Flu Season, Symptoms, and Lupus

Flu season means more than just a higher risk of getting the flu for people with lupus.

Systemic lupus erythematosus (SLE) is an autoimmune disease. In autoimmune diseases, the immune system, which normally protects the body from pathogens, attacks the body instead and causes the symptoms of lupus. However, because the immune system is busy causing damage, it sometimes can fail to defend the body against real threats. 

“Flu Season,” which starts around October and ends around May, is the time of year when people are most likely to catch the flu. Flu infections generally reach their height in February, and then decrease as the seasons change to spring. Flu season, which includes winter and fall, also includes higher rates of other diseases and many unique challenges for people with lupus.

What is the Flu Like?

Influenza, also known as the flu, is a respiratory disease caused by a virus. The flu is seasonal, occurring in the Fall and Winter.

Symptoms include a

• high fever
• aches and pains
• shaking
• headache
• fatigue
• sore throat
• cough
• runny nose

It can lead to pneumonia or other infections in people with weakened immune systems, including people with lupus who take immune system suppressant drugs. 

The flu shot, a vaccination that helps the body fight off the flu virus, reduces the severity of flu symptoms, reduces the risk of serious infection, and helps prevent people who catch the flu from passing it on. People with lupus are generally recommended to get the flu shot to help make up for their weakened immune system. You can read more about flu shots (including the nasal spray,) and lupus here. 

What Happens to People with Lupus During Flu Season?

In a 2021 study, researchers looking at information from the Korean national healthcare insurance database found that the influenza, or flu virus can also trigger lupus flares. This means that, in addition to having higher risks of complications from the flu, people with lupus were estimated to be at about 25.75% higher risk. This might not be the true number, due to the limits of the study, but it is clear that influenza infection can trigger symptom flares, making it extra important for people with lupus to take precautions against the flu. However, during the flu season months, people with lupus also face other challenges, including:

• Increased cold weather and joint pain.
• Dryer air and, thus, dryer mouths and eyes.
• Lower levels of sunlight, which can lead to vitamin D deficiency. you can read more about vitamin D here. 
• Other diseases, which are more easily spread due to people staying inside in close quarters with each other.
• Sun exposure (especially near snow or water) can be intense enough, even in the winter, to trigger UV-light-related flares. 

You can read more about how people with lupus get sick here.

A drier mouth and nose limit the body’s ability to prevent pathogens, including bacteria and viruses, from entering the body. Normally, even if a virus does get through the outer defenses of the body, the numbers are small enough to keep the rate of successful infection low. However, viruses also like cooler temperatures and replicate more, making them much more likely to cause illness when they appear. There is some evidence that cold, about 25-33 degrees Celsius, makes the immune system less efficient. This should be taken with a grain of salt, however, since the human body maintains itself a constant temperature of roughly 37 degrees Celsius. Since most of the immune system’s activity is inside the body, this means that the immune system cells are not coming into contact with the cold of the outside world.

Cold weather can also increase the risks of heart problems according to the American Heart Association. Air temperature is a major part of this, with colder weather leading to an increased risk of myocardial infarctions (MI, or heart attacks.) However, other factors of ‘flu season,’ such as low sunshine and windy weather, increase these risks as well. Fluctuations in air pressure, which happen often in the fall and winter months, were also associated with increased risks of heart attacks. These also can cause headaches and feelings of fatigue and fogginess, which can make already existing fatigue and brain fog worse. You can read more about lupus and the weather here. 

How to Get Through Flu Season with Lupus

People with lupus want to avoid catching the flu or other illnesses. Since they are more likely to have greater symptoms, they also have a possibility of being hospitalized. This is something to avoid, since not only are hospitals extra busy at this time of year, but they can also be hotbeds for other illnesses. You can read more about hospitalization and lupus here.

Wearing face masks, staying away from large groups of people, and washing hands frequently greatly lowers the risk of catching the flu, as well as other diseases. Sunscreen can help with the sun exposure, and a humidifier can help improve dry air. The vaccine is important, as it protects people with lupus from the symptoms of the flu and the potential for lupus flares. It also protects anyone coming into contact with them because they are less likely to spread the disease to others. 

People with lupus should also generally keep themselves warm and cozy. Dressing warmly, with layers, helps, but it can be equally important to be moving around actively outdoors, which helps keep the blood flowing to the joints and warming them. 

You can read more about dealing with pain and lupus during wintertime here.

What to do After Flu Season

Winter and fall bring many challenges for people with lupus, but when flu season is over and spring arrives, people with lupus have a whole different set of problems to deal with. The sun during the spring and especially summer is more intense, and hot weather can increase inflammation and symptoms of lupus. This is part of the reason why skin symptoms and joint pain are more problematic in the spring and summer. Wearing high-spf sunscreen is also highly recommended.

Flu season is also a bit of a misnomer – influenza circulates throughout the year, and people can and do get sick from it outside of “flu season.” People with lupus should continue to use protective gear such as masks and wash their hands and surfaces thoroughly. You can read more about the importance of keeping clean with lupus here.