Strep throat

Strep throat is a contagious bacterial infection that causes pain and swelling in the throat. Strep throat is easily treated with antibiotics. If not treated properly, however, strep throat can lead to serious medical conditions, including rheumatic fever and kidney disease.


Causes/associated factors
Strep throat is caused by a bacterium called group A streptococcus. The infection is most common during late winter and early spring, particularly among people who live in close quarters and school-age children.

Transmission
Strep throat typically spreads through person-to-person contact or by inhaling infected respiratory droplets in the air. Carriers (people who harbor the streptococcus organism in their throat or nasal cavities) can transmit the infection to others even when they don't have active symptoms of an infection themselves. Rarely, the infection spreads through contaminated food, especially eggs, milk and milk products.
The incubation period (time from exposure until symptoms appear, if they appear at all) is two to four days. You're no longer contagious 24 hours after you start antibiotic treatment. Without treatment, you may be contagious for up to 10 to 21 days.


Signs/symptoms
Sometimes, strep throat doesn't have symptoms. When symptoms develop, they may include:
a sudden red, sore throat
a sudden fever
chills
painful swallowing
white patches in the throat or tonsils
swollen, tender glands in the neck
headache
abdominal pain
nausea
vomiting
a general feeling of discomfort
fatigue
Coughs and runny noses aren't typical symptoms of strep throat. However, strep throat can develop during illnesses that often include a cough and runny nose, such as the flu.


Diagnosis
The doctor will ask questions about your medical history and do a physical exam. Based on your symptoms, you may need a throat culture or rapid strep test, which is done by swabbing the back of your throat for a sample of tissue secretions. Rapid strep test results are available in a few minutes. Be aware that false negative results are possible, especially if you ate or drank shortly before the test. If the test is negative but your symptoms indicate an infection, the doctor may recommend a backup strep culture. With this test, results may not be available for up to three days.
Other infections, such as mononucleosis, can mimic strep throat or appear at the same time. Based on your symptoms, you may need additional tests.


Treatment
Although strep throat may clear up on its own, it's easily treated with antibiotics such as penicillin or erythromycin. Antibiotic treatment shortens the length of the illness and reduces the risk of complications or subsequent development of acute (sudden) rheumatic fever. It also reduces the spread of strep throat to others with whom you have close contact, such as family members and schoolmates.
If your doctor prescribes antibiotics, remember to finish the entire prescription -- even if your symptoms clear up within a few days. To ease your throat pain in the meantime, consider the following treatment measures.

Suck on throat lozenges or hard candy. (Note: This isn't recommended for children age 4 or younger due to the risk of choking. Older children should only suck on lozenges or hard candy with adult supervision.)
Gargle with warm salt water three to four times a day. (Dissolve a half teaspoon of salt in an 8-ounce glass of water.)
Use a cool mist humidifier or hot steam vaporizer. Remember to clean the humidifier regularly according to the product instructions. A steamy shower may help as well.
Drink plenty of fluids, especially if you have a fever. Warm fluids are especially soothing for some people, while others prefer cold drinks.
Eat a soft foods, such as soup, pudding or ice cream.
Your doctor may also recommend an over-the-counter pain reliever.


Complications
Complications of strep throat may include:
tonsillar abscess (collection of pus in the tonsil) and prolonged enlargement of one or both of the tonsils
ear infections
sinusitis (inflammation of a sinus passage or cavity)
rheumatic fever (a condition that can cause inflammation of the heart, which may lead to chronic heart disease)
glomerulonephritis (inflammation of the kidney)
bacteremia (blood-borne infection)
localized head and neck infections
rarely, streptococcal toxic shock syndrome (a serious bacterial infection that causes sudden fever, vomiting, watery diarrhea and muscle pain)
Scarlet fever is another potential complication of strep throat. This condition is caused by strep bacteria, usually in association with a throat infection. Scarlet fever is characterized by a rash that appears primarily on the chest and abdomen. The affected skin may look as if it's been sunburned and feel rough to the touch. You may also notice increased redness in folds of skin, such as the groin area or the "bend" in front of your elbow or your armpits. The tongue often has a whitish to yellow coating when the rash first appears, but later becomes bright red. Your face or neck may be flushed, but the area around your mouth may appear pale. A fever, sore throat and other symptoms usually precede the rash by 18 to 24 hours. Like strep throat, scarlet fever is treated with antibiotics.

Complications can be especially serious, even life-threatening, for elderly adults, newborns, and people who are debilitated or have weak immune systems.


Pregnancy-specific information
If you think you may be pregnant and a doctor prescribes medication for strep throat, be sure to mention the possibility of pregnancy. If you know you're pregnant and suspect strep throat, consult your doctor right away to prevent potential complications. As a general rule, avoid contact with people who have active infections of any type while you're pregnant.

Senior-specific information
Although strep infections are often less common among older adults, they can develop when the immune system becomes less effective. If you have a chronic health condition, seek prompt medical treatment if you develop symptoms of strep throat. Remind your doctor of any allergies you may have and other medications you take. To strengthen your immune system, eat healthfully, complete all recommended immunizations, and lead a healthy lifestyle.

Prevention
To prevent strep throat, avoid crowded living conditions and contact with people who have untreated strep throat. Wash your hands often, especially before eating. Avoid sharing beverages or food with others, especially during later winter and early spring when strep is more prevalent.