Support from readers like you keeps The Journal open.
You are visiting us because we have something you value. Independent, unbiased news that tells the truth. Advertising revenue goes some way to support our mission, but this year it has not been enough.
If you've seen value in our reporting, please contribute what you can, so we can continue to produce accurate and meaningful journalism. For everyone who needs it.
PEOPLE ACROSS THE country have been severely restricting their movements for over two weeks now following Government measures aimed at slowing the spread of the Covid-19 coronavirus.
The goal is to reduce contact and transmission of the virus but those working on the frontline of healthcare such as doctors and nurses, and those drafted in from other sectors such as defence and education to support healthcare staff, do not have the luxury.
They are working in hospital and healthcare settings where the virus is present and so to reduce the risk of that cohort of the population contracting the virus, significant resources have been put behind securing and rolling out personal protective equipment, or PPE.
On Sunday the first delivery of PPE from China – one of ten flights which were scheduled to land over the past four days – arrived on board an Aer Lingus flight and were due to be dispersed to over 2,000 locations around the country that same day.
In the meantime, comments across social media and from healthcare workers themselves, have pointed to concerns that those working on the frontline who contract the virus will experience more severe symptoms than the general population due to the “viral load” being greater.
But what exactly is the viral load, which is different to the initial infection source known as the infectious dose, and is there any truth behind social media claims that healthcare workers will experience worse symptoms than the general population?
There is no simple yes or no answer to this question as Kim Roberts, a virologist at Trinity College Dublin, explained.
“If you’re exposed to a large amount of a virus it can lead to a more severe infection but the severe infection is multifactorial and multiple things play a role.
“Your own health and immune system come into play and there is a host of other things. That’s where PPE comes in and that PPE is all about reducing the chance that the virus they are in contact with will actually infect them.”
Let’s start from the beginning – what is a viral load?
A viral load is the total amount of virus that a person has inside them. An easy way to think about a viral load is through the treatment of another virus – the Human Immune Virus (HIV).
In recent years, new retroviral drugs have been developed which have been able to almost completely eliminate the presence – or viral load – of HIV in the bloodstream of a person who has contracted it.
If a person was to stop taking those drugs, the human immune virus would begin to replicate at a rapid pace and the presence of it in a person would multiply i.e the viral load would increase, putting pressure on the human immune system.
Similarly, when someone contracts the Covid-19 virus, that virus begins to replicate and strengthen its hold in a person’s body. That’s when the immune system kicks in and begins its efforts to fight it off.
A person’s ability to fight the replication of the virus then depends on how healthy they are and how strong their immune system is.
The weaker the immune system, the greater the chance it has to replicate and so the greater the chance of the viral load increasing, and symptoms associated with the virus becoming more severe.
Advertisement
But this is different from the initial ‘infectious dose’.
The infectious dose refers to the number of virus particles exposed during transmission and the amount of those which is needed for the virus to infect a person. But this has incorrectly been conflated with the meaning of the ‘viral load’ recently.
When a virus is transmitted from one person to another, it means hundreds, or thousands of particles in the case of some viruses, are transmitted from one person to another – usually through a cough or a sneeze.
Many of those particles will be suppressed by a person’s immune system once they reach the body – but some will make it through and subsequently infect a cell, where it can begin to replicate.
As healthcare workers are working in closer proximity to people with the virus than those in the general population, they are exposed to these particles more often – and in greater amounts – so the likelihood of infection increases.
“The minimum infectious dose is how many virus particles you can be exposed to in order to trigger a viral infection, and we don’t know what it is in the case of Covid-19 yet. It varies from one virus to another,” Roberts explained.
And when a person, hospitalised due to the virus, coughs or sneezes, they release much greater numbers of virus particles than those in the general population who might be experiencing milder symptoms.
“It’s all about probability and it’s the probability that you are exposed to enough of the virus so that one particle can fight through those respiratory and other barriers, other natural barriers that we have, so it can get into a cell,” Roberts said.
“All it takes is one virus particle to get to the cell and it will replicate but your body still has a system to suppress the virus.
It’s down to the immune system of that person because they might have had a small infectious dose but their immune system might not have had the resources to stop it.
And as Dr Michael Skinner of Imperial College London points out here, “It is unlikely that higher doses that would be acquired by being exposed to multiple infected sources would make much difference to the course of the disease or the outcome.”
What does this mean for healthcare staff?
It means the severity of the symptoms experienced by anyone who contracts the virus, including healthcare workers, is down to the individual immune response, and other factors such as weakened immune systems, underlying conditions etc.
