No one knows how many newborns are dying each year due to antibiotic resistant infections, because of a lack of funding to research the issue fully, Professor Mike Sharland from St George's, University London said.
For every 1 p invested in research on infections in babies, HIV and malaria received £0.46 and £0.34, based on an overall measure of the disease burden.
But some neglected tropical diseases have strikingly high investments, such as African trypano somiasis, commonly known as sleeping sickness, which gets £9.06.
More money was need to research the impact of antibiotic resistance in babies, he said.
"It's a threat that gradually gets worse, but there is less interest in researching a more silent and slow concern, compared to the Ebola and Zika virus, as they are immediate threat to humans," he said.
"There has been a major efforts globally to get mothers to deliver in hospitals, which has been a great success, but there has not been the investment in neonatal units and research, where hospital acquired infections are a global problem."
Professor Sharland said babies are getting the same antibiotics that were used 50 years ago to treat septic infections.
"There are new antibiotics that are coming through that do treat resistant infections, but they are not proposing studies in babies for many years, yet there are a lot of multi resistant bugs out there," he said.
Future trials need to focus on improving the death outcomes in newborns by looking at the best choice of drug, dose and duration to fight highly resistant bugs as this information is completely unknown at the moment, Dr Sharland said.
"A joint approach from funders and research institutions is urgently needed to strengthen neonatal infection research, including specific funding to support research on the burden of antibiotic resistance in babies," he said.
"Developing research capacity worldwide is essential to drive forward measures to reduce deaths and disability from neonatal infection and to reduce gross inequities in health."
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