Showing posts with label Diseases. Show all posts
Showing posts with label Diseases. Show all posts

Sunday, December 8, 2019

Strange disease threatens Caribbean coral reef


The breathtaking reds, yellows and purples of the Mesoamerican Reef have been turning sickly white, leading researchers on a desperate hunt to understand and fight the mysterious disease killing the Caribbean's corals.

In a little over a year, the Mexican Caribbean has lost more than 30 percent of its corals to a little-understood illness called SCTLD, or stony coral tissue loss disease, which causes them to calcify and die.

Experts warn the disease could kill a large part of the Mesoamerican Reef, a magnificent arc of more than 1,000 kilometers of coral shared by Mexico, Belize, Guatemala and Honduras.

SCTLD has put the region in a bind: it could potentially devastate the vital tourism industry around the reef, the second-largest in the world after Australia's Great Barrier Reef.

And yet, it is highly possible that too much tourism is in fact fueling the problem, scientists say.

SCTLD, which has also been infecting coral off the coast of Florida since 2014, was first detected in the Mexican Caribbean in July last year, near the reef's northern tip.

It has since spread 400 kilometers to the south, reaching Belize and causing more coral loss than occurred in the past 40 years in the region, according to the environmental group Healthy Reefs for Healthy People.

The disease takes just weeks to kill off coral tissue that took decades to grow, said Melina Soto, the organization's coordinator in Mexico.

"If we keep going at this rate, this ecosystem is going to collapse in the next five to 10 years," she told AFP.

Brink of extinction

Scientists say SCTLD is even more dangerous than coral bleaching, another damaging condition that has affected reefs around the world, including the Great Barrier Reef.

Bleaching happens when environmental changes, such as warming ocean temperatures, cause corals -- which are colonies of tiny animals -- to expel the microscopic algae known as zooxanthellae that live inside them and give them their vibrant colors.

A reef can recover from coral bleaching if its environment recovers in time.

But SCTLD is fatal.

"It's a complete detachment of the coral tissue, which dies and leaves behind a white skeleton," said Claudia Padilla, a scientist at CRIP Puerto Morelos, a marine biology research center on Mexico's Yucatan peninsula.

To the untrained eye, the impact of the disease is not highly visible yet.

"They looked marvelous to me. I would never have thought they were dying, like the experts say," said Emanuel Fernandez, 34, an Argentine chemical engineer, after a snorkeling tour off the coast of Cancun, the region's most famous resort.

But the impact is all too visible to experts.

"You used to go diving and see these thriving colonies (of corals). Now they're all dead," said Padilla.

Twenty-five of the region's 40 coral species have been affected, she said. Of those, three are on the brink of going extinct in the region.

Researchers are currently building up a DNA bank of the endangered corals, hoping they can one day bring them back from extinction in the wild if needed.

Too much tourism?

Scientists are racing to understand what causes SCTLD.

One prime suspect is poor water quality, caused by sewage and a recent surge of decomposing sargassum seaweed -- another environmental emergency in the region.

Another likely factor is the chemicals in tourists' sunscreen, which the authorities have now banned.

"Many studies indicate that a particle found in sunscreen, oxybenzone, impedes the corals' reproduction," said Christopher Gonzalez, regional director for the national parks commission.

This month, authorities temporarily closed three sections of the reef, Palancar, Colombia and El Cielo, which receive thousands of visitors each year.

Now, government officials, the tourism industry and residents are forced to find a delicate balance: a level of tourism that will neither kill off the reef nor the economy.

Around 725,000 tourists have visited the Mexican Caribbean's reefs so far this year, a similar figure to previous years, according to officials.

"If we lose the reef, we lose our main economic activity: tourism," warned Maria del Carmen Garcia, head of the Coral Reef National Park in Puerto Morelos.

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Monday, January 21, 2019

Wild coffee facing ‘extinction’


THREE in five species of wild coffee are at risk of extinction as a deadly mix of climate change, disease and deforestation puts the future of the world’