University of Otago-linked research could prove a crucial "game-changer'' in the global battle against childhood pneumonia, which kills nearly a million young children each year.
Prof David Murdoch, an infectious disease specialist at Otago's Christchurch campus, said New Zealanders had played key roles in a global study, pinpointing the deadliest forms of viruses and bacteria.
The researchers had also identified one vaccine that could save the lives of hundreds of thousands of babies and young children.
"That will really push on the effort to get a vaccine for RSV treatment.
"That, in particular, is a game-changer,'' he said.
Many different bacteria and viruses contributed to the common pneumonia which caused the death of many babies and children in developing countries.
However, in the study, spanning seven countries, including Thailand, Bangladesh, South Africa and Kenya, the researchers found one virus, (RSV), which was present in more than a quarter of all cases.
Findings from the decade-long global Pneumonia Etiology Research for Child Health (PERCH) study are published in the latest edition of the prestigious Lancet journal.
Prof Murdoch led the establishment of laboratories in seven countries involved in the study.
The PERCH team - funded by the Bill and Melinda Gates Foundation - set up laboratories in the seven countries, in Asia and Africa.
They did a wide range of tests on children hospitalised with severe pneumonia to pinpoint the specific viruses and bacteria involved.
The researchers found a wide range of bacteria and viruses across the seven countries - some linked to worse outcomes for children.
Pneumonia kills more under-fives worldwide than any other disease. Almost 1 million children globally died from the disease in 2015.
Prof Murdoch said the PERCH study gave direction on where to put resources and scientific basis for vaccination programmes in countries with the greatest burden of childhood pneumonia.
"Before PERCH we were reliant on old data from the 1980s. The landscape has changed since then with the roll out of vaccines against some important causes of pneumonia, the AIDS epidemic, increased urbanisation, the development of antibiotic resistance, and availability of better diagnostic tests."
Prof Murdoch says by understanding the range of viruses and bacteria causing the disease in each country, the research gives individual nations, and global agencies such as the World Health Organisation, a clear battle plan to combat pneumonia.
The PERCH study found more than 7% of children with severe pneumonia involved in the study died within a month of hospitalisation.
In some countries, such as a Zambia, the death rate was much higher - with at least one in five children dying within a month of going into hospital.
Prof Murdoch is also a senior staff member at the Canterbury District Health Board's Canterbury Health Laboratories (CHL).
CHL staff played a major role in the study, and helped train and mentor scientists in the overseas laboratories.
The Christchurch staff also established consistent quality protocols and did some of the more specialised tests required.
Prof Murdoch says there are few diagnostic laboratories, such as CHL, that have sufficient breadth of expertise to provide the support required for such a large and complex study.
CHL has also been part of previous large pneumonia studies and this experience was crucial to the success of PERCH, he said.
A major focus would now be on the development of effective vaccines and treatments against the important causes of childhood pneumonia identified by the PERCH study, he said.