The Blue Baby Syndromes
Did environment or infection cause a blood disorder in newborns?
Don’t Drink the Water
In the condition first described by Comly (now known as well-water methemoglobinemia), affected infants appeared healthy at birth and remained so through discharge. The cyanosis arose only after days, weeks or months in the home environment. What made Comly’s paper so noteworthy was the full explanation offered for the etiology of the disease—one that has been largely undisputed for 60 years.
He recognized that “the only significant change in the infant’s environment from hospital to farm home was in the water that was used to prepare the formula.” But what was the nature of the difference between hospital and home water? After the third episode of admission and treatment with methylene blue for one child, her father demanded to know exactly what “poison” in his well was responsible. Analyses of the water showed high levels of nitrate.
Inquiries to other physicians in the area about unpublished, similar cases turned up 17 more, with one fatality, suggesting that the condition was more common than suspected. As the number of physicians who reported seeing unexplained cyanosis in infants who had been fed powdered formula prepared with well water grew, measurements of the nitrate content of Iowa wells showed that more than half of the 91 wells initially sampled contained nitrate nitrogen in excess of 10 parts per million, and 20 contained more than 65 parts per million.
Those wells that tested high for nitrates were clearly undesirable from a public health standpoint. Most of them were old, shallow and dug rather than drilled, and they often had inadequate casings. Many were poorly covered so that surface runoff containing nitrate fertilizers or animal excreta rich in nitrates could enter freely. They were often found near barnyards, feedlots or pit privies, and some were contaminated with coliform bacteria. Although the wells served as the drinking water source for the entire family, only formula-fed infants were affected, and most were less than three months of age.
Subsequent independent surveys in midwestern states confirmed the initial results in Iowa. The most complete survey of all 48 states, plus what were then the territories of Alaska and Hawaii, was compiled in 1951 and identified 278 cases with 39 deaths. No cases were found in which wells contained 10 parts per million nitrate nitrogen or less, and only 2.3 percent of the cases involved wells with between 10 and 20 parts per million. Above 20 parts per million, the severity of the symptoms seemed to parallel the amount of nitrate present. Breastfed infants were never involved; neither were families who used municipal water supplies. No reports of cases prior to World War II were found. However, physician reporting was not mandatory for the condition, and the true number may have been much higher.
But by the time that report was published, the worst seemed to have passed, and the number of cases fell off steadily through the early 1950s. Today the disease has all but disappeared, with reports appearing only sporadically in the literature. Only two cases have been reported since the mid-1960s and none since 2000. Within 10 years the epidemic had waned as suddenly as it had appeared, without any preventive action having knowingly been taken. Whether it was because of public awareness, a massive improvement in rural drinking water quality, a trend toward breastfeeding or other factors may never be known.
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