Two brands of eyedrops were pulled from shelves in January and February after they were linked to a drug-resistant bacteria strain that has caused at least three deaths and eight cases of people losing their vision. Weeks later, two other types of eyedrops were recalled because they posed a different kind of contamination risk.

This flurry of recalls may have you second-guessing use of eyedrops, but there are significant differences among the recalls and steps you can take to stay safe.

"I would encourage all people out there who take eyedrops to continue using them, of course making sure that they're not using any of these that are recalled," said Dr. Christopher Starr, a clinical spokesperson for the American Academy of Ophthalmology.

Here's what to know about these recalls.

What eyedrops are recalled?

In January, the CDC and the Food and Drug Administration warned people to stop using EzriCare Artificial Tears and Delsam Pharma's Artificial Tears after the eyedrops were linked to a drug-resistant strain of the bacteria Pseudomonas aeruginosa.

Global Pharma Healthcare in India, which makes EzriCare and Delsam Pharma's eyedrops, recalled both products in February.

Last month, a Florida woman sued Global Pharma, claiming that an infection caused by the eyedrops was so severe that doctors had to surgically remove one of her eyes.

The FDA has also warned people to stop using an eye ointment manufactured by Global Pharma because of possible contamination.

The two other eyedrop recalls were not linked to the bacteria outbreak.

On March 1, Apotex recalled prescription eyedrops used to reduce eye pressure in people with glaucoma or ocular hypertension. The company recalled six lots of Brimonidine Tartrate Ophthalmic Solution 0.15% because at least four bottle caps developed cracks, which could affect the product's sterility.

On March 3, Pharmedica recalled two lots of Purely Soothing 15% MSM Drops because they were not sterile. These drops are used to treat eye irritation and swelling.

The CDC said that as of last week, the drug-resistant bacteria strain linked to the recalled EzriCare and Delsam eyedrops had been found in 68 people in 16 states.

To find out if you have eyedrops that were included in the recall, go to fda.gov/safety/recalls.

See a doctor for symptoms

People who have used these artificial tears and who have symptoms of an eye infection should see a doctor immediately, the CDC said. The symptoms can include yellow, green or clear discharge from the eye, redness of the eye or eyelid, increased sensitivity to lights and eye pain or discomfort.

Eyedrops are generally safe

Barbara Tylka, an optometrist at the Mayo Clinic in Rochester, said that in general, eyedrops are safe to use and that many people need them to treat conditions such as dryness or irritation. About 117 million Americans used eyedrops and eyewash in 2020, according to Statista, a market research firm.

To use eyedrops safely, Tylka said people should use their own bottle and make sure it has not expired. People who have had eyedrops prescribed to them for a procedure such as cataract surgery should stop using those products once the healing process is over, she said.

To safely apply eyedrops, she said, people should use their nondominant hand to "gently tug on the lower eyelid, look up slightly," and then, with the dominant hand, put "that little drop in that lower cul-de-sac in the eyelid area."

Starr, an associate professor of ophthalmology at Weill Cornell Medicine, said patients should not press the bottle tip into the inner corner of the eye, which can contaminate the drops and scratch the surface of the eye. He said that when he accidentally hits his eyelid or eyelashes with the bottle tip, he considers the bottle contaminated and either resterilizes it or replaces it.

Starr and Tylka both emphasized that although the recalls were worrying, eyedrops are generally safe.