You have woken up with a fever and a sore throat. A year ago you would have taken painkillers and you would not have given it more importance, but today the alarms are going off: is it the flu … or COVID? Information from the EFE VERIFY team
With the cold come colds and flu, with symptoms that can be confused with those of COVID-19, so in a health system highly saturated by the pandemic, diagnosis is crucial.
This year, the advancement of the flu vaccination campaign and PCR tests are the only way to take pressure off hospitals and health centers.
What symptoms do they share?
The influenza virus (flu) and SARS-CoV-2 (COVID-19) cause respiratory diseases and some of their most characteristic symptoms are similar: fever, cough, fatigue, shortness of breath, sore throat, runny nose, muscle and headache pain.
Loss of taste and smell, rashes, diarrhea: COVID-19
There are other signs of COVID-19 that flu sufferers do not have, such as loss of taste or smell, skin rashes, or color changes in the fingers or toes.
These are mild symptoms that begin gradually, while fever and cough are usually the first thing the person infected with the new coronavirus experiences.
People with COVID-19 can also have diarrhea, something that children who catch the flu can also get.
Unlike the latter, the infection caused by the coronavirus can rapidly evolve “to serious respiratory problems”, which forces patients to be evaluated from time to time, José Ignacio Peis, of the Spanish Society of Primary Care Physicians, tells EFE (SEMERGEN).
In fact, people who have a fever or cough and also breathe with difficulty, feel pain or tightness in the chest or find it difficult to speak or move have to “call the doctor immediately,” warns the WHO.
And the cold?
Symptoms of the common cold, usually caused by rhinovirus, are easily distinguished because they are much milder than those of the flu and COVID-19 and begin more gradually.
COVID-19: longer incubation time and more contagious
Flu and COVID-19 are transmitted in the same way: through droplets and small particles expelled by coughing or sneezing, as well as by direct contact and with surfaces.
However, this disease is more contagious among certain populations and age groups than the influenza virus and generates many more cases of “super-spreaders”.
After infection, the signs of the disease appear earlier in a person with the flu (one to four days after contracting the infection) than in one with COVID-19.
In the latter case, the disease is revealed around the fifth day after contact with an infected person, but this period of time can vary from two days after contracting the virus to 14.
Recovery and complications
Both the flu and the coronavirus can cause serious complications, especially in older people, with previous pathologies and pregnant women.
In children, however, the flu can cause more serious conditions than COVID-19.
Both diseases can progress with complications such as pneumonia, respiratory failure or heart injury, multi-organ failure, inflammation of the heart, brain, and muscle tissues, and secondary bacterial infections.
The flu usually affects mainly the nose, throat, bronchial tubes, and occasionally the lungs.
But COVID-19 is a disease that not only attacks the respiratory system, but also the immune and cardiovascular system, Peis emphasizes.
In fact, some of these patients develop blood clots in the lungs, heart, legs, or brain; and, in the case of children, there have been cases of multisystemic inflammatory syndrome.
Flu sufferers recover in one to two weeks without the need for medical treatment, usually. In the case of COVID-19, one in five people end up with a serious illness and experience breathing difficulties.
Only the flu has a vaccine
Finally, a key difference between the two diseases is that the flu has a vaccine and COVID-19 does not yet.
Antivirals for influenza reduce the risk of contracting the disease by between 32 and 43%, according to a European study.
In addition to preventing contagion, the vaccine will have a much-needed collateral effect this year: lower healthcare and hospital pressure in the middle of the second wave of coronavirus.
In 2019, these antivirals already prevented 26% of hospitalizations, 40% of ICU admissions and 37% of deaths attributable to the flu, according to the Ministry of Health.
Thus, in order not to compromise more health resources and face the coronavirus pandemic with more guarantees, the 2020-2021 flu vaccination campaign was advanced at the beginning of October.
“In the coming months, SARS-Cov 2 and the flu will coexist and this could especially stress our health system,” said the Secretary of State for Health, Silvia Calzón, at the end of September.
Also the president of the Spanish Association of Vaccination, Amós García Rojas, emphasizes that vaccination “is always important, but there are contexts in which it increases, as in the current pandemic.”
The current pandemic requires that vulnerable groups, such as those over 60, pregnant women, health workers and people with an associated pathology, get vaccinated against the flu to avoid complications in case they contract COVID-19.
Likewise, the Spanish Society of Out-of-hospital Pediatrics and Primary Care (SEPEAP) recommends universal flu vaccination from six months to refine the diagnosis of COVID-19.