Image source, Getty Images
At BBC headquarters, there is a sense that friends, colleagues and family have had a tougher year than usual: catching one cold and then quickly catching another, jumping from one infection to another.
“The reality is we have a lack of data and so we have a lot of anecdotes,” says Professor Jonathan Ball, of the Liverpool School of Tropical Medicine.
So what could happen?
It’s a Covid summer
We’re in a summer wave of Covid, so if you have a cough or fever, the virus is a possible culprit.
We’re not collecting the same detailed data as we did at the peak of the pandemic, but the wave started to build around May.
“I know so many people who have recently had Covid,” says Professor Peter Openshaw of Imperial College London.
About 3,000 people in hospital have now tested positive for Covid-19, about double the figure from early April. The infection is not necessarily the reason for their hospital admission, but it is a way of assessing whether we are in a wave.
“There is a very significant increase, Covid has not yet turned into a winter virus, we can say that with great confidence,” says Professor Openshaw.
This appears to be due to the FLiRT variants of the virus and pubs full of football fans may have also given the virus a helping hand.
The virus is still capable of causing a nasty infection and although we are no longer taking emergency measures to control it, we are administering two doses of vaccine per year to the most vulnerable because of the threat it can pose.
Disrupted seasons
Most respiratory infections (coughs, colds and flu) are likely to be contracted during the winter months.
Cooler weather, spending more time indoors and keeping windows closed are all factors that give these respiratory viruses an advantage this time of year.
One argument is that pandemic restrictions have disrupted this usual pattern (the flu almost disappeared during some winter lockdowns) and things are not yet quite back to normal.
“It seems to have disrupted the seasonality, particularly the cold viruses, so they were appearing at odd times and I don’t think things have stabilised yet, there’s a bit of catching up to do,” says Professor Ball.
The idea is that even if you get exactly the same number of infections over the course of a year, you might feel like you’re sick all the time.
“These kinds of things prolong that period of time when we feel groggy and so we’re going to think, ‘I’m sicker than I was before,'” suggests Professor Ball.
Image source, Getty Images
Whooping cough
We also saw the resurgence of whooping cough – also known as 100-day cough or pertussis – in 2024.
An outbreak of this bacterial infection occurs every three to five years, but the last one was in 2016.
So there probably should have been an outbreak during the peak years of the pandemic.
The UK Health Security Agency warns: “The impact of the pandemic also means a decline in immunity within the population.”
Symptoms are similar to a cold with a runny nose and sore throat that progress to coughing fits, which can last a long time, hence the nickname 100 days.
Anyone can get whooping cough, but it is usually mild in adults. The problem is that they can pass it on to babies, who are very vulnerable. Nine people have died from the disease this year.
This is why newborn vaccines and the whooping cough vaccine during pregnancy (which gives protective antibodies to the baby while it is still in the womb) are so important, but…
Vaccination rates have fallen
Lower vaccination levels mean more people are contracting preventable diseases.
Take whooping cough, for example: 72.6% of pregnant women chose to be vaccinated in March 2017. The figures for March 2024 were 58.9%.
But the decline in vaccination is a broader trend for childhood vaccines. The UK met the target of 95% of children vaccinated against measles, mumps and rubella for the first time in 2017, but that figure has now fallen to 92.5%.
“We have more susceptible people and that increases the ability of these infections to thrive, which is why we have had warnings about measles outbreaks,” says Professor Sheena Cruickshank of the University of Manchester.
Outbreaks of measles have been reported in Birmingham and London. Initial symptoms resemble those of a cold (fever, runny nose, cough) before a rash appears.
This has led experts to call for an “urgent reversal” of falling vaccination numbers, as we reach a tipping point where children are dying or becoming seriously ill from preventable diseases.
More vulnerable to infection
Another idea is that even if the microbes in circulation did not change, we would have become more vulnerable to their presence because our general health is fragile after austerity, a pandemic and a cost of living crisis.
According to Professor Cruickshank, stress makes the immune system “less able to function” and sedentary lifestyles and poor diet cause “metabolic inflammation”.
“This is where our immune system becomes imbalanced and it makes us less able to effectively deal with threats,” she explains.
“Many of us are malnourished and lacking essential nutrients that are really important for our immune system.”
So infections that our bodies could have easily cleared in the past can cause more intense symptoms today.
Hay fever
If you’re feeling unwell with a runny nose, itchy throat and sneezing fits, it may be your immune system reacting to the pollen rather than an infection.
“If you’re unlucky enough, like me, to have hay fever, it won’t make you feel particularly good either,” she says.
According to the Met Office, climate change could impact hay fever by increasing the pollen season and pollen intensity, making hay fever worse and longer lasting.
This is a long-term trend, but Professor Cruickshank believes it could explain why people are feeling “a little less well” this summer.
Summer colds are nothing new.
The term “summer cold” was not invented in 2024.
Professor Ball says that in addition to the other factors mentioned above, we may also be more nervous about coughs and colds after developing a “heightened” response due to the pandemic.
In 2019, no one asked “is it Covid?” when a colleague had a hacking cough or “should I buy a Covid test?” when feeling tired before a holiday flight or a visit to elderly relatives.
“People are a little more aware of colds and other issues that, before the Covid-19 pandemic, allowed them to continue their lives as normal,” says Professor Ball.
Covid is still Covid, but maybe we don’t need to worry so much about a good old summer cold.