Climate & environment

 

Tropical diseases on their way to Sweden

Agneta Elmegård

Published 16.14

 

The Asian tiger mosquito is about to gain a foothold in Sweden. Photo: Lund University

Global warming means that diseases such as West Nile fever, NTM infections and new tick-borne viruses are about to establish themselves in Sweden. Region Skåne has started to prepare.

- It's not about when we get our first case of West Nile fever, say researchers at Lund University.

Tropical diseases are a group of infectious diseases caused by parasites, mosquitoes, worms, bacteria or viruses. In order for them to be able to establish themselves and spread, it needs to be warm and humid and above all they spread in tropical and subtropical parts of the world. But global warming means that today it is an average of 1.5 degrees warmer and ten percent wetter during the summer months in Sweden, compared to in the 90s. This means that some tropical diseases have taken hold in Europe and are getting closer and closer to us in Sweden.

People are affected by new diseases and challenges to the healthcare system are increasing. Among other things, everything is prepared to start screening blood donors for West Nile fever in Region Skåne.

- In Skåne, we have rapid tests for dengue fever for people who have been infected abroad. We have not had any domestic cases of these diseases and the Asian tiger mosquito is not found in Sweden yet, but we diagnosed 13 people last year as a result of travel in Asia, South America and Africa, says Gülsen Özkaya Sahin, in a press release. She is senior physician at Clinical Microbiology and Care Hygiene at Labmedicin Skåne and docent in virology at Lund University.

In 2022, 71 people were infected with dengue in Europe, and globally around 400 million people are infected with the disease every year. Although the symptoms of the disease are generally mild the first time you get sick, they put a heavy burden on the healthcare system.

According to mosquito researcher Anders Lindström, the Nile fever mosquito has been present in Sweden since 2016. We haven't had a case of the disease yet, but considering the ongoing global warming, it's only a matter of time before we get our first case, says Gülsen Özkaya Sahin.

- Unlike our usual mosquitoes that thrive in the shade and don't like sun and wind, the Nile fever mosquito flies around the clock and is quite agile.

The virus has its reservoir in birds and is spread by blood-sucking female mosquitoes. Humans and horses can also be infected, but due to the very short-lived and low-grade virus level, the infection cannot spread further. This is why people and horses are called "dead end hosts". But there are exceptions. The virus can spread between people via blood transfusion, organ transplantation and during pregnancy and breastfeeding.

- In 80 percent it is a silent disease, but a fifth get flu-like symptoms with or without a skin rash. In less than one percent, however, the disease is serious with signs of meningitis. Patients with neuroinvasive diseases also have a higher mortality rate.

During the period July-November each year there are regional outbreaks of West Nile fever in various countries in Europe. The blood centers in Sweden currently handle this with a four-week travel clearance. Since there are cases of West Nile fever as high in Europe as in Germany, Region Skåne has now prepared a contingency plan with screening of blood donors.

Source: Lund University

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New study: "Global warming is increasing at an unprecedented rate"

Christina Nordh

Updated 13.45 | Published 10.15

A man distributes water for free in the Indian city of Hyderabad in March 2024. At the time, it was the country's tenth consecutive record-warming month. A week ago, the temperature reached 49.9 degrees in the capital Delhi. The record stands at 51 degrees and was measured in the state of Rajasthan in 2016. Photo: Mahesh Kumar A. / AP

The window is about to close.

Soon it may be too late to slow the rising temperatures.

Global warming has accelerated at an "unprecedented" rate, according to a new study.

According to the 50 scientists behind the study, which was published in the journal Earth System Science Data, temperatures rose by 0.26 degrees Celsius from 2014 to 2023.

During the same period, average global surface temperatures were 1.19 degrees Celsius above the 1850–1900 reference point used to measure a warming world. It is an increase from the 1.14 degrees reported last year for the decade until 2022, writes the AFP news agency.

- The human-caused warming has increased at a rate that is unparalleled, the study reads.

The study is an annual update on the state of the climate meant to fill the gap between IPCC reports released on average every six years since 1988. The study was released during mid-term climate talks ahead of the COP29 summit in Baku, Azerbaijan in November.

Under the 2015 Paris Agreement, the world's countries agreed to limit global warming to below 2 degrees Celsius above pre-industrial levels, with a goal of not exceeding 1.5 degrees.

According to the new report released Wednesday, human activity pushed temperatures up 1.31 degrees above pre-industrial levels last year. In total, the earth warmed up to 1.43 degrees Celsius together with weather phenomena such as El Niño.

The reduction of polluting particles in the atmosphere that reflect some of the sun's energy back into space is another factor contributing to the warming, according tothe study.

- The biggest reason is that air pollution has been cleaned up, first of all in Europe and the USA - and recently in Asia, above all in China, says Glen Peters from Cicero, Center for international climate research in Norway, to the AFP news agency.

But the main driving force for global warming was "greenhouse gas emissions, which are at a historically high level," according to the study.

Average annual emissions for the period 2013–2022 were 53 billion tonnes of carbon dioxide and the equivalent in other gases – mainly from the use of fossil fuels such as oil and gas, the report states.

In 2022, emissions amounted to 55 billion tonnes. That means the world's carbon budget - the estimated amount of greenhouse gases that can be emitted before the planet drifts above the 1.5°C limit - is "shrinking rapidly", the study warned.

In 2020, the IPCC estimated that the remaining carbon budget was in the range of 500 billion tons of carbon dioxide. By early 2024, the budget had shrunk to around 200 billion tonnes, the study said.

The report's lead author Piers Forster says there is hope, at least in one finding. The rate of increase in emissions over the past decade appears to have slowed since 2000. Forster believes this signals that "we are not necessarily going to have a large, incremental acceleration of climate change".

The study's co-author Pierre Friedlingstein said at a press conference that stopping is not enough to avoid climate change.

- We do not need stabilized emissions. We need reduced emissions to net zero. As long as emissions continue to be at the same level, warming will continue at the same level, he says.

Without sweeping changes in emissions, the 1.5-degree target will be exceeded and become a "long-term average" within the next decade, according to Friedlingstein,