dotlah! dotlah!
  • Cities
  • Technology
  • Business
  • Politics
  • Society
  • Science
  • About
Social Links
  • zedreviews.com
  • citi.io
  • aster.cloud
  • liwaiwai.com
  • guzz.co.uk
  • atinatin.com
0 Likes
0 Followers
0 Subscribers
dotlah!
  • Cities
  • Technology
  • Business
  • Politics
  • Society
  • Science
  • About
  • Environment
  • People

What Are Viruses Anyway, And Why Do They Make Us So Sick? 5 Questions Answered

  • February 28, 2020
Total
0
Shares
0
0
0

You may sometimes have felt like you “have come down with a virus,” meaning that you became sick from being exposed to something that could have been a virus. In fact, you have a virus – actually, many – all the time. Some viruses cause the common cold, and some are crucial to human survival. New viruses can also emerge, and they typically create illness in humans when they have very recently jumped from another species to humans. As world health leaders try to determine how to respond to the new coronavirus, virus expert Marilyn J. Roossinck answers a few questions.

Patients infected with COVID-19 rest at a temporary hospital in Wuhan, China, Feb. 17, 2020. Getty Images/Xiao Yijiu

1. What is a virus?

Defining a virus has been a challenge because every time we come up with a good definition someone discovers a virus that breaks the rules. Viruses are entities that infect cellular life. They are very diverse. The simplest just have a couple of genes made of RNA or DNA wrapped up in a protein coat. Others have hundreds of genes, more than some bacteria.

All viruses are ultimately parasites. They require a host for replication. They cannot generate their own energy like cells can.

2. Why does a virus make people sick?

When a new human virus disease appears, it is most often because the virus has jumped from a different species into humans. The worst viruses are often the ones that have very recently jumped into the species.

After jumping species, the virus goes through a process of adjustment to its new host. The real challenge, however, is to the host. As it tries to figure out how to adjust to an invasion from something completely new, the immune system overreacts. This is what makes the host sick. It usually isn’t an advantage for the virus to make people sick; it is an accident of the hosts’ immune system overreacting to something it doesn’t recognize.

Viruses that have been in a host for a long time are less likely to cause disease. For example, HIV jumped into humans from wild primates, in whose bodies it wasn’t causing any disease.

Every virus-host relationship is different. In most cases, viruses do not cause any disease, and many are beneficial. For example, in mice a herpes virus prevents infection from the plague bacteria.

3. Why is it so important to know the original source?

If the virus comes from an animal, knowing what that animal is can help break the chain of infection. Knowing the source also helps scientists understand mutations that might have occurred in the virus’ genome. That’s because host-jumping affects the variation in a virus genome. When a virus has been in its host for a long time, the genome is fine-tuned to that host, and mutations are not tolerated.

Students in Bangladesh are shown wearing masks Jan. 29, 2020, in an effort to stop the spread of the new coronavirus. Experts are divided on whether wearing masks makes a difference, but most agree that hand-washing is imperative. Getty Images/Mehedi Hasan/NurPhoto

4. SARS was a formidable foe, and then seemed to disappear. Why?

Measures to contain SARS started early, and they were very successful. The key is to stop the chain of transmission by isolating infected individuals. SARS had a short incubation period; people generally showed symptoms in two to seven days. There were no documented cases of anyone being a source of SARS without showing symptoms.

Stopping the chain of transmission is much more difficult when the incubation time is much longer, or when some people don’t get symptoms at all. This may be the case with the virus causing CoVID-19, so stopping it may take more time.

5. What is the best way to treat viruses?

Viruses don’t respond to antibiotics, and in some cases taking antibiotics can make things worse, because the normal bacteria in the gut are an important part of the immune response. Antiviral drugs can work with some viruses, but the mutation rate of most viruses means that they become resistant to antivirals very quickly.

The best treatment is to give the patient the best tools to allow their own body to fight off the infection. This usually means rest and keeping hydrated. Virus infection can suppress the immune system, so patients should be monitored for secondary infections that might require other treatments. Prevention is important. Sick people need to be isolated, and healthy people need to take precautions.

Most respiratory viruses are not transmitted just by breathing them in from sick people, but by getting them on your hands from tiny droplets that sick people distribute by coughing or sneezing, and then touching your face. Good hand-washing is important!

