Influenza – What You Need to Know
We have all been there – its winter and all of the sudden we are coughing, don’t feel well and wonder “Do I have the flu?”
Influenza season tends to start in October and can sometimes drag on into May. Influenza usually starts with fever, headache, body aches, cough and just feeling ill. It can progress to involve nasal congestion and runny nose, sore throat and for some, nausea and vomiting. It is important to note that “the flu” refers to Influenza, not to viruses that have vomiting and diarrhea as their main symptoms. Confusion arises when people refer to this intestinal illness as “the stomach flu.” True, influenza is primarily a respiratory illness which can help to tell the difference between the two. Many people who get influenza will recover within 3-7 days with or without treatment, but for some dangerous complications can occur. These include viral or bacterial pneumonia, exacerbations of underlying lung or heart conditions, or in some cases even death.
So, how do you get influenza? Since it is a respiratory illness, it’s mainly spread through contact with respiratory droplets of someone who has influenza, but it can also be picked up from contaminated surfaces. Someone may not even know that they are sick, but can still infect others because you are contagious with influenza up to 24 hours before symptoms start. After 5-7 days you will no longer spread the virus, and after being exposed it can take 1-4 days for you to become sick. You can help prevent the spread of illness by good hand washing, cleaning contaminated surfaces, avoiding people who are ill and getting a flu shot.
Everyone probably knows someone who has “gotten the flu from the flu shot.” In the past there were two main forms of influenza vaccine, one was a shot and one was an intranasal (“mist”) preparation.
During this influenza season, only shots will be available in the United States as the mist was not as effective as hoped in the last three flu seasons. The shot contains a fully killed virus and can cause mild symptoms similar to a cold, but rarely give symptoms as severe as the influenza virus you can catch from others. There is a chance because most people get their flu vaccines in the peak time for influenza infection that they could have already been exposed, but do not have symptoms yet or could be exposed in the two weeks after the vaccine. For every vaccine there is a window of time between when the vaccine was given and when your body produces peak antibodies, and for influenza it is around 2 weeks. This year’s flu vaccines contain either three or four strains of influenza depending on the form of the vaccine you receive. Each year the flu vaccines contain protection against strains of Influenza A and Influenza B and what strains are included are based on previous year’s strains and what is going on in other parts of the world.
While we recommend everyone be vaccinated for influenza, there are a few groups for whom this is especially important. Children under 5 years old and particularly those under 2 years old are most vulnerable, as are those over 65 years old. People with underlying long term conditions such as heart and lung conditions, or those with diabetes are more vulnerable at any age. The minimum age for vaccination is 6 months old, so we recommend caretakers of young babies be vaccinated to help protect them from infection. There are a few people for whom the flu vaccine is not a safe choice and that can include some people with an egg allergy. If you fall into that group, talk to your allergist to find out if the flu vaccine is for you.
No vaccine is 100 percent effective, so sometimes you can still get influenza even after you have been vaccinated, or maybe you are exposed before you had a chance to go get your vaccine. If you think you have influenza this is a time when going to see your healthcare provider earlier rather than later can be helpful. There is rapid testing available at most clinics for Influenza A and B and many can give results within 15 minutes. These tests are done by taking a swab inside the nose and are most helpful if done in the first three days of your illness. After this time the amount of virus that you shed through your nose goes down quickly, which is good for those around you because they are less likely to get sick from you, but is bad for confirming if influenza is what is making you feel so crummy.
Another reason to go in early in your illness is that the medications that can be prescribed for influenza are most effective if started in the first 48 hours of being sick. The antiviral medications are not needed for everyone and the young, old and chronically ill are likely to benefit the most from taking them. Pregnant women are another group that will usually get treated if positive for influenza. Your healthcare provider can decide if antiviral medications are going to be a helpful part of your recovery. Other measures such as fluids, rest and medication for pain or fevers can also be used as you get better from influenza.
It is recommended that you stay home from work or school/daycare until you are 24 hours fever free to help reduce the risk of spreading influenza to others. Some people who are exposed to influenza will benefit from medication before they have symptoms, and those include people who have abnormal immune systems, cannot be vaccinated, were vaccinated less than two weeks before exposure and those in long term care facilities.
If you have questions about influenza or vaccination, please call your healthcare provider or go to cdc.gov. Stay healthy this winter!
* Written by Dr. Sarah Jackson. Dr. Jackson is a pediatrician at Mercy Clinics Pediatrics Waukee. To schedule an appointment with Dr. Jackson or with another physician at Waukee Peds, please call (515) 643-7090.