E. coli O157:H7 is a threat with young children not only because it can make them quite ill, but also because they can shed it in their feces for up to two weeks after their illness resolves, giving them plenty of opportunity to pass the disease on to others.
Older children don’t usually carry the organism without having the symptoms of the disease. Since it’s impossible to know which kids are still shedding the virus in their feces, E. coli can easily be spread around a day care center even when there isn’t anyone who seems ill.
While salmonella and campylobacter infections have declined in recent years thanks to the introduction of new food safety regulations for meat and poultry and improved agricultural practices for produce, the incidence of E. coli O157:H7 infections has not declined. The only known person-to-person transmission of E. coli occurs from child to child in day care centers.
If E. coli is to be controlled we have to make sure that everyone in day care centers washes his hands after using the toilet, and that caregivers wash the hands of kids who are too little to do it themselves. It should be unnecessary to add that adults must wash their hands after they change a child’s diaper and after they help a toddler use the toilet.
Maintaining hygiene in a place like a day care center is difficult. There are lots of messy kids in such places, and the more there are and the fewer adults to supervise them, the more opportunities there are to pass germs around. Antibiotics are not as effective as they once were. We need larger and larger doses of antibiotics to treat illnesses, and some germs have become partly or completely resistant to the drugs we have.
The reasons for this are complex, but one important reason is the overuse and misuse of antibiotics. Antibiotics kill germs, but germs evolve rapidly, and small changes in their genetic makeup can make them resistant to drugs. When an antibiotic is used, it kills the germs most susceptible, but leaves resistant strains to reproduce, increasing the percentage of resistant bacteria and limiting the effectiveness of the antibiotics.
This is particularly troublesome in day care centers, where resistant strains of many pathogenic microbes flourish. There are reports from all over the world, the United States, Portugal, Taiwan, Australia, Sweden, Canada, Israel, Bulgaria, Romania, and many other countries, of resistant strains of streptococcus and pneumococcus in day care centers.
Everywhere it is studied, it is clear that children in day care suffer more infections, and more antibiotic-resistant infections, than those in the same age group kept at home. But it is also true that these kids develop immunity to many illnesses sooner.