The likelihood of contracting the virus in the first place, however, is heightened, but employing PPE, repeated hand-washing, and other protocols can significantly reduce that from happening.
It is also worth noting that while one in four cases – 841 of the 3,849 confirmed cases – of the virus in Ireland have been identified in healthcare workers, much of those were cited as occurring due to travel, with fewer than a quarter of those workers contracting the virus in a healthcare setting.
The HSE and Department of Health have issued guidelines for frontline staff around using personal protective equipment, and this is the easiest way to reduce the likelihood of healthcare workers contracting the virus.
“Good infection prevention and control (IPC) practice, supported by appropriate use of PPE is important to minimise the risk of exposure to occupational infections for healthcare workers (HCWs),” a spokesperson said.
There is also a range of videos here demonstrating how PPE should be used.
Readers like you are keeping these stories free for everyone...
Our Explainer articles bring context and explanations in plain language to help make sense of complex issues.
We're asking readers like you to support us so we can continue to provide helpful context to everyone, regardless of their ability to pay.
TheJournal.ie's Coronavirus Newsletter
TheJournal.ie's coronavirus newsletter cuts through the misinformation and noise with the clear facts you need to make informed choices. Sign up here
To embed this post, copy the code below on your site
Close
16 Comments
This is YOUR comments community. Stay civil, stay constructive, stay on topic.
Please familiarise yourself with our comments policy
here
before taking part.
When the world eventually gets this dangerous virus under control ! it will never be same again particular Europe /American/all other western nations will need to look very carefully at manufacturing our own medical /engineering /all other important products for nation security at times of crisis and greatly reduced our dependency on China and other like minded states!
@Bobby wilson:
Maybe all those nations at war, who spend significant amounts of money on weaponry, could instead put it towards the health and welfare of their citizens.
I’m thinking particularly of African nations, the Taliban in Afghanistan, Iran and Iraq.
Maybe, just maybe this is a wake up call for humanity across the entire world!
@Mary Walshe: “a wake up call for humanity across the entire world!”
I’d like to think so but we’ve had two world wars in the last 100 years that killed over 100 million people and we carried on as before both times (more or less).
We have short memories.
@Mary Walshe: There are multiple potential threats that we face – pandemics is just one of them. Bio-terrorism, cyber terrorism or outright military conflicts, natural disasters (massive volcanic eruption is one big one) and climate change are other threats. Europe has become complacent since WWII, thinking that we are immune from external and internal threats and that material progress is an inevitability. This virus has shown this isn’t true. We should take this as a lesson and make proper contingencies for future threats – and yes includes potential future military threats. We’re lucky that this virus isn’t much more deadly, a contagious virus with a mortality rate of 30-40% or more is certainly possible.
Bearing this article in mind ,I am very concerned with the article in IT’s 2 days ago:’Some protection equipment from China ” not ideal”,HSE says’.This shipment cost over €208m but more concerned about the safety of frontline staff!
@Nuala Mc Namara: all the more reason why western nations must come together after this nightmare end. Start manufacturing our own medical /engineering /all other important nation security equipment. even it cost more to produce a least it will be of higher quality. Let’s Greatly reduced our dependency on China and other fellow totalitarian states in the world!
@Nuala Mc Namara: heard on RTE news that most of the equipment isn’t faulty it’s just not what our hospitals are use too using, most will have to be retrained
@Bobby wilson: yeah the 17% now unemployed can work in our new factories I’m sure we can pay them a few more euro than the slave labour our chinese counterparts get.
@Alan Watts: yes! And At least it will be of higher quality than some of equipment made in those states in the far east!..this will be different world when this virus is put under control particular western nations that includes [brixit Britain ] Europe/EU/USA/must all come back together and work closely as one in developing better food/medical /engineering security equipment in coming years and not depending on totalitarian states across the world!
@Nuala Mc Namara: I heard that not ideal but good enough although they have now changed the order…
So if RTE says good enough then they must be good enough…Odd way of explaining it though was being very carefull with his words and looked stressed trying to explain without explaining properly.. Weird..
The jury is very much out on initial dose and severity of symptoms. In influenza SARS and MERS there is a correlation and it is highly likely that COVID19 is the same. Even in the discussion that you linked from the science media centre more of the opinions seemed to fall on the side that initial dose is a factor in outcome. More balance please author!
