"An unprecedented challenge demands an unprecedented response, and it will take the work of the 7·5 billion people now alive to ensure that the health of a child born today is not defined by a changing climate", the authors said.
Meanwhile, nine of the top 10 years where conditions were most ripe for dengue fever transmission have occurred since 2000, the report said.
The Lancet notes that if we intervene now to keep warming down and find ways to adapt, the savings to the health system and economic productivity down the road will in many places more than pay for the costs of those interventions.
A child cholera patient lies on a bed as he receives medical care at a health centre in the village of Islim, Yemen.
"As a direct result of this failure" the report concludes that "Australia remains at significant risk of declines in health due to climate change, and that substantial and sustained national action is urgently required in order to prevent this". "That means that kid will experience a 4C world", Nick Watts, executive director of The Lancet Countdown, told AFP.
"Across the world, children are among the worst affected by climate change", said the annual report on climate change which incorporates the findings of 35 academic institutions and United Nations agencies from every continent.
Scientists predict that the rising temperature will reduce yields of staple crops such as rice, maize, and soybean, causing prices to rise and leaving children at risk of malnutrition, stunted growth, and developmental problems.
Researchers warn that young people will face more risks like this as the climate changes.
Researchers determined that, as they age into adolescence, the impact of air pollution will worsen for current infants and children if current trends continue.
In addition, the frequency and severity of extreme weather events has also increased in the last few years. Globally, 77% of countries experienced an increase in daily population exposure to wildfires.
The number of exposures is a metric devised using the number of heatwave days or wildfire days and the number of people vulnerable to them.
"Over the past two decades, the Government of India has launched many initiatives and programmes to address a variety of diseases and risk factors. But this report shows that the public health gains achieved over the past 50 years could soon be reversed by the changing climate", says Poornima Prabhakaran from the Public Health Foundation of India.
One of the major Australian concerns expressed by the report is the health effect of heatwaves, which according to Associate Professor Yuming Guo, can be linked with higher suicide rates. These people are not able to respond adequately also because the public health challenge is compounded by poor health health systems and infrastructure.
Since 2016, parts of northern and inland New South Wales, along with southern Queensland, have been in drought that the Bureau of Meteorology says is being driven, in part, by warmer sea-surface temperatures affecting rainfall patterns.
Climate change is already damaging the health of the world's children and is set to shape the wellbeing of an entire generation unless the world meets Paris Agreement targets to limit warming to well below 2˚C, according to the report published in The Lancet.
Delegates from different countries attending a plenary session at the COP24 UN Climate Change Conference in Katowice, Poland.
By the time he or she turns 71, the world will be 4 degrees-Celsius (deg-C) warmer than the pre-industrial levels of the mid-1700s.
In a briefing directed at European Union policymakers, researchers have warned that rising temperatures are increasing the range of disease-bearing mosquitos, while estimating that air pollution caused primarily by fossil fuel consumption costs European Union nations between €330-940bn a year.
Nothing short of a 7.4 per cent year-on-year cut in fossil Carbon dioxide emissions from 2019 to 2050 will limit global warming to the ambitious goal of 1.5 degrees Celsius, it says.