The Conversation

Marilyn J. Roossinck, Professor of Plant Pathology and Environmental Microbiology, Pennsylvania State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Total
0
Shares
Share
Tweet
Share
Share
Related Topics
  • Antiviral Drugs
  • Coronavirus
  • COVID-19
  • SARS
  • Virus
dotlah.com

Previous Article
  • Society

What Are Viruses Anyway, And Why Do They Make Us So Sick? 5 Questions Answered

  • February 28, 2020
View Post
Next Article
  • Technology

ST Engineering And Janus Technologies Launch Asia’s First Cloud, Firmware Endpoint Security Solution

  • February 28, 2020
View Post
You May Also Like
View Post
  • People
  • Politics

Singapore PM Wong arrives in Malacañang

  • dotlah.com
  • June 4, 2025
View Post
  • Featured
  • Features
  • People

Conclave: How A New Pope Is Chosen

  • Dean Marc
  • April 25, 2025
View Post
  • People

PM Wong takes Scoot flight, fellow passengers cheer

  • dotlah.com
  • October 16, 2024
singapore-carbon-market-alliance
View Post
  • Economy
  • Environment

Launch of Singapore Carbon Market Alliance (SCMA) to enable access to and supply of high-quality carbon credits

  • dotlah.com
  • August 1, 2024
dotlah-pm-lee-lawrence-wong-9656d4cd-1fa4-40ed-905d-e19e639b8476_728802dd
View Post
  • Lah!
  • People
  • Politics

End of Lee Era for Singapore as PM Steps Down

  • dotlah.com
  • May 16, 2024
View Post
  • People
  • Politics

‘A much bigger step forward’: Lawrence Wong on his journey to becoming Singapore’s fourth PM

  • dotlah.com
  • May 15, 2024
DPM Lawrence Wong will be Singapore's fourth prime minister on May 15. ST PHOTO: LIM YAOHUI
View Post
  • Lah!
  • People
  • Politics

7 things to know about Singapore’s next prime minister Lawrence Wong

  • dotlah.com
  • May 15, 2024
When asked about his leadership style, DPM Lawrence Wong said he will be open and consultative, but he will not shirk from doing what is necessary for Singapore's future. ST PHOTO: LIM YAOHUI
View Post
  • Features
  • Lah!
  • People
  • Politics

‘We are prepared to relook everything’: Lawrence Wong on a changing society and his hopes for S’pore

  • dotlah.com
  • May 15, 2024


Trending
  • 1
    • Lah!
    • Technology
    Sustainable Urban Farming – Lighting Up Our Local Farms
    • March 12, 2021
  • 2
    • Cities
    • Environment
    • People
    The 4 Plausible Futures Of The World: Post Anthropocene
    • March 18, 2020
  • 3
    • Lah!
    Towards Smart And Clean Energy-Powered Service Stations
    • March 7, 2021
  • 4
    • Cities
    • Technology
    ABB And Keppel Sign Memorandum For Digital Collaboration
    • March 7, 2022
  • 5
    • Technology
    NTU Singapore Leverages AI And Machine Learning To Fight Money Laundering
    • August 22, 2019
  • 6
    • Lah!
    Singapore Ranks As The World’s Most Competitive Economy
    • October 25, 2019
  • public-bus-mitchell-johnson-nd5oU1Duhf0-unsplash 7
    • Cities
    Want To Create 5 Million Green Jobs? Invest In Public Transport In Cities
    • April 15, 2021
  • 8
    • Technology
    Singapore Among Top Five Countries For Best Online Safety For Children In New DQ Institute -Singtel Study
    • February 13, 2020
  • 9
    • Technology
    Huawei Cloud & AI Innovations Lab Launch In Singapore
    • April 26, 2019
  • 10
    • Lah!
    Creating A Community, Changing Mindsets And Cleaning Up The Seas
    • June 22, 2021
  • oped-london-is-a-great-city-be-warned-202305 11
    • Cities
    • dotZero
    • Op-Ed
    • Outsights
    London & UK Is The Best! You Have Been Warned. Part 1-ish.
    • May 21, 2023
  • 12
    • Lah!
    Satisfaction In Singapore’s Consumer Services Improves Across Most Industries
    • March 26, 2020
Trending
  • 1
    PBBM asks Singapore to invest more in PH renewable energy projects
    • June 6, 2025
  • 2
    Singapore PM Wong arrives in Malacañang
    • June 4, 2025
  • 3
    Renewable energy, carbon credits are priority areas of cooperation for Singapore, Philippines: Lawrence Wong
    • June 4, 2025
  • 4
    Singapore businesses eye more investments in PH, says PM Wong
    • June 4, 2025
  • 5
    The Summer Adventures : Hiking and Nature Walks Essentials
    • June 3, 2025
  • 6
    Trump’s global trade plans are in disarray, after a US court ruling on ‘Liberation Day’ tariffs
    • May 29, 2025
  • 7
    315,000 Singaporeans have used new career and skills planning tool by SkillsFuture Singapore
    • May 23, 2025
  • college-of-cardinals-2025 8
    The Definitive Who’s Who of the 2025 Papal Conclave
    • May 8, 2025
  • conclave-poster-black-smoke 9
    The World Is Revalidating Itself
    • May 7, 2025
  • oracle-ibm 10
    IBM and Oracle Expand Partnership to Advance Agentic AI and Hybrid Cloud
    • May 6, 2025
Social Links
dotlah! dotlah!
  • Cities
  • Technology
  • Business
  • Politics
  • Society
  • Science
  • About
Connecting Dots Across Asia's Tech and Urban Landscape

Input your search keywords and press Enter.