Antiseptic Curbs Blindness, UCLA Researchers Say : Medicine: Kenya study shows form of Betadine used on newborns prevents infections. It is safer and cheaper than widely used silver nitrate, research finds.

Applying a form of the common antiseptic Betadine to the eyes of newborn children could prevent as many as 10,000 cases of blindness and hundreds of thousands of severe eye infections each year worldwide, UCLA researchers report today.

Silver nitrate or antibiotics are commonly used in this country and Europe to prevent such infections, but the drugs are too expensive to be used in developing countries and can trigger inflammation. Most such countries thus use nothing, leading to widespread eye infections and blindness.

Drs. Sherwin Isenberg and Leonard Apt of UCLA’s Jules Stein Eye Institute report in the New England Journal of Medicine that trials on more than 3,000 newborns in Kenya show that povidone-iodine, the generic name for Betadine, is safer and more effective than silver nitrate and antibiotics in preventing eye infections, yet costs only pennies per application. Bacteria also do not seem to develop resistance to it, as they do to antibiotics.

Use of the antiseptic on newborns has begun at hospitals in Nairobi and other Kenyan cities as a result of their research, and the team is urging its adoption throughout Africa and the world.

“We’re quite excited about this,” Apt said. “This should be the drug of choice for prophylactic eyedrops in all newborns.”

“This is the kind of study that could change the way we practice medicine, not only in this country, but throughout the world,” said Dr. Bartly Mondino, director of the Jules Stein Institute, who was not involved in the research. “This is perhaps the way this problem (eye infections) will be dealt with in the future.”

The use of povidone-iodine “appears very promising, particularly in developing countries,” said Dr. Allen Foster of the Institute of Ophthalmology in London. Its adoption throughout the world, he said, could lead to substantial reductions in blindness caused by postnatal eye infections.

Eye infections after birth are called neonatal conjunctivitis. They usually are caused when the infant is exposed to bacteria or viruses in the mother’s vagina. The incidence rate varies widely, ranging from about 1.6% or less in the United States to 23% in Kenya, where nearly a third of women suffer venereal infections.

In the United States, about half of all neonatal infections result from chlamydia infections, whose incidence has grown sharply in recent years.

The application of silver nitrate drops to newborns’ eyes to prevent infections has been used since 1881 and is generally quite effective. A small percentage of children, however, develop severe redness and swelling, a condition called chemical conjunctivitis that is often mistaken for the bacterial disease but is not vision-threatening.

Isenberg and Apt began looking at povidone-iodine more than a decade ago when they were searching for a better way to sterilize eyes before eye surgery. Silver nitrate was used for that as well, but many cases of infection still resulted. They decided to apply a 5% solution of povidone-iodine--about half the concentration found in store-bought Betadine--to the eyes before surgery.

“We were shocked at the effectiveness,” Isenberg said. “It was much better than anything we had tried.”

It reduced the postoperative infection rate 40%, he said. The preparation is now used routinely at most U.S. medical centers for eye surgery.

The researchers turned to studies of newborns, using a more diluted solution, only 2.5%. They conducted a preliminary trial on 100 babies at Harbor-UCLA Medical Center. That study suggested that the new preparation was more effective than silver nitrate and much less likely to cause chemical conjunctivitis.

Working with Dr. Mark Wood of Presbyterian Church Hospital in Kikuyu, Kenya, the researchers tested povidone-iodine against silver nitrate and erythromycin on 3,000 infants born at the hospital between March, 1991, and August, 1993. Each infant received one of the three preparations in both eyes within 20 minutes after birth.

Compared to the normal rate of 23% of untreated infants developing infections, 17.5% of those treated with silver nitrate developed infections within the first month, compared to 15.2% of those treated with erythromycin and 13.1% of those treated with povidone-iodine. The relatively high incidence of infections in all three treated groups probably arose, Isenberg added, because many children picked up infections at home after they were released from the hospital.

There were only 104 cases of chemical conjunctivitis among the Betadine-treated infants, compared to 129 in the silver nitrate group and 148 in the erythromycin group.

But the biggest difference was cost, Apt said. A vial of silver nitrate that will treat a few infants costs $7, while the same amount of povidone-iodine costs 10 cents.