Who, What, Why: How can a baby survive in a storm drain?

Drain where the baby was found Image copyright Rex Features

A newborn baby is receiving treatment after surviving for up to five days in a drain in Sydney, Australia. How is that possible, asks Justin Parkinson.

The baby boy, who was found 2.5m (8ft) down a stormwater drain by the side of a road after passing cyclists heard him crying, is being treated for dehydration and malnutrition.

Dr Simon Newell, vice-president of UK's Royal College of Paediatrics and Child Health, describes the reports that he is alive after remaining there alone for up to five days as "absolutely amazing".

He says newborn babies are designed to survive a few days without much in the way of nutrients, as they adapt to the initial difficulties of breastfeeding. They have reserves of fluids and body sugars to keep them going during this period. This means babies do not need many extra fluids for the first four days or so of life in normal conditions.

But it is unlikely the boy could have survived as long as five days in abnormal conditions, such as a drain, without access to any water or nutrients, according to Newell. He suggests the information about when the baby was left in the drain could be inaccurate.

Sydney has been experiencing daytime high temperatures of up to about 40C during the past week and, crucially, overnight lows have not gone below about 18C. Dry conditions mean little or no water was likely to have flowed through the drain. The naturally stabilising effect that being underground has on temperature, and the protection from direct sun, may have provided good survival conditions.

"I doubt the child would have lasted this long in the UK," says Newell, "particularly at this time of year, when temperatures are so much lower."

If the baby was indeed underground for five days he was probably found in the nick of time, as bodily functions would normally be expected to break down before this stage.

His condition is described as a serious but stable and he is likely to be receiving intravenous fluids and possibly oxygen at Sydney's Westmead Children's Hospital.

The fact that he was crying loudly when discovered is a good sign, according to Newell. "I would be quietly optimistic that a healthy child can come out of this, without being damaged in some way," he says. "It takes a lot of effort for a baby to cry and it means there is a good chance. Babies are tougher than they're given credit for."

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