'Really stupid move': Dublin councillors are fighting over giving Obama the keys to the city
4 hrs ago
4.4k
70
Investigation
Online retailer Temu potentially in breach of EU digital marketplace rules
6 hrs ago
4.6k
Maguiresbridge
Fourth person dies following fatal shooting of mother and children in Co Fermanagh last week
8 hrs ago
75.0k
Your Cookies. Your Choice.
Cookies help provide our news service while also enabling the advertising needed to fund this work.
We categorise cookies as Necessary, Performance (used to analyse the site performance) and Targeting (used to target advertising which helps us keep this service free).
We and our 214 partners store and access personal data, like browsing data or unique identifiers, on your device. Selecting Accept All enables tracking technologies to support the purposes shown under we and our partners process data to provide. If trackers are disabled, some content and ads you see may not be as relevant to you. You can resurface this menu to change your choices or withdraw consent at any time by clicking the Cookie Preferences link on the bottom of the webpage . Your choices will have effect within our Website. For more details, refer to our Privacy Policy.
We and our vendors process data for the following purposes:
Use precise geolocation data. Actively scan device characteristics for identification. Store and/or access information on a device. Personalised advertising and content, advertising and content measurement, audience research and services development.
Cookies Preference Centre
We process your data to deliver content or advertisements and measure the delivery of such content or advertisements to extract insights about our website. We share this information with our partners on the basis of consent. You may exercise your right to consent, based on a specific purpose below or at a partner level in the link under each purpose. Some vendors may process your data based on their legitimate interests, which does not require your consent. You cannot object to tracking technologies placed to ensure security, prevent fraud, fix errors, or deliver and present advertising and content, and precise geolocation data and active scanning of device characteristics for identification may be used to support this purpose. This exception does not apply to targeted advertising. These choices will be signaled to our vendors participating in the Transparency and Consent Framework. The choices you make regarding the purposes and vendors listed in this notice are saved and stored locally on your device for a maximum duration of 1 year.
Manage Consent Preferences
Necessary Cookies
Always Active
These cookies are necessary for the website to function and cannot be switched off in our systems. They are usually only set in response to actions made by you which amount to a request for services, such as setting your privacy preferences, logging in or filling in forms. You can set your browser to block or alert you about these cookies, but some parts of the site will not then work.
Social Media Cookies
These cookies are set by a range of social media services that we have added to the site to enable you to share our content with your friends and networks. They are capable of tracking your browser across other sites and building up a profile of your interests. This may impact the content and messages you see on other websites you visit. If you do not allow these cookies you may not be able to use or see these sharing tools.
Targeting Cookies
These cookies may be set through our site by our advertising partners. They may be used by those companies to build a profile of your interests and show you relevant adverts on other sites. They do not store directly personal information, but are based on uniquely identifying your browser and internet device. If you do not allow these cookies, you will experience less targeted advertising.
Functional Cookies
These cookies enable the website to provide enhanced functionality and personalisation. They may be set by us or by third party providers whose services we have added to our pages. If you do not allow these cookies then these services may not function properly.
Performance Cookies
These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. They help us to know which pages are the most and least popular and see how visitors move around the site. All information these cookies collect is aggregated and therefore anonymous. If you do not allow these cookies we will not be able to monitor our performance.
Store and/or access information on a device 149 partners can use this purpose
Cookies, device or similar online identifiers (e.g. login-based identifiers, randomly assigned identifiers, network based identifiers) together with other information (e.g. browser type and information, language, screen size, supported technologies etc.) can be stored or read on your device to recognise it each time it connects to an app or to a website, for one or several of the purposes presented here.
Personalised advertising and content, advertising and content measurement, audience research and services development 195 partners can use this purpose
Use limited data to select advertising 158 partners can use this purpose
Advertising presented to you on this service can be based on limited data, such as the website or app you are using, your non-precise location, your device type or which content you are (or have been) interacting with (for example, to limit the number of times an ad is presented to you).
Create profiles for personalised advertising 119 partners can use this purpose
Information about your activity on this service (such as forms you submit, content you look at) can be stored and combined with other information about you (for example, information from your previous activity on this service and other websites or apps) or similar users. This is then used to build or improve a profile about you (that might include possible interests and personal aspects). Your profile can be used (also later) to present advertising that appears more relevant based on your possible interests by this and other entities.
Use profiles to select personalised advertising 120 partners can use this purpose
Advertising presented to you on this service can be based on your advertising profiles, which can reflect your activity on this service or other websites or apps (like the forms you submit, content you look at), possible interests and personal aspects.
