Author: James Ong

My name is James Ong. I am The Active Evaluator. I work on program evaluation, but I also branch off to areas that interest me.

The differences between COVID-19 and seasonal influenza: a virus perspective

Electron microscopic images of coronaviruses (left) and influenza viruses (right).

The COVID-19 pandemic, driven by a novel coronavirus (SARS-CoV-2), has spread rapidly around the world. Some people (and even global leaders in the USA and Brazil) mistakenly believe that COVID-19 infection is just seasonal influenza as they produce similar symptoms. You might have even tried to convince some of your relatives that COVID-19 infection is different to that of seasonal flu. You also know that COVID-19 is more contagious and deadlier than seasonal influenza.

In this blog post, I will be taking a different tack on the issue. I will be comparing the viruses themselves to show you how COVID-19 is similar and different to seasonal influenza. This blog post will describe what these viruses are, where they come from and how they infect and cause disease. I hope that this blog post will give you a new way to persuade other people that COVID-19 is different from seasonal influenza.

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The Science behind “Cells at Work!” Special 1: “Heat Stress (and Fluid Balance)”

Sweat gland depleted of sweat

Consider this scenario:

You are competing in the Comrades Marathon, the largest and oldest ultramarathon in the world that is held in South Africa. It involves running 90km from Pietermaritzburg to Durban, running up and down five hills along the way. You start running at 5:30AM and you have 12 hours to finish the course.

Even though the weather is cool with a top of 16°C (60.8°F), you still feel sweaty as you run the course. What would you need to consider when you are running in the Comrades Marathon?

Strenuous activity such as running produces sweat that cools the body down. However, when sweating stops functioning, the person suffers from heat stress where the body continues to heat up. This leads to symptoms such as dizziness, obscured vision and fainting as the body struggles to function normally. Over two separate episodes, heat stress was resolved in two different ways. In episode 11, the cells are saved by an injection of intravenous fluid into the body. However, in a special episode aired exclusively in Japan, the cells are saved by Pocari Sweat, a Japanese sports drink.

How does taking in such fluids treat heat stress? In this blog post, we will look at how the body normally scavenges fluids and salts from urine to keep sweating and how taking in fluids helps or hinders this process.

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The Science behind “Cells at Work!” Episode 11: “Heat Stress”

In this episode, we look at how the body responds to a hot day!

Consider the following scenario:

A 19-year-old man works as a traffic controller, holding a stop/slow sign to direct traffic while his team repairs a road lane. The weather is hot and humid with a temperature high of 38°C. In the morning, he feels hot and sweaty but is well enough to direct traffic. However, later in the day he has a headache and feels disoriented. His fellow workers berate him for letting traffic through which disrupts their work. A few minutes later, he collapses. Everyone stops what they were doing and comes to see if he is OK. What happened and what should everyone do next? 

The human body works at a strict temperature range of around 37°C (98.6°F) to ensure that the body can function properly. When the body gets too hot or cold, the body activates various mechanisms to return body temperature to normal. In the anime episode, when these mechanisms fail, the body temperature can continue to increase, making it a struggle for the cells and human body to function properly. How does your body keep itself cool while working under hot, humid conditions? This blog post will explain how the body regulates its temperature and what happens when such mechanisms break down.

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How does the immune system respond to COVID-19 infection? Explaining the article “Breadth of concomitant immune responses prior to patient recovery: a case report of non-severe COVID-19”

The COVID-19 pandemic, caused by the novel SARS-CoV-2 coronavirus, has massive global ramifications. As of 1st April 2020, the pandemic has produced 858,785 cases with 42,151 deaths. The pandemic has stretched hospitals and public health systems in developed countries such as Italy and the United States and also affected local and global economies with travel restrictions, falling stock prices and rising unemployment. Researchers around the world are studying the SARS-CoV-2 virus and COVID-19 infection to develop treatments and vaccines that can stop the pandemic. In particular, researchers are looking into how the immune system responds to COVID-19 infection.

Recently, researchers at the Peter Doherty Institute for Infection and Immunity in Melbourne, Australia published an article which described, for the first time, how the immune system responds to COVID-19 infection. In this study, researchers tracked the immune response of a patient who was hospitalised with COVID-19 infection but later recovered. They found that the patient was able to mount an effective immune response to the SARS-CoV-2 virus that persisted even after the virus was eliminated.

I like this article because it describes very simply how the immune system responds to COVID-19 infection. In addition, the article is quite short and contains results that, with further explanation, anyone can interpret and understand. In this blog post, I will explain how the immune system works and how this relates to what researchers found in their study. I hope this blog post will ignite your interest in the immune system and how it responds to COVID-19 infection. Who knows, you might even start reading and understanding some academic articles on COVID-19 infection!

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The Science behind “Cells at Work!” Episode 10: “Staphylococcus aureus”

In this blog post, we learn more about a common bacterial infection that can cause massive problems in the human body: Staphylococcus aureus!

In this episode, Red Blood Cell witnesses Monocyte doing a lot of weird things around the body such as sleeping in a hot spring and hiding behind lamp poles. Suddenly, Staphylococcus aureus (S. aureus) invades the human body to take revenge of her cousin who was killed in episode 2. Neutrophils appear in time to kill them, but the remaining bacteria fuse to form one giant monster that attacks the neutrophils. Just as the neutrophils get overwhelmed, the monocytes arrive and transform into macrophages. The macrophages beat up the S. aureus giant, breaking it off into individual bacteria that run away and get killed. Following this, macrophages and neutrophils thank each other for working together to eliminate S. aureus.

What happens during S. aureus infection and do macrophages really save neutrophils from being overwhelmed? Find out as we dive into S. aureus infection.

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