Asthma is one of the biggest afflictions that humans have had to face with urbanisation and industrialisation. At the turn of the 20th century it was relatively unheard of. But now it is an epidemic.
The World Health Organisation said 300-million people have asthma around the world. “Ongoing temperature increases are expected to increase this burden,” it said.
Several research papers in the journal Nature have linked temperature increases to greater amounts of pollen and mould. These are some of the primary triggers of asthma. This is because asthma is triggered by an allergic reaction. When something such as pollen is inhaled, the person’s airwaves constrict. This makes breathing hard and an inhaler is required to ease the pressure.
One study in the journal stated that “considerable increases in both prevalence of asthma and its severity have occurred globally over recent decades". Many local environmental factors are to blame, but the biggest change has been as a result of increasing temperatures, it said.
In the worst cases the person can die. The last statistics for asthma in South Africa, from 2010, said over 10 000 people die on average every year as a result. Research on this has however said the number is conservative, as people in townships and rural areas who have asthma attacks or die probably never make it to a hospital.
Professor Robin Green, a paediatric pulmonologist at the paediatrics and child health department at the University of Pretoria, said there was no data for what effect climate change would have on asthma locally. But he had done some basic research on this, which said climate change would create more pollen and fungal allergens.
“Changes in the climate are expected to alter the presentation, seasonality and epidemiology of respiratory diseases in the future,” the research paper said. This would probably make asthma a bigger problem for more parts of the population, it said.
Other asthma and pulmonology exeperts agreed with Green, saying no serious work had been done on future impacts of climate change on asthmatics.
Asthma is already a big problem in the country. The Global Initiative for Asthma lists South Africa as having the fourth-highest asthma death rate in the world among five- to 35-year-olds. One in 10 local people suffer from a form of asthma, it said.
In America, the Environment Protection Agency has done thorough research into asthma and climate change. It concluded that more carbon dioxide in the atmosphere and increased rainfall had led to increased levels of pollination. This was driving the constant growth of people suffering from asthma, it said.
'Biggest health challenges'
The allergy season in the United States was now 30 days longer than half a century ago. This was because temperatures have steadily increased since then, it said.
The National Institute of Environmental Health Sciences said: "In the coming century, asthma and other allergic respiratory problems will become some of the biggest health challenges we face."
There is no cure for asthma, and people living with it can only control their sysptoms. The drugs are, however, listed as essential so should be provided for free at all government health facilities.
Having a dog in the house substantially decreases the risk of asthma, as does being the youngest in a large family. But the biggest risk factor comes from events in early childhood. Children born close to the pollen season – spring – will probably develop some level of asthma later in life.