What Is Serology for Brucellosis?
Serology is the science dealing with blood serum and especially
its immunological reactions and properties. Blood sent for serology means the
serum will be tested for antibodies, antigens, and other immune system
Antibodies are proteins made by the immune system. They help to
destroy the following that can invade your body:
If antigens get into the body, they can cause a number of
illnesses and diseases. One of these is brucellosis.
Antibodies are structured to target specific antigens. This is
why serology not only helps determine whether a person has a current infection
but also what type of agent is responsible. The serologic test for brucellosis
is often simply known as the Brucella
If antibodies for Brucella bacteria are found in
your blood, you may have had brucellosis or you may currently have it.
Symptoms of Brucellosis
Brucellosis can be either acute (short-term) or chronic
(long-term) infectious disease. The symptoms include:
- muscle pain
- joint pain
- profuse sweating
- back pain
- swollen glands
Causes of Brucellosis
A class of bacteria called Brucella cause brucellosis. There are several
strains of these bacteria that can lead to problems in humans. These are:
- Brucella melitensis
- Brucella abortus
- Brucella suis
- Brucella canis
The bacteria tend to be passed from animals to humans. Animals
that can carry and transmit the Brucella bacteria include:
- dogs (rarely)
Brucella is not transmitted to humans
through casual contact such as touching. There’s an extremely low risk of
getting brucellosis from eating the meat of an infected animal if it’s fully
Most cases of brucellosis are due to direct contact with the
bodily fluids of infected animals. These include urine and blood. It can also
be passed on by direct contact with the tissues, placentas, and aborted fetuses
of infected animals.
Eating unpasteurized dairy products made from the milk of
infected animals can also put you at risk.
Purpose of a Serologic Test for Brucellosis
The bacteria that cause brucellosis are not passed easily from
animals to humans. Also, many people don’t come into contact with animals that
normally carry Brucella. As a result, testing will likely be
ordered if you have the symptoms and you were in a situation where
infection could have occurred.
People at higher risk than the general population include farm
workers and veterinarians. Slaughterhouse workers and meat inspectors also have
a higher-than-average risk.
Procedure for a Serologic Test for Brucellosis
If your doctor suspects you have brucellosis, you’ll need to
provide a blood sample to be analyzed.
This isn’t a complicated procedure, and shouldn’t cause any
severe pain or discomfort. Your doctor will insert a needle into a vein and
collect a small amount of blood in a vial. It will then be analyzed in the lab.
The test usually used to analyze your blood is called a Brucella agglutination
Understanding the Results of Serology for Brucellosis
Antibodies are produced in response to the Brucella infection.
A person who wasn’t exposed to Brucella shouldn’t have any
antibodies for the bacteria in their blood.
An absence of Brucella antibodies is considered
a normal result. If you do have these antibodies, it means you are or were
likely infected with the bacteria.
False Positives and Other Concerns About Reliability
There are a few reasons why diagnosing an active Brucella infection
can be challenging.
- Some other types of bacteria can cause a false
positive, which means testing positive for the presence of Brucella when
it’s not present.
- Some immunizations can cause a test to be
positive when there’s no infection.
- A positive test doesn’t always mean you have a
current infection. It could mean you were exposed to Brucella at
some point in the past. It might also mean you have an immunity against this
type of bacteria.
- If you were recently exposed to the Brucella antigen,
there may be too few antibodies to be detected by the test.
More tests or follow-up testing may be needed to confirm or rule
How Is Brucellosis Treated?
As with the vast majority of bacterial infections, brucellosis
is treated with antibiotics. The duration of the treatment will depend on
factors such as whether there are any complications. It’s possible for people
who have been treated to relapse. The symptoms can also persist for a long
time, sometimes even years.
It’s important to keep in mind that brucellosis is very rare. In
fact, there are only 100 to 200 cases of it per year in the United
States. If your doctor does suspect you have brucellosis, following up with
testing and treatment is vital to increase your chances of a full recovery.