Where is streptococcus bacteria found

For these tests, a swab is used to take a sample from the throat. If these results indicate infection positive results , the diagnosis of strep throat is confirmed, and a throat culture, which takes longer to process, is not needed. However, results of rapid tests sometimes indicate no infection when infection is present called false-negative results. If results are negative in children and adolescents, culture is needed. A sample taken from the throat with a swab is sent to a laboratory so that group A streptococci, if present, can be grown cultured overnight.

In adults, negative results do not require confirmation by culture because the incidence of streptococcal infection and risk of rheumatic fever in adults is so low. If group A streptococci are identified, they may be tested to see which antibiotics are effective a process called susceptibility testing Testing of a Microorganism's Susceptibility and Sensitivity to Antimicrobial Drugs Infectious diseases are caused by microorganisms, such as bacteria, viruses, fungi, and parasites.

Doctors suspect an infection based on the person's symptoms, physical examination results, Close contacts of a person with a streptococcal infection should be checked for the bacteria if they have symptoms or have ever had complications due to streptococcal infection. Doctors cannot tell just by looking whether a sore throat is caused by a streptococcal infection or a virus. Cellulitis and impetigo can often be diagnosed based on symptoms, although culture of a sample taken from impetigo sores can often help doctors identify other microorganisms that may be the cause, such as Staphylococcus aureus.

To diagnose necrotizing fasciitis, doctors frequently use x-rays, computed tomography CT , or magnetic resonance imaging MRI and culture. Exploratory surgery is often required to confirm the diagnosis. Antibiotics shorten the duration of symptoms in young children but have only a modest effect on symptoms in adolescents and adults. Nevertheless, antibiotics are given to help prevent the spread of the infection to the middle ear, sinuses, and mastoid bone, as well as to prevent spread to other people.

Antibiotic therapy also helps prevent rheumatic fever, although it may not prevent kidney inflammation glomerulonephritis.

Usually, antibiotics do not need to be started immediately. Waiting 1 to 2 days for culture results before starting antibiotics does not increase the risk of rheumatic fever. An exception is when a family member has or has had rheumatic fever.

Then, every streptococcal infection in any family member should be treated as soon as possible. Usually, penicillin or amoxicillin is given by mouth for 10 days.

One injection of a long-lasting penicillin benzathine can be given instead. People who cannot take penicillin can be given erythromycin , clarithromycin , or clindamycin by mouth for 10 days or azithromycin for 5 days. The bacteria that cause strep throat have never been resistant to penicillin. Fever, headache, and sore throat can be treated with acetaminophen or nonsteroidal anti-inflammatory drugs NSAIDs , which reduce pain and fever.

However, children should not be given aspirin because it increases the risk of Reye syndrome Reye Syndrome Reye syndrome is a very rare but life-threatening disorder that causes inflammation and swelling of the brain and impairment and loss of function of the liver. The cause of Reye syndrome is Prompt treatment with antibiotics can prevent streptococcal infection from spreading rapidly and reaching the blood and internal organs.

Consequently, cellulitis is often treated without doing a culture to identify the bacteria that are causing it. In such cases, doctors use antibiotics that are effective against both streptococci and staphylococci such as dicloxacillin or cephalexin.

Serious streptococcal infections such as necrotizing fasciitis, endocarditis, and severe cellulitis require penicillin, given intravenously, sometimes with other antibiotics. People with necrotizing fasciitis are treated in an intensive care unit ICU Types of units People who need specific types of care may be put in special care units. Intensive care units ICUs are for people who are seriously ill. These people include those who have had a sudden, general In necrotizing fasciitis, dead, infected tissue must be surgically removed.

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Types of streptococci. Spread of streptococcal infection. Complications of streptococcal infections. Group A Streptococcus group A strep is a type of bacterium germ that can be found in the nose and throat and on the skin. These bacteria might be present and not cause any illness, or they can infect different parts of the body and cause disease that can range from mild to severe.

The most common infections caused by group A strep are strep throat and skin infections, such as impetigo. Serious disease can result when the bacteria invade internal parts of the body, such as the bloodstream, which is called invasive group A strep disease. In Virginia, about cases of invasive group A strep disease are reported each year.

Anyone can get a group A strep infection. Strep throat is particularly common in children. Few people who come in contact with the bacteria will develop invasive group A strep disease. Although healthy people can get invasive group A strep disease, people with chronic illnesses like cancer, diabetes, and chronic heart or lung disease, and those who use medications such as steroids have a higher risk.

People with skin lesions such as cuts, chickenpox, and surgical wounds , people aged 65 years or older, and adults with a history of alcohol abuse or injection drug use also have a higher risk for invasive group A strep disease.

Group A strep bacteria are spread by direct contact with body fluids, such as secretions from the nose and throat or wound drainage from an infected person. Casual contact as in work and school and household items like toys rarely play any role in spreading the bacteria.

The risk of spread of group A strep is greatest when an individual is ill; people who carry the bacteria but have no symptoms are much less contagious. The vast majority of GAS infections are relatively mild illnesses, such as strep throat and impetigo. Occasionally, however, these bacteria can cause much more severe and even life threatening diseases such as necrotizing fasciitis occasionally described as "the flesh-eating bacteria" and streptococcal toxic shock syndrome STSS.

In addition, people may carry group A streptococci in the throat or on the skin and have no symptoms of disease. These bacteria are spread by direct contact with nose and throat discharges of an infected individual or with infected skin lesions. The risk of spread is greatest when an individual is ill, such as when people have strep throat or an infected wound.

Individuals who carry the bacteria but have no symptoms are much less contagious. Treatment of an infected person with an appropriate antibiotic for 24 hours or longer eliminates contagiousness. However, it is important to complete the entire course of antibiotics as prescribed. Household items like plates, cups and toys do not play a major role in disease transmission. Invasive GAS disease is a severe and sometimes life-threatening infection in which the bacteria have invaded parts of the body, such as the blood, deep muscle and fat tissue or the lungs.

Approximately 20 percent of patients with necrotizing fasciitis and 60 percent with STSS die. About percent of patients with other forms of invasive group A streptococcal disease die.

Early signs and symptoms of necrotizing fasciitis include fever, severe pain and swelling, and redness at the wound site. Early signs and symptoms of STSS may include fever, dizziness, confusion, low blood pressure, rash and abdominal pain. Approximately 9,, cases of invasive GAS disease occur in the United States each year resulting in 1,, deaths.

In contrast, there are several million cases of strep throat and impetigo annually. Clusters of cases or outbreaks of invasive GAS have not been reported in any schools or communities in New York State. Invasive group A streptococcal infections occur when the bacteria gets past the defenses of the person who is infected.