As September approaches, South Africans continue to feel the chill as the winter respiratory virus season continues, and the flu is still circulating. However, if you wake up with a cough, sore throat, and stuffy nose, it becomes difficult to determine whether it is caused by the flu, COVID-19, or just a common cold.
As temperatures drop in different parts of South Africa, respiratory illnesses are becoming more common. The main issue is that symptoms often overlap, making it difficult to identify the virus causing the illness without testing.
According to the National Institute for Communicable Diseases (NICD), the 2026 flu season in South Africa began in week 9 of March, which is the earliest start recorded since 2010, according to pneumonia surveillance data. NICD reported that the A(H1N1)pdm09 subtype was the most common type of influenza A in pneumonia surveillance and in public clinics, while A(H3N2) predominated in private general practitioner surveillance.
According to the latest NICD Weekly Respiratory Pathogen Surveillance Report, 108 samples were tested, revealing 10 cases of influenza (9.3%), 10 cases of RSV (9.3%), and one case of SARS-CoV-2 (0.9%). NICD notes that the flu season has peaked, but the virus continues to circulate.
What to look out for?
Your main indicator will be the speed of disease onset. The flu typically comes on suddenly and intensely, unlike a common cold. A person with the flu can go from feeling well to extremely unwell within a few hours, accompanied by fever, chills, body aches, headache, cough, and fatigue.
People with colds experience milder symptoms and are more likely to have tissues due to a runny or stuffy nose. Sneezing and sore throat may also occur. The CDC indicates that cold symptoms are usually less intense than flu symptoms, and people with colds are more likely to suffer from a runny or stuffy nose.
The situation is complicated by the fact that COVID-19 can mimic any of these viruses. The World Health Organization (WHO) states that COVID-19 and influenza can cause symptoms such as cough, runny nose, sore throat, fever, headache, and fatigue.
Common cold symptoms
Common cold symptoms may include a runny or stuffy nose, sneezing, sore throat, cough, mild headache, slight body aches, and tiredness. Colds are generally less severe than the flu and less likely to lead to serious complications.
Flu symptoms
The flu usually causes sudden fever or feeling feverish, chills, cough, sore throat, runny or stuffy nose, headache, muscle and body aches, and fatigue. NICD lists the sudden onset of fever, muscle aches, body aches, dry cough, sore throat, runny nose, and fatigue among common flu symptoms. It should be noted that not everyone who gets the flu will have a fever.
COVID-19 symptoms
COVID-19 can cause fever or chills, cough, sore throat, fatigue, headache, body aches, runny or stuffy nose, loss or change of taste or smell, shortness of breath, nausea or vomiting, and diarrhea. The range of symptoms varies among individuals, and many cases are mild.
Can flu and COVID-19 be distinguished by symptoms?
No. According to the WHO, it is impossible to distinguish between the flu and COVID-19 based on symptoms alone. Testing is the only way to determine which virus is responsible, or if a person has both infections. The CDC also states that flu and COVID-19 symptoms overlap, and testing is required to confirm the diagnosis.
This means that a high temperature and body aches do not necessarily indicate the flu, and a stuffy nose and sore throat do not necessarily mean a cold.
When should I get tested for COVID-19?
Consider getting tested if you have symptoms similar to a cold or flu and suspect you have COVID-19, especially if you belong to a high-risk group for severe illness. The CDC advises people with cold-like symptoms who suspect COVID-19 or flu to get tested, particularly those in a high-risk group for severe illness.
Testing is also useful if you have recently been in contact with someone who has COVID-19, or if you are about to be near a vulnerable person susceptible to severe respiratory illness. There are also tests capable of detecting more than one respiratory virus. The CDC notes that at-home multiplex tests can detect both COVID-19 and flu in one test.
What if a COVID-19 test is negative? A negative result does not necessarily mean your symptoms are caused by a common cold. This is because depending on the type of test and when it is performed, the infection may not be detected. If symptoms persist or worsen, especially if you belong to a high-risk group for severe illness, consult a healthcare professional about the advisability of further testing.
What about flu testing?
Influenza can also be diagnosed through tests, although sometimes a healthcare provider may make a clinical diagnosis based on symptoms, patient risk factors, and whether the flu is circulating. This is especially important for people at high risk of complications, as antiviral treatment for the flu is most effective when started early. The NICD's 2026 flu guidelines state that antiviral treatment should be considered for people with severe flu and those in a high-risk group for complications, with treatment being most effective when started as soon as possible.
When should I see a doctor?
Most people with mild respiratory infections recover without hospitalization, but you should seek medical attention if symptoms become severe or rapidly worsen. Emergency medical care is necessary for symptoms such as difficulty breathing or severe shortness of breath, chest pain or pressure, confusion or difficulty staying awake, severe weakness, signs of severe dehydration, and symptoms that improve and then suddenly worsen.
People in a high-risk group for severe illness should also contact a healthcare professional early if they develop symptoms resembling the flu or COVID-19.
Do not spread the illness
If you are sick, try to avoid close contact with other people, especially the elderly, young children, and people with underlying conditions who put them at greater risk of severe respiratory illness. Improving ventilation in the home, regular handwashing, covering coughs and sneezes, and wearing a mask in crowded indoor settings can help reduce the spread of respiratory viruses.
