Is It Flu Or Is It Anthrax?

How do the symptoms of common illnesses like the flu and a cold differ from the inhalation form of anthrax? Dr. Emily Senay helps us sort it out.

With the exception of one case, all of the cases so far of inhalation anthrax have had a relationship with clear exposure, which so far has been through contact with a letter that came in the mail to a targeted area.

Many people who feel flu-like symptoms are going to be concerned about anthrax, but the chances are that if you are not in a clearly targeted group, which so far is the media, the post office, or a government office, your chances of getting anthrax are remote.

But in some of the cases of the people who died of inhalation anthrax, they went to the doctors and reported flu symptoms. How can doctors tell the difference between someone with the flu and someone with anthrax?

Dr. Senay explains that hindsight is 20-20. Most of the inhalation anthrax victims clearly had high risk factors for contracting it. Prior to the first case of inhalation with Bob Stevens in Florida, who died a month ago, there hadn't been an anthrax case in the United States in more than 20 years. So, doctors have a lot of catching up to do, but they have a better idea of what to look out for now and they are getting up to speed.

If people tell their doctors they are concerned about having anthrax, the first thing the doctors will probably do is evaluate their environmental risks of contracting it. The early signs of anthrax do mimic the flu, but the people who have had inhalation anthrax have appeared much sicker and profoundly more fatigued than someone normally is with the flu.

Anthrax Symptoms

Here is a list of the symptoms of inhaled anthrax that the CDC [Centers for Disease Control and Prevention] has recommended that doctors look for.

Fever with or without chills.
Sweats, often drenching.
Fatigue.
Dry cough.
Shortness of breath.
Headache and muscle pains.
Chest discomfort.
Nausea, vomiting, diarrhea, abdominal pain.
Sore throat.

Actually, flu season isn't here yet. It peaks from the end of December through March. Many people use the term "flu" as a general term for any respiratory illness when they have body aches, a fever, and a cough. According to the CDC, the average adult gets between one and three respiratory illnesses a year, and children may get from three to six respiratory illnesses a year. So these are very common. Most cases of flu-like illnesses are not the flu, nor would they be anthrax.

Flu Symptoms

Here are the common symptoms of the flu:

Fever.
Cough.
Sore throat.
Runny or stuffy nose.
Headache.
Fatigue.
Muscle aches.

Although anthrax is a bacterial disease and influenza is a virus, unfortunately, the early symptoms that both have in common are fever, headache, cough, and aches. But doctors have noticed that none of the people wh had inhalation anthrax complained about a runny or stuffy nose, upper respiratory problems, or wet, hacking coughs.

Anthrax patients also have had a high white cell counts, and none of them had low white cell counts. Also, nausea, vomiting, and diarrhea, which are included in the symptoms list for anthrax, are not usually symptoms of the flu.

Not everyone needs a flu shot. The people who should get a flu shot every year are people over 65 years old, people with weak immune systems, and those with heart or lung illnesses, because they are at the risk of suffering from it the most.

About 20,000 people died in the US from the flu last season, and 114,000 people were hospitalized. If you are not in one of the high-risk groups, you don't have to get a flu shot, but it is a good idea to get one. Getting a flu shot does not mean that you won't get the flu, but you will probably get a milder form if you do get the flu. It certainly will not protect you from anthrax. But if yodo not have the severe kinds of symptoms for anthrax, getting a flu shot may relieve your fears about mild flu symptoms being something more.

Remember that the people who succumbed to inhalation anthrax reportedly had severe nausea and vomiting, which is not a big symptom of the flu.

How to Tell Difference?

Is there a quick way for doctors to rule out the flu? Dr. Senay says, "There are different rapid flu tests that I think will get a lot of use this flu season. You can take one of them in your doctor's office and in less than 30 minutes find out if you have the flu. It takes 2 to 7 days to get results from a standard flu culture."

But, Dr. Senay warns, while these tests are good at detecting the flu, they fall short of completely ruling out the flu. In other words, if you test positive, you can be up to 99% sure that you have the flu. If you test negative, depending on the test, up to 25% of the cases identified as negative are actually influenza. Also, keep in mind that if you test negative for the flu, it doesn't mean that you have anthrax.

In addition to a rapid flu test, doctors may choose to do chest X-rays more often now for people with the flu, because that can also help distinguish anthrax from influenza.

This may be a difficult flu season. Doctors are learning about what to watch out for, and we all are. But we have to keep in mind what we know about the symptoms of anthrax in comparison to flu symptoms in perspective. And also that the chances of contracting anthrax are still very remote for the general population.

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