The Times Australia
The Times World News

.

Why do I (and my kids) get so many colds? And with all this COVID around, should we be isolating too?

  • Written by Thea van de Mortel, Professor, Nursing and Deputy Head (Learning & Teaching), School of Nursing and Midwifery, Griffith University
Why do I (and my kids) get so many colds? And with all this COVID around, should we be isolating too?

As we head towards winter, the likelihood of picking up a pesky cold increases. But COVID changes how we approach sore throats and runny noses.

If you have cold symptoms and return negative rapid antigen tests, isolating isn’t mandatory – but it’s a good idea. But how long should you stay away from others when you have a cold?

Generally, you’re infectious until your symptoms clear, and should stay away until you’re well again. Passing your cold onto others can mean unnecessary COVID testing for them.

Some people may have a lingering cough or other symptoms when they’re past the normal infectious period. If your RAT is clear for COVID and your symptoms linger, it’s a good idea to consult your GP to rule out other infections or complications.

Read more: Health Check: I feel a bit sick, should I stay home or go to work?[1]

What causes ‘the common cold’?

Unlike other infectious diseases with one specific cause – such as COVID, which is caused by SARS-CoV-2 – the “common cold” is a viral upper respiratory tract infection with a set of classic signs and symptoms, but which is not caused by one specific virus.

Upper respiratory tract graphic.
Common colds affect the upper respiratory tract. Shutterstock[2]

The common cold is most frequently caused by more than 100 different human rhinovirus[3] serotypes (viruses within one species with the same number and type of surface proteins).

Colds can also be caused by multiple other viruses including common cold human coronaviruses[4], parainfluenza viruses[5], adenoviruses and others.

We repeatedly get colds because when we develop immunity to one type of virus that can cause colds, another comes along to which we don’t have immunity. Some of these mutate[6] over time and “escape” from the antibodies we have produced to a previous infection.

While we tend to think of colds as harmless, in the very young[7], the elderly or others with less robust immune systems they can cause serious illness. This can result in hospitalisation[8] and can trigger asthma[9] in susceptible people.

How are colds transmitted?

Cold viruses are transmitted through touching your eyes, mouth, nose or food with hands contaminated by viruses, by direct contact with others, or by inhaling contaminated aerosols.

Pre-school children[10] have six to eight (or more) colds per year.

Children[11] appear to be key drivers of community transmission and bring the infection home from pre-school or school.

Man washes hands with soap.
Good hand hygiene reduces the chance of catching a cold. Shutterstock[12]

Adults then take the infections into their workplaces. Poor ventilation in workplaces[13] may increase the risk of exposure to cold viruses.

Colds are more common[14] in autumn, winter and spring, or in the rainy season if you live in the tropics.

Common cold life cycle

The median incubation period (the most common time it takes to develop symptoms) can vary greatly[15] from about half a day to five and half days, depending on which virus is involved.

In a rhinovirus infection it’s roughly two days[16], although symptoms can occur in as little as half a day.

Generally, you’re likely to be infectious one to two days before developing symptoms[17] and while you have symptoms.

Adults and adolescents usually recover from their symptoms in around seven to ten days[18]. Coughs may last longer[19] for some people, particularly younger children[20].

What symptoms do you get and why?

Inflammation[21] from the infection can cause a number of symptoms, including[22] a sore throat, runny nose, nasal congestion, sneezing and cough.

The runny nose occurs because a chemical called histamine makes your blood vessels more leaky. Your snot starts out clear and runny. Over time it will tend to thicken.

As your immune cells fight off the infection, some white blood cells will die, changing snot colour. As the immune response kicks into high gear, white blood cells called neutrophils produce an infection-fighting chemical (myeloperoxidase) that has a green colour[23].

When lots of neutrophils die in the process of fighting the virus, the myeloperoxidase causes green snot.

If your runny nose persists for an extended period, or you develop facial pain, you may have acquired a sinus infection[24].

Read more: Curious Kids: Why does my snot turn green when I have a cold?[25]

How to prevent catching and transmitting colds

The US Centers for Disease Control and Prevention recommend the following precautions[26] to reduce the risk to others:

  • stay home while symptomatic (and keep sick kids home from school or daycare). For most people, this will be about seven to ten days[27]

  • if you need to cough or sneeze, do so into your elbow. If using tissues, dispose of contaminated tissues and wash your hands afterwards

Child coughs into her arm
Cough into your elbow. Shutterstock[28]
  • wash or sanitise your hands frequently because rhinoviruses can linger on fingers and objects for several hours[29][30]

  • transmission occurs when you’re in close proximity to others. So you may choose to work from home, if possible. If you can’t, keep your distance from your co-workers

  • given aerosol transmission is possible[31], depending on the virus involved, you could also wear a mask at work for a week or two after your symptoms have cleared or if you have returned to work with a lingering cough

  • disinfect frequently touched surfaces.

Finally, train yourself to avoid touching your face. One study[32] compared upper respiratory tract infections in two groups – one that handwashed only, and one that handwashed and used a Smartwatch with a sensor to track hand movements and give reminders about not touching the face.

The group with the hand-tracking and reminders touched their faces less frequently and had a 53% reduction in upper respiratory tract infections.

