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Conjunctivitis

life science Maturity 11-13

Your eye can look very pink.

Bloodshot eye.jpg
Bloodshot eye.jpg
It might feel itchy or scratchy. This can happen from germs. It can also happen from dust. It can even happen from things like pet hair. Washing your hands helps you stay well. Does your eye ever feel itchy?

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Your eyes can look very pink or red.

Bloodshot eye.jpg
Bloodshot eye.jpg
This can happen when the clear layer on your eye gets sore. It might feel itchy or scratchy. Your eyes may also make many tears.

Sometimes germs cause this. Germs can spread from person to person. You can help by washing your hands.

Conjunctivitis disease.jpg
Conjunctivitis disease.jpg

Other things can cause it too. Dust or pet hair can make eyes itchy. This is often from an allergy.

Some people find their eyes stuck shut in the morning.

Swollen eye with conjunctivitis.jpg
Swollen eye with conjunctivitis.jpg
This can happen if the eye is sticky. Most cases get better in a week or two. It is good to know how to keep your eyes healthy.

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Your eyes can turn pink or red. This is called conjunctivitis.

Bloodshot eye.jpg
Bloodshot eye.jpg
This happens when the conjunctiva gets sore. The conjunctiva is a thin, clear layer. It covers the white part of your eye. It also covers the inside of your eyelids.

Many things can cause this. Viruses are a common cause for adults.

Conjunctivitis disease.jpg
Conjunctivitis disease.jpg
Viruses can also cause a common cold. Bacteria are a common cause for children.
Swollen eye with conjunctivitis.jpg
Swollen eye with conjunctivitis.jpg
These germs can spread from person to person. You can help stop the spread by washing your hands.

Allergies can also cause red eyes. This happens when your body reacts to things like pollen or pet hair. These reactions make the eye itchy and watery.

Allergicconjunctivitis.jpg
Allergicconjunctivitis.jpg

Most cases get better in one or two weeks. Some people find their eyes are stuck shut in the morning. This is because the eye becomes sticky. If you have a lot of pain or cannot see well, you should see a doctor. In the United States, three to six million people get this each year.

177 words

You might notice your eyes turning pink or red sometimes. This is called conjunctivitis, but many people call it pink eye.

Bloodshot eye.jpg
Bloodshot eye.jpg
It happens when the conjunctiva becomes inflamed. The conjunctiva is a thin and clear layer. It covers the white part of your eye. It also covers the inner part of your eyelids. This swelling makes the eye look red. You might feel itching, burning, or a scratchy feeling. Some people find their eyes are stuck shut in the morning. This happens because the eye produces extra tears or sticky discharge.
Conjunctivitis disease.jpg
Conjunctivitis disease.jpg

There are many different ways this happens. Viruses are a very common cause for adults.

Swollen eye with conjunctivitis.jpg
Swollen eye with conjunctivitis.jpg
In fact, viruses cause about 80% of cases in adults. These viruses often come with a common cold or a sore throat. For children, bacteria are a more common cause. Bacteria cause about 70% of cases in kids. These germs can spread easily from person to person. They can also move through contaminated objects or water. Touching your eyes with dirty hands is another way germs spread.
Procedure of conjunctival swabs.jpg
Procedure of conjunctival swabs.jpg

Allergies are another big reason for red eyes.

Allergicconjunctivitis.jpg
Allergicconjunctivitis.jpg
This happens when your body reacts to things like pollen or animal hair. It can also be caused by dust mites, perfumes, or smoke. When this happens, your body releases a substance called histamine. This causes the small blood vessels to widen. This makes the eye look red and feel very itchy. Allergic cases affect between 15% and 40% of all people. This is a very common way to get eye irritation.

Doctors have many ways to find the cause. They look for signs like redness or swelling. Sometimes they use a tool called a slit lamp. This is a special microscope that helps them see better. They might also look at the inner eyelids. If they think bacteria are the cause, they might take a sample. They use a swab to collect some of the eye discharge. This sample can be sent to a lab for a culture. This helps them know exactly which germ is making the person sick.

Most people feel better in one or two weeks. In the United States, three to six million people get this each year. Treatment depends on what caused the problem. Most viral cases do not have a specific treatment. Bacterial cases might need antibiotics to get better faster. For allergies, doctors might use antihistamine eye drops.

Chlamydial-conjunctivitis.jpg
Chlamydial-conjunctivitis.jpg
If you have bad pain or cannot see well, you must see a doctor right away. This is important to make sure it is not something more serious.

