Viral Evolution - A Timely Reminder in Support of a Back to Basics Approach
By: Megan Sharpe
Viruses are microorganisms that exist almost everywhere. They can infect most living things including humans, animals, plants, fungi and even bacteria. Some viral infections occur with little or no impact to the host but others have the potential to be fatal.
Viruses have a very simple single-cell structure with a protein coat and a single type of nucleic acid. However, they lack a metabolism and the ability to reproduce without a host cell. Therefore they need currently living organisms to live. Only when it is associated with a living cell does a virus become able to replicate.
Viruses can survive for various periods outside of the host cell but are unable to reproduce until they find a new host. Because viruses are reliant on other living cells to reproduce this means they are unlikely to survive for long periods of time on inanimate objects.
Examples of common viruses include: Influenza (the flu), Herpes Simplex (cold sores), Varicella (chickenpox), Rubeola (measles), Rubella (German Measles), Human Immunodeficiency Virus (HIV), Poliomyelitis (polio).
Human coronaviruses were first identified in the 1960s and were named for their crown-like spikes on the surface. Coronaviruses are split into 4 subgroups - alpha, beta, gamma and delta. There are currently, including the most recent strain of human coronavirus, seven strains of human coronavirus.
Common human coronaviruses
Other human coronaviruses
Potentially coronaviruses that infect animals can evolve and become harmful to the human population as they become a novel (new) coronavirus.
Three recent examples of evolution from animal to human are 2019-nCoV, SARS-CoV, and MERS-CoV.
The World Health Organisation (WHO) reported on 9th January 2020 that a novel coronavirus had been identified by Chinese authorities. The virus is associated with an outbreak of pneumonia in Wuhan City, Hubei Province, China.
At this point, the 2019-nCoV is still considered an outbreak meaning a sudden and unexpected increase in disease in a particular place and time period. Although the WHO has declared 2019-nCoV as a global health emergency, it is yet to be reclassified as a pandemic but is expected to be so. A pandemic is an epidemic or outbreak that has become widespread across a country, continent or the world.
Like any viral infection, those most at risk may already have a potentially weakened immune system. This includes babies and young children whose immune systems are yet to develop along with the elderly whose immune systems may have begun to decline. People with existing illnesses and conditions and also those with extreme lifestyle factors (stress, diet, drug use etc) may also be more readily infected.
Image: https://en.wikipedia.org/wiki/Coronavirus
While the spread of any new virus can lead to public fear and concern, getting it under control comes from public health intervention and strong leadership from health and government officials while being recognised and reinforced at the public level.
For dental practices, this means strong Policies and Procedures in particular for Standard Precautions including Hand Hygiene and Personal Protective Equipment and Aerosol Management and Quarantine Policies. These, in combination with team accountability and compliant behaviours, will ensure the risk to dental team members and patients is minimised.
A back to basics approach that is team managed is the best way to protect both your practice and your patients. Follow our blogs over the next few weeks to find out more about simple and effective measures to maintain best-practice infection prevention and control at your practice.
Infection Prevention Policy & Procedure Manuals
Dr. Philip Palmer and our team of Infection Prevention & Control Specialists at Prime Practice recommend treating 2019-nCoV like any other viral infection. At home and in the dental practice, ensure thorough Hand Hygiene protocols, cover or catch coughs and sneezes and maintain strong Standard Precautions policies at all times.
Get Safe. Be Safe. Stay Safe.
For credible information and updates:
World Health Organisation
https://www.who.int/emergencies/diseases/novel-coronavirus-2019
Centre for Disease Control
https://www.cdc.gov/coronavirus/
In Australia - Australian Government Department of Health
https://www.health.gov.au/news/coronavirus-update-at-a-glance
In New Zealand - Ministry of Health
https://www.health.govt.nz/our-work/diseases-and-conditions/novel-coronavirus-2019-ncov