Is Strep Throat Contagious?

Is Strep Throat Contagious?

Strep throat is one of the most common causes of a sore throat, especially in kids five to fifteen years old. Estimates suggest that 15 to 40 percent of sore throats in this age group are caused by strep throat. Children will typically average one case of strep throat every four years. By comparison, just 5 to 10 percent of sore throats in adults are a result of strep throat.

Part of that discrepancy comes from strep throat’s contagiousness. Kids spend more time together in classrooms, playgrounds, and playdates. Read on to learn more about strep throat, how it can spread, and what you can do to potentially prevent it.

Strep Throat and Bacteria

Strep throat is a bacterial infection caused by a species of bacteria known as Streptococcus pyogenes, also known as group A Streptococcus (GAS). This is the more common bacteria and main cause of most cases of strep throat. Streptococcus pyogenes is also responsible for toxic shock syndrome, sinusitis, pneumonia, and certain skin infections, like impetigo and cellulitis.

A second species, simply known as group B Streptococcus, is rare and associated with more serious conditions, including blood infections and meningitis, which is an infection of membranes in the spinal cord and brain.

Group A Stretococcus has the unique ability to invade epithelial cells, which refer to cells lining organs and glands as well as the outer surface of your body. They tend to colonize the upper respiratory tract with most strains comprising respiratory and skin infections.

How Strep Throat Spreads

The Streptococcus bacteria is highly contagious, and as often as it happens to kids and teens, it can happen to just about anyone at any age. While there are documented cases of Streptococcus outbreaks originating in food and water, the occurrence would be rare in modern practice.

Streptococcus pyogenes can be spread via one-on-one contact. That includes kissing, hugging, or shaking someone’s hand. Once the bacteria is on your hands, it can reach your nose or your throat when you touch your face or eat food with your hands. The bacteria can also survive for some time on objects and surfaces, including doorknobs, telephones, and keyboards. You could contract the bacteria if you touched one of these surfaces and then touched your face.

However, the most common mode of transmission is respiratory droplets in the air. These are water droplets that come from a person’s mouth or nose after sneezing or coughing. The strep throat bacteria can easily enter your system should you accidentally breathe in these droplets.

In children, the bacteria is easily spread via these droplets as well as via nasal discharge. This combination is exacerbated by classroom environments that see large numbers of kids in close contact.

In skin infections, the bacteria can exist on the surface of your healthy skin for a week before you even see any lesions, sores, or other symptoms. Streptococci bacteria can also be harbored on fingernails, though these strains of bacteria are more often associated with skin infections like impetigo.

How Long Is Strep Contagious?

After being diagnosed with strep throat, you should stop being contagious within the first 24 hours of taking antibiotics. With antibiotics, you should show improvement in one or two days.

If you do take antibiotics for strep throat and don’t have a fever the night before going to school or work, you should be safe to venture into the public as you won’t be contagious. However, if you do have a fever the night prior, you will still be contagious and should plan to spend the next day recuperating at home.

Without antibiotics, strep throat should generally go away on its own within a week. However, you may still be contagious in the two to five days before you even begin exhibiting symptoms. This is known as the incubation period.

Furthermore, even after you feel better, the Streptococcus bacteria may still be in your system for the next few days, allowing you to spread it to others. Individuals who don’t use antibiotics may be contagious for a total of two to three weeks.

Knowing When You Have Strep Throat

The first step in knowing whether or not you have strep throat is to identify your symptoms. The main symptom of strep throat is a sore, itchy throat that comes on suddenly and quickly. This may be accompanied by:

  • A fever of 101 degree Fahrenheit or higher
  • Red, swollen tonsils
  • White patches or deposits on the tonsils
  • Headaches
  • Coughing
  • General feelings of illness
  • Enlarged, swollen lymph nodes along the sides of your neck
  • Purple and red spots on the roof of your mouth

Other symptoms, like a runny nose, red eyes, or diarrhea, may point to a viral infection instead of a bacterial infection.

