The flu season in T&T runs from October through May.

Still, with the rapid increases in COVID-19 cases and the rise of variants, it can be challenging to determine what is making you feel under the weather.

Both influenza (the flu) and COVID-19 are contagious respiratory illnesses, but they are caused by different viruses. The SARS-CoV-2 virus causes COVID-19, while the flu is caused by infection from influenza viruses. The flu generally causes mild to moderate illness, with few severe or fatal cases in Trinidad and Tobago. In contrast, the far-more-infectious COVID-19 can cause a myriad of outcomes even if you aren’t considered a severe case.

Generally, viruses compete against one another in circulation. We’ve seen this play out as different COVID-19 variants of concern rise to dominance over the last two years.

This also occurs with COVID-19 and influenza (and rhinoviruses that cause the common cold). When COVID-19 cases are high, generally influenza cases are low and vice versa.

As COVID-19 cases surge across T&T, there is a higher chance you may be infected with SARS-CoV-2 rather than the flu.

COVID-19 and the flu can have varying symptoms ranging from appearing perfectly healthy (asymptomatic) to severe cases. Commonly shared symptoms include fever/chills, a cough, shortness of breath or difficulty breathing, fatigue, a sore throat, a runny nose or congestion, muscle pain or body aches, headache, vomiting, and diarrhoea, according to the World Health Organization (WHO) and the United States Center for Disease Control and Prevention (CDC). While common in COVID-19, the change in or loss of smell and taste is possible with influenza infection.

If you are exposed to the flu, typically, you would experience symptoms anywhere from one to four days after infection. COVID-19, on the other hand, can become symptomatic anywhere from two to 14 days after becoming infected. In both cases, you can spread the virus you are infected with at least one day before experiencing symptoms.

Older children and adults with flu appear to be most contagious during the first 3-4 days of their illness, but many remain contagious for about seven days.

For COVID-19, this period of infectivity is still being researched. Until the Omicron COVID-19 variant of concern, research by the CDC showed infectiousness peaks one day before COVID-19 symptoms began but can spread the virus, on average, eight days after symptoms first appeared.

Generally, COVID-19 and the flu spread the same way—person to person who is in close contact (within six feet) by large particles expelled when people, who are ill, cough, sneeze or talk. These particles are inhaled by healthy people into the mouth, nose, throat, and lungs causing infection. People can also be infected by both illnesses by shaking hands with someone who has the virus on their hands or touching a surface or object that has the virus on it and then touching their mouth, nose, or eyes. Importantly, SARS-CoV-2 is far more transmissible than the flu, especially as more transmissible variants spread globally.

In COVID-19 and the flu, the elderly, those with underlying health conditions, and the pregnant population are at most risk. However, with COVID-19, there is a greater risk of healthy people developing severe COVID-19 or even dying from the disease.

From May 1st, 2021 to present, of the 3,189 COVID-19 deaths tracked by Guardian Media, 2,638 had underlying health conditions while 542 were healthy before infection, and for seven, their health issues were not revealed by the Ministry of Health.

Doctors across the world see similar complications from both COVID-19 and the flu in severe cases such as pneumonia, respiratory failure, acute respiratory distress syndrome or where fluid builds in the lungs, sepsis, heart attack, stroke, multiple-organ failure, worsening chronic medical conditions, inflammation of the heart, brain or muscles and secondary bacterial or fungal infections.

While most people recover from the flu within days, with only a few requiring hospitalisations and may need up to two weeks to recover, COVID-19 has a starkly different picture.

COVID-19 can cause blood clots across the body, Multisystem Inflammatory Syndrome in Children and Adults, but people hospitalised due to COVID-19 can remain hospitalised for months. It can take weeks to months for those who recover to have some semblance of normal life after being a severe case.

If you have the flu, drink plenty of water and other clear liquids, take over-the-counter pain relievers if needed and avoid contact with others. If possible, stay home for at least 24 hours after your fever is gone.

Ultimately, many symptoms of both illnesses overlap, so testing and a visit to your doctor will be needed to confirm a diagnosis. There are safe and effective vaccines for both ailments to reduce the risk of hospitalisation and death.

Multiple influenza vaccines are produced annually to protect against the four flu viruses that scientists expect will circulate each year. Numerous COVID-19 vaccines have received WHO’s Emergency Use Authorisation or Emergency Use Listening, proven to reduce the risk of severe COVID-19 and greatly minimise the risk of death.