References

  1. ^ Health Check: I feel a bit sick, should I stay home or go to work? (theconversation.com)
  2. ^ Shutterstock (www.shutterstock.com)
  3. ^ human rhinovirus (www.ncbi.nlm.nih.gov)
  4. ^ common cold human coronaviruses (journals.lww.com)
  5. ^ parainfluenza viruses (onlinelibrary.wiley.com)
  6. ^ mutate (journals.plos.org)
  7. ^ very young (pubmed.ncbi.nlm.nih.gov)
  8. ^ hospitalisation (academic.oup.com)
  9. ^ asthma (www.ncbi.nlm.nih.gov)
  10. ^ Pre-school children (www.thelancet.com)
  11. ^ Children (www.thelancet.com)
  12. ^ Shutterstock (www.shutterstock.com)
  13. ^ Poor ventilation in workplaces (www.proquest.com)
  14. ^ more common (www.thelancet.com)
  15. ^ can vary greatly (www.ncbi.nlm.nih.gov)
  16. ^ two days (www.ncbi.nlm.nih.gov)
  17. ^ infectious one to two days before developing symptoms (emedicine.medscape.com)
  18. ^ seven to ten days (www.cdc.gov)
  19. ^ last longer (emedicine.medscape.com)
  20. ^ younger children (www.rch.org.au)
  21. ^ Inflammation (emedicine.medscape.com)
  22. ^ including (www.thelancet.com)
  23. ^ green colour (www.ncbi.nlm.nih.gov)
  24. ^ sinus infection (www.cdc.gov)
  25. ^ Curious Kids: Why does my snot turn green when I have a cold? (theconversation.com)
  26. ^ recommend the following precautions (www.cdc.gov)
  27. ^ seven to ten days (www.cdc.gov)
  28. ^ Shutterstock (www.shutterstock.com)
  29. ^ and objects (bmcinfectdis.biomedcentral.com)
  30. ^ several hours (pubmed.ncbi.nlm.nih.gov)
  31. ^ aerosol transmission is possible (www.thelancet.com)
  32. ^ One study (ieeexplore.ieee.org)

Read more https://theconversation.com/why-do-i-and-my-kids-get-so-many-colds-and-with-all-this-covid-around-should-we-be-isolating-too-179302

Times Magazine

Headless CMS in Digital Twins and 3D Product Experiences

Image by freepik As the metaverse becomes more advanced and accessible, it's clear that multiple sectors will use digital twins and 3D product experiences to visualize, connect, and streamline efforts better. A digital twin is a virtual replica of ...

The Decline of Hyper-Casual: How Mid-Core Mobile Games Took Over in 2025

In recent years, the mobile gaming landscape has undergone a significant transformation, with mid-core mobile games emerging as the dominant force in app stores by 2025. This shift is underpinned by changing user habits and evolving monetization tr...

Understanding ITIL 4 and PRINCE2 Project Management Synergy

Key Highlights ITIL 4 focuses on IT service management, emphasising continual improvement and value creation through modern digital transformation approaches. PRINCE2 project management supports systematic planning and execution of projects wit...

What AI Adoption Means for the Future of Workplace Risk Management

Image by freepik As industrial operations become more complex and fast-paced, the risks faced by workers and employers alike continue to grow. Traditional safety models—reliant on manual oversight, reactive investigations, and standardised checklist...

From Beach Bops to Alpine Anthems: Your Sonos Survival Guide for a Long Weekend Escape

Alright, fellow adventurers and relaxation enthusiasts! So, you've packed your bags, charged your devices, and mentally prepared for that glorious King's Birthday long weekend. But hold on, are you really ready? Because a true long weekend warrior kn...

Effective Commercial Pest Control Solutions for a Safer Workplace

Keeping a workplace clean, safe, and free from pests is essential for maintaining productivity, protecting employee health, and upholding a company's reputation. Pests pose health risks, can cause structural damage, and can lead to serious legal an...

The Times Features

Duke of Dural to Get Rooftop Bar as New Owners Invest in Venue Upgrade

The Duke of Dural, in Sydney’s north-west, is set for a major uplift under new ownership, following its acquisition by hospitality group Good Beer Company this week. Led by resp...

Prefab’s Second Life: Why Australia’s Backyard Boom Needs a Circular Makeover

The humble granny flat is being reimagined not just as a fix for housing shortages, but as a cornerstone of circular, factory-built architecture. But are our systems ready to s...

Melbourne’s Burglary Boom: Break-Ins Surge Nearly 25%

Victorian homeowners are being warned to act now, as rising break-ins and falling arrest rates paint a worrying picture for suburban safety. Melbourne residents are facing an ...

Exploring the Curriculum at a Modern Junior School in Melbourne

Key Highlights The curriculum at junior schools emphasises whole-person development, catering to children’s physical, emotional, and intellectual needs. It ensures early year...

Distressed by all the bad news? Here’s how to stay informed but still look after yourself

If you’re feeling like the news is particularly bad at the moment, you’re not alone. But many of us can’t look away – and don’t want to. Engaging with news can help us make ...

The Role of Your GP in Creating a Chronic Disease Management Plan That Works

Living with a long-term condition, whether that is diabetes, asthma, arthritis or heart disease, means making hundreds of small decisions every day. You plan your diet against m...