Potential Complications from Strep Throat

While your body generally has the strength and immunities to fight strep throat on its own, it may still need help from antibiotics. Without antibiotics, you significantly increase the risk of strep throat progressing to become one of several more serious complications. Some of the most common complications include:

  • Acute rheumatic fever: This occurs when antibodies fighting the Streptococcus bacteria accidentally begin attacking the cells in your skin, joints, and heart. Ongoing damage to your heart’s muscles and valves can lead to congestive heart failure. This condition is rare thanks to the growth of antibiotics, but it’s still possible. Acute rheumatic fever generally occurs two to four weeks after strep throat’s onset.
  • Scarlet fever: This disease combines the sore throat and fever with a rough red rash that feels like sandpaper (giving scarlet fever its name). It generally only occurs in younger children under the age of 18.
  • Toxic shock syndrome: Group A Streptococcus may release gases and toxins that accumulate, leading to toxic shock syndrome. This condition is potentially life-threatening and is characterized by fever, rash, and low blood pressure. This can possibly progress the failure of multiple organs.
  • Post-streptococcal glomerulonephritis: Glomerulonephritis is a type of kidney disease characterized by damage to the part of your kidneys involved with filtering fluids and waste out of your blood. It is more common in children age two to 12 years old.
  • Sinusitis: Sinusitis, also known as a sinus infection, occurs when your sinuses become blocked preventing proper drainage of mucus. This allows for the growth and proliferation of bacteria, leading to an infection. The symptoms of sinusitis include congestion, coughing, postnasal drip, headaches, and nasal discharge.

Strep throat may also lead to the formation of abscesses on the tonsils. An abscess is essentially a bubble of tissue and pus. While it’s not necessarily harmful on its own, it can be painful and cause swelling. In more severe cases, abscesses can block the throat, making it difficult to swallow, speak, or even breathe.

Diagnosing Your Strep Throat

The main problem with strep throat is that many of its primary symptoms tend to overlap with other common illnesses, like the common cold and sinusitis. Administering antibiotics if it’s not strep throat may not only put a toll on your body, but also lead to the development of bacteria that may actually be resistant to antibiotics. This causes problems for you and becomes a larger public health concern. The best way to determine if you actually have strep throat is to consult a physician for a professional diagnosis.

The most common diagnostic test for strep throat is known as the rapid antigen test. During this test, your doctor will take a swab of your throat and analyze the swab for presence of any antigens. You can get fairly accurate results within minutes that show if the infection is caused by Streptococcus, a virus, or other invading organism.

If the results from the rapid antigen test come out as negative but your doctor still suspects that you may have strep throat, he may proceed with other tests, usually a throat culture. In this test, your doctor will swab your tonsils and the back of your throat. He’ll then rub the swab over some plates and let the plates incubate. If you do have strep throat, the bacteria will grow on the plates. This process can take up to two days, but it can be much more conclusive.

Treating Strep Throat

The best way to prevent the spread of the strep bacteria is to get treatment and get it early. Treatments for strep throat involve antibiotics, most commonly penicillin and amoxicillin. Getting treated early not only reduces the severity and duration of the infection, but also decreases the risk of you spreading the disease to those around you.

Taking antibiotics within 48 hours of the disease’s onset shows significant results. You should feel better within one or two days. Children can generally return to school about 24 hours after treatment. However, remember to take the full course of the medication to fully eliminate the infection. Stopping your antibiotics midway or too early can cause a relapse or lead to serious complications.

Aside from antibiotics, your doctor may prescribe medicine that can help to manage symptoms. This can include over-the-counter pain relievers, like acetaminophen and ibuprofen, that can reduce the severity of your fever while alleviating headaches and throat soreness.

Preventing the Spread of Strep Throat

Aside from treatment, the best thing you can do to prevent giving strep throat to others is to stay at home and rest until you feel better. Because of how communicable Streptococcus is, simply opening doors and speaking to others is enough to potentially spread the bacteria to coworkers, peers, friends, and family.

If you must go outside or suspect you’ll still be contagious while around others, some tips to keep in mind:

  • Wash your hands frequently and thoroughly using warm water and soap. As a general rule of thumb, you should be scrubbing for at least the length of the alphabet song. If you can’t reach a sink, keep some hand sanitizer on your person and use it frequently.
  • Cover your mouth whenever you cough or sneeze using a tissue or napkin. Cough or sneeze into your sleeve or your elbow if you don’t have anything else handy. If possible, consider wearing a flu mask. This may make it hard for others to understand you, but it can significantly prevent the amount of bacteria that you spread. Avoid covering your mouth with your hands. If you do, clean your hands immediately with soap and warm water.
  • Do not share any personal objects. That includes eating utensils and drink cups.

When you are feeling on the mend, consider disinfecting items in your home to prevent spreading the bacteria to potential guests. Switch out your toothbrush once you have fully healed as well.

If you have several kids in your household, expect all of them to get strep throat. Research suggests that there’s a 50 percent chance of a child sharing strep throat with their siblings.

If you suspect you might have strep throat, make sure you see your doctor or visit an urgent care center. You’ll make yourself feel better and prevent the spread of the disease.

Doctor on phone
Alexa Englehart

Alexa Englehart

Alexa currently lives in sunny San Diego, California. When not writing, she enjoys running, hiking, swimming, horseback riding, and reading.

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