Everyone goes into child rearing with a medicine chest full of folk wisdom: Feed a cold, starve a fever. Don’t give your baby a bath when she has a cold. Teething can cause a high fever; aspirin is a good way to bring it down. Today pediatricians would quarrel with those bromides - and even with some of the advice they themselves may have dispensed a decade ago, for few areas of medicine have changed as drastically as pediatrics. Here is a look at some of the new thinking that affects the health of every child.

The immunization push: The most important thing parents can do is make sure their children are properly vaccinated. But getting the right shots, in the right sequence, at the right time isn’t always easy, because the immunization cookbook keeps changing. Currently, the American Academy of Pediatrics (AAP) recommends that, in the first 18 months of life, children receive 10 vaccines, some in multiple doses, some in combination with others. Many are familiar: measles, mumps, rubella, polio, diphtheria, tetanus and hepatitis. Among the newer vaccines is Haemophilus influenzae b, known as “Hib,” which immunizes against bacteria that can cause several dangerous ailments, including meningitis; it was approved for infants under i year of age only in 1990. And just last year, the Food and Drug Administration approved a new toxoid against per-tussis (whooping cough) that has fewer side effects than the previous one.

One of the more controversial immunizations is the two-year-old vaccine for chickenpox. Some parents argue that because the disease is a normal and relatively harmless affliction of childhood, their kids should be spared this particular needle. But the AAP recommends the vaccine for all children between 12 and 18 months who have not already had chickenpox. The disease is more severe if it occurs after puberty, often turning into pneumonia. And at any age a poxy child is trouble for parents. “It’s more of an economic issue,” says Dr. Harry R. Lubell, a pediatrician in Sleepy Hollow, N.Y. “With two parents working, they’re going to lose a week of work for each child who gets chickenpox.”

Overall, American children are better protected by vaccines than ever. According to the federal Centers for Disease Control and Prevention (CDC), 75 percent of children between 19 and 35 months are up to date on their shots, compared with only 55 percent five years ago. And new vaccines are on the way. “I fully expect we’ll have vaccines for all common ailments in 10 years’ time,” says Lubell.

The age of asthma: But for now, kids still get sick. The leading chronic illness among American children is asthma. It affects about 4.8 million youngsters under the age of 18, and the number of cases has risen nearly 80 percent in the last 15 years, calculates the American Lung Association. The reason isn’t entirely clear. The cause may be environmental–air pollution, tobacco smoke, allergens in poorly ventilated homes, even cockroach droppings-or it may be that more kids are in day care, where they are exposed to other kids’ germs.

Asthma restricts breathing by clogging the airways; an attack can be treated with inhalers that dilate the bronchial passages. Asthma cannot be prevented entirely, but its effects can be diminished in several ways. Cleaning up children’s surrounding s–rugs vacuumed, bedding laundered–and the air they breathe (no tobacco smoke) is an obvious step. As long as they manage the disease properly, parents don’t have to treat asthmatic children like babies all their lives. “People should realize that asthma is common, and children don’t have to live sedentary lives because of it,” says Dr. Richard Evans of Children’s Memorial Hospital in Chicago.

Fighting crib death: Sudden infant death syndrome (SIDS), the dreaded “crib death,” kills about 3,000 babies a year, 95 percent in the first six months of life. The cause of SIDS isn’t known. Some kids have a slightly higher risk than others, They include premature babies and those with breathing problems arising from the way their brains regulate respiration. Researchers also think some crib deaths may be caused by placing babies face down on blankets or other soft bedding.

Several methods have been suggested for reducing the risk of SIDS. The most promising is to lay babies on their sides or backs. The AAP began to recommend that five years ago, and between 1998 and 1995 the number of crib deaths dropped 30 percent. Researchers also recommend breast-feeding, which helps fight respiratory ailments and allergies. Parents also should keep their babies away from tobacco smoke, which can clog breathing passages.

Other precautions are more controversial. Electronic monitors can warn of changes in breathing and heart rate, but they also produce frequent false alarms. Some researchers suggest that mothers should sleep with their babies, arguing that the mother will be more alert to any crisis, while her presence alone may help to rouse a child who has stopped breathing. Other researchers oppose the practice, citing the danger of roiling over on the baby.

Heading off trouble: Doctors are more aware than ever of the need for preventive measures. That’s partly because of the move to cost-conscious managed care. But in addition to saving money, prevention produces healthier babies. Parents still have a lot to learn. Though most know good hygiene is essential, few wash hands–their own or their children’s–as often as they should. Many germs spread more readily by hand than through the air.

The best thing parents can do to ensure preventive care is to maintain a strong relationship with a pediatrician–which isn’t easy in underserved poor areas or when health-insurance or managed-care arrangements mandate a change of doctors. The AAP calls the ideal pediatric practice a"medical home," a 24-hour-a-day service to which parents can comfortably turn, by telephone if not in person, whenever they need help. “The closer the relationship parents have with a pediatrician, the more potential there is for children to stay healthy,” says the AAP’s Dr. Thomas Tonniges.

Early diagnosis is one benefit. “If hearing loss is detected in a child between the ages of 4 and 6 months, the outcome is significantly improved,” says Tonniges. “A dislocated hip can be identified in a newborn and treated conservatively with a sling. But wait until the child is walking, and he may need surgery.” Without a primary physician, parents of sick kids all too often end up in hospital emergency rooms, where they generally encounter long waits, high costs–and a doctor who has never seen their child before. With all the recent advances in medical science and those still to come, today’s toddlers have unequaled prospects for long-term health. But their parents have to know how to make the system work for them.

51% of all parents worry that their child will have a serious accident or illness; 35% worry about finding good health care for their kids.