Flu season is beginning. It usually starts in the fall (October) and extends through the spring (April/May). Each year, millions of people get the flu. Missed school and work can be quite significant, but also hundreds of thousands of people need to be hospitalized and tens of thousands die from flu-related complications.
While many people call any upper respiratory infection "the flu," it is actually specific to an infection from the influenza virus. Typical symptoms include sudden onset fever, chills, cough, runny nose, muscle aches, headaches, and fatigue. Vomiting and diarrhea can occur, but more often occur in children. It is important to note that not everyone with the flu will have a fever. The typical cold differs from the flu in that the common cold is usually more gradual in onset, is less likely to have fever, chills, and headaches, has less severe muscle aches; the flu is more often characterized by sneezing, stuffy nose, and sore throat. Symptoms usually resolve within a few days to less than two weeks.
Anyone can get the flu, but there are certain high-risk groups that are more likely to develop severe symptoms or complications that can potentially be life-threatening. Individuals older than 65 years, babies and young children, those with chronic medical conditions, such as asthma, heart problems, or diabetes, and pregnant women are some of the highest-risk groups.
The flu is highly contagious and is usually spread by droplets after someone with the flu sneezes, coughs, or even speaks to someone up to six feet away. The virus can be spread one day before and up to five to seven days after symptoms begin, which means the flu can spread before someone even knows they are sick! Frequent handwashing with soap or alcohol-based sanitizers, avoidance of contact with sick persons, and not sharing dishes and utensils are important prevention tactics.
Vaccination is the most effective way of preventing oneself and others from getting the flu. Antibodies form about two weeks after the vaccine is given and provide protection from the viruses that are in the vaccine. Each year, based on extensive research, the three to four strains of influenza virus that are expected to be most common are used for the vaccine. It is still possible to get the flu after vaccination if the strains in the community are not closely matched to the ones in the vaccine. However, any flu shot can protect against severe complications and hospitalization. It can also decrease the severity of one’s symptoms. Most importantly, it creates herd immunity by protecting those who cannot receive the vaccine from getting sick. Medical care providers and those with very young children should specifically be encouraged, if not required, to be vaccinated.
Anyone older than six months of age should receive the injectable vaccine. The nasal spray, however, is not recommended for use this year. Ideally, people should receive the vaccine early in the season (by the end of October). Children receiving the vaccine for the first time require a second dose, so most pediatricians try to give the first dose in the beginning of October so the second dose can be given one month later before getting too far into flu season. Those with an egg allergy can be given the vaccine if administered in a clinical setting (hospital or physician’s office). Those with a prior severe allergy to the vaccine should not receive the vaccine. Anyone with a history of a severe illness called Guillain-Barré Syndrome (GBS) should discuss vaccination with their physician.
If someone develops symptoms of the flu, they should be examined and possibly tested for influenza as soon as possible, as anti-viral medications can be effective in improving symptoms if given within 72 hours of symptom onset. These medications can decrease the length of illness and prevent severe complications and hospitalization, especially in the highest-risk groups.
If anyone has specific questions regarding the flu and vaccination, I encourage you to contact your physician. Wishing everyone a happy and healthy year!
By Jared Hershenson
Jared Hershenson, MD, is a pediatric cardiologist with expertise in general pediatric cardiology, fetal cardiology, and sports cardiology. He is the director of the exercise physiology lab at Child Cardiology Associates, which has offices throughout Maryland and Northern Virginia.