel unwell, wear a mask and avoid contact with others. We must also be judicious in the use of limited resources.
Various groups and organizations, both within and outside of HCA, are working together to address the situation and improve our understanding of the disease.

Part 10: Protecting against stigma and misinformation

COVID-19 is unique in that it is occurring during a time of easy access to instant news and social media.
This has led to the spread of misinformation and stigma against those suspected to have COVID-19, those who are confirmed to have COVID-19, and healthcare workers.
Bad news spreads faster than good news. Media sites prioritise similarities, which compound biases in line with previous viewpoints and worsen fear.
Take the following steps to counter stigma and reduce misinformation:
- Maintain privacy and confidentiality of those seeking healthcare and those who may be part of any contact investigation.
- Quickly communicate the risk or lack of risk from associations with products, people, and places.
- Raise awareness about COVID-19 without increasing fear.
- Share accurate information about how the virus spreads.
- Speak out against negative behaviors, including negative statements on social media about groups of people, or exclusion of people who pose no risk from regular activities.
- Be cautious about the images and news that are being shared. They may not be accurate or are enforcing negative stereotypes.

References

American Society for Microbiology (31 Jan 2020). 2019 Novel Coronavirus (2019-nCoV) Update: Uncoating the Virus. American Society for Microbiology website. Accessed here: https://asm.org/Articles/2020/January/2019-Novel-Coronavirus-2019-nCoV-Update-Uncoating

Guan, W. J., Ni, Z. Y., Hu, Y., Liang, W. H., Ou, C. Q., He, J. X., … & Du, B. (2020). Clinical characteristics of coronavirus disease 2019 in China. New England Journal of Medicine. Accessed here: https://www.nejm.org/doi/full/10.1056/NEJMoa2002032