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Conjunctivitis is the medical term for inflammation of the conjunctiva. The conjunctiva is a thin, clear layer of tissue. It covers the white surface of the eye, known as the sclera. It also lines the inner surface of the eyelids. When this tissue becomes inflamed, the eye appears pink or reddish.

Bloodshot eye.jpg
Bloodshot eye.jpg
This condition can affect one eye or both eyes. People often experience symptoms like burning, itching, or a scratchy sensation. Some individuals may also notice increased tearing or find their eyelids stuck shut in the morning due to discharge.

There are several distinct mechanisms that cause this inflammation. In viral conjunctivitis, viruses infect the tissue. This often occurs alongside other respiratory issues, such as a common cold or a sore throat.

Conjunctivitis disease.jpg
Conjunctivitis disease.jpg
In bacterial conjunctivitis, bacteria like Staphylococcus or Streptococcus cause the irritation. This typically results in a rapid onset of redness and a sticky, opaque discharge. Allergic conjunctivitis is an immune response. It happens when the body reacts to allergens like pollen, animal hair, or dust mites. This reaction causes mast cells to release histamine. The release of histamine leads to vasodilation, which is the widening of small blood vessels. This process causes the characteristic redness and swelling.
Allergicconjunctivitis.jpg
Allergicconjunctivitis.jpg

Doctors classify conjunctivitis based on its cause or the area it involves. The causes include viruses, bacteria, allergies, chemicals, or autoimmune responses. It can also be classified by how much of the eye is affected. For example, blepharoconjunctivitis involves both the conjunctiva and the eyelids. Keratoconjunctivitis occurs when the cornea, the clear front part of the eye, is also inflamed. If both the eyelids and the cornea are involved, it is called blepharokeratoconjunctivitis.

Membranous conjunctivitis.jpg
Membranous conjunctivitis.jpg
Some bacterial infections can even cause the formation of membranes. These are layers of inflammatory cells and fluids that adhere to the conjunctiva.

Different groups of people experience different types of conjunctivitis. In adults, viruses are the most frequent infectious cause, accounting for approximately 80% of cases. Adenoviruses are responsible for 65% to 90% of these viral instances. However, the pattern changes for children. In children, bacteria are the predominant cause, responsible for about 70% of cases. There is also a specific type called neonatal conjunctivitis. This affects newborns and is caused by different bacteria than common adult cases.

Chlamydial-conjunctivitis.jpg
Chlamydial-conjunctivitis.jpg

Diagnosing the exact cause is important for choosing the right treatment. Doctors often rely on observing signs and symptoms. They may use a slit lamp, which is a specialized microscope, to improve diagnostic accuracy. They typically examine the palpebral conjunctiva, which covers the inner eyelids, more closely than the bulbal conjunctiva. If a bacterial infection is suspected, a doctor might use a swab to collect a sample of the discharge.

Procedure of conjunctival swabs.jpg
Procedure of conjunctival swabs.jpg
This sample can be sent for a culture to identify the specific germ. For allergies, a patch test might be used to find the specific trigger.

Treatment strategies vary depending on the underlying cause. Most viral cases have no specific treatment and must resolve on their own. Bacterial infections can often be treated with antibiotics to shorten the illness. However, certain infections, such as those caused by gonorrhea or chlamydia, require specific medical attention. Allergic conjunctivitis is often managed with antihistamines or mast cell inhibitor eye drops. Chemical conjunctivitis, caused by acidic or alkaline substances, requires flushing the eye until the pH reaches a safe range of 6 to 8.

Conjunctivitis is a significant health issue in the United States. Between three and six million people suffer from acute conjunctivitis every year. Most cases typically resolve within one to two weeks. While most cases are not dangerous, some symptoms require urgent care. If a person experiences sudden visual loss, significant pain, or extreme sensitivity to light, they need an ophthalmologist. These signs might indicate more serious conditions like glaucoma, uveitis, or keratitis. Understanding the cause helps ensure the eyes heal properly and safely.

646 words
🖼️ Images & Media (7)
File:Bloodshot eye.jpg
Bloodshot eye.jpg
File:Conjunctivitis disease.jpg
Conjunctivitis disease.jpg
File:Allergicconjunctivitis.jpg
Allergicconjunctivitis.jpg
File:Swollen eye with conjunctivitis.jpg
Swollen eye with conjunctivitis.jpg
File:Membranous conjunctivitis.jpg
Membranous conjunctivitis.jpg
File:Chlamydial-conjunctivitis.jpg
Chlamydial-conjunctivitis.jpg
File:Procedure of conjunctival swabs.jpg
Procedure of conjunctival swabs.jpg
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