Influenza

As everyone knows by now, the 2003-2004 flu season is shaping up to be a bad one. The flu has started earlier than usual and seems to be particularly nasty strain.   There are a number of reasons this happens from time to time.

Influenza is a respiratory illness caused by a virus.   The influenza virus infects pigs and chickens as well as people, and the virus is able to change and mutate to evade the immune defenses mounted by its victims.   That is why a person can get flu many times, unlike other viral illness such as measles and chicken pox.   The virus actually changes the substances on the surface of the viral particle so that the host's immune system does not recognize and inactivate it.  

Every year a panel of physicians and scientists decides which strains are likely to be common during the following flu season so that they can be included in the coming season's flu vaccine.   This decision has to be made nearly a year ahead of the flu season.   Sometimes a new strain emerges after that decision is made.   This may have happened this year, making the current flu vaccine somewhat less protective against the strain of flu that seems to most common during this early flu season.

When there is a dramatic change in the circulating flu virus between seasons lots more people tend to get sick with the flu.   Over the years we build up some immunity to the flu viruses we have been exposed to.   A big change means that fewer people have antibodies and more people get sick with the flu.   Young children, older folks and people with underlying medical problems tend to get sicker with the flu and are more prone to serious complications.  

The symptoms of flu are primarily fever and dry cough, usually with headache and body aches.   Sometimes other symptoms can be prominent, such as nausea or sore throat.   The severity of the flu depends on many factors, including the age of the patient, partial immunity they may have from previous exposures, other health problems like asthma or diabetes that increase the risk of complications, and so on.

Influenza has a negative effect on the immune system, so infection with the flu virus makes the patient more prone to bacterial infections such as pneumonia, sinus and ear infections.   These are called secondary infections and are the cause of most serious illness and even deaths as a result of flu.  

There are several things we can do to prevent flu.   The flu vaccine can be effective even when given during the flu season, though it is most effective when given in October or November before the flu has started to circulate in earnest.   Wash hands frequently during flu season to prevent the accidental transmission of viruses picked up on environmental surfaces to the mucous membranes of the eyes, nose and mouth from the hands.   If you can, avoid public places where you may be exposed to other ill people.

If you do get symptoms of flu, there are medicines that can help you get better faster, though these medicines only help if started within 48 hours of getting sick.   These antivirals, such as Tamiflu, shorten the illness by a day or two and must be prescribed by a doctor (or Physician Assistant or Nurse Practitioner).   Fever and aches can be treated with acetaminophen (Tylenol) or Ibuprofen (Motrin IB, Aleve).   Nasal congestion can be treated with over the counter medications like pseudephedrine (Sudafed) and cough with over the counter medications containing dextromethorphan (Robitussin DM, Delsym).

Watch out for the combination medications that treat a number of symptoms.   Drugs like Theraflu and Dayquil can help you feel better, but since they have acetaminophen and Sudafed, they should not be taken with other similar medicines.   If you take both Theraflu and Dayquil, for instance, you can get double doses of both acetaminophen and pseudephedrine which can cause serious side effects.

At this time of year hospitals, doctor's offices and Emergency Rooms get very busy caring for patients with flu and flu complications.   At MedEx, even though we are busy, you can get seen more quickly, and early treatment makes a difference with the flu.   If your fever lasts longer than 5-7 days, if you start to get better and then get worse again, if you develop thick green nasal discharge or are coughing up green phlegm, or if you have any other symptoms that concern you, please see a doctor.