Create profiles to personalise content 51 partners can use this purpose
Information about your activity on this service (for instance, forms you submit, non-advertising content you look at) can be stored and combined with other information about you (such as your previous activity on this service or other websites or apps) or similar users. This is then used to build or improve a profile about you (which might for example include possible interests and personal aspects). Your profile can be used (also later) to present content that appears more relevant based on your possible interests, such as by adapting the order in which content is shown to you, so that it is even easier for you to find content that matches your interests.
Use profiles to select personalised content 48 partners can use this purpose
Content presented to you on this service can be based on your content personalisation profiles, which can reflect your activity on this or other services (for instance, the forms you submit, content you look at), possible interests and personal aspects. This can for example be used to adapt the order in which content is shown to you, so that it is even easier for you to find (non-advertising) content that matches your interests.
Measure advertising performance 177 partners can use this purpose
Information regarding which advertising is presented to you and how you interact with it can be used to determine how well an advert has worked for you or other users and whether the goals of the advertising were reached. For instance, whether you saw an ad, whether you clicked on it, whether it led you to buy a product or visit a website, etc. This is very helpful to understand the relevance of advertising campaigns.
Measure content performance 78 partners can use this purpose
Information regarding which content is presented to you and how you interact with it can be used to determine whether the (non-advertising) content e.g. reached its intended audience and matched your interests. For instance, whether you read an article, watch a video, listen to a podcast or look at a product description, how long you spent on this service and the web pages you visit etc. This is very helpful to understand the relevance of (non-advertising) content that is shown to you.
Understand audiences through statistics or combinations of data from different sources 111 partners can use this purpose
Reports can be generated based on the combination of data sets (like user profiles, statistics, market research, analytics data) regarding your interactions and those of other users with advertising or (non-advertising) content to identify common characteristics (for instance, to determine which target audiences are more receptive to an ad campaign or to certain contents).
Develop and improve services 116 partners can use this purpose
Information about your activity on this service, such as your interaction with ads or content, can be very helpful to improve products and services and to build new products and services based on user interactions, the type of audience, etc. This specific purpose does not include the development or improvement of user profiles and identifiers.
Use limited data to select content 51 partners can use this purpose
Content presented to you on this service can be based on limited data, such as the website or app you are using, your non-precise location, your device type, or which content you are (or have been) interacting with (for example, to limit the number of times a video or an article is presented to you).
Use precise geolocation data 65 partners can use this special feature
With your acceptance, your precise location (within a radius of less than 500 metres) may be used in support of the purposes explained in this notice.
Actively scan device characteristics for identification 36 partners can use this special feature
With your acceptance, certain characteristics specific to your device might be requested and used to distinguish it from other devices (such as the installed fonts or plugins, the resolution of your screen) in support of the purposes explained in this notice.
Ensure security, prevent and detect fraud, and fix errors 122 partners can use this special purpose
Always Active
Your data can be used to monitor for and prevent unusual and possibly fraudulent activity (for example, regarding advertising, ad clicks by bots), and ensure systems and processes work properly and securely. It can also be used to correct any problems you, the publisher or the advertiser may encounter in the delivery of content and ads and in your interaction with them.
Deliver and present advertising and content 126 partners can use this special purpose
Always Active
Certain information (like an IP address or device capabilities) is used to ensure the technical compatibility of the content or advertising, and to facilitate the transmission of the content or ad to your device.
Match and combine data from other data sources 94 partners can use this feature
Always Active
Information about your activity on this service may be matched and combined with other information relating to you and originating from various sources (for instance your activity on a separate online service, your use of a loyalty card in-store, or your answers to a survey), in support of the purposes explained in this notice.
Link different devices 67 partners can use this feature
Always Active
In support of the purposes explained in this notice, your device might be considered as likely linked to other devices that belong to you or your household (for instance because you are logged in to the same service on both your phone and your computer, or because you may use the same Internet connection on both devices).
Identify devices based on information transmitted automatically 116 partners can use this feature
Always Active
Your device might be distinguished from other devices based on information it automatically sends when accessing the Internet (for instance, the IP address of your Internet connection or the type of browser you are using) in support of the purposes exposed in this notice.
Save and communicate privacy choices 103 partners can use this special purpose
Always Active
The choices you make regarding the purposes and entities listed in this notice are saved and made available to those entities in the form of digital signals (such as a string of characters). This is necessary in order to enable both this service and those entities to respect such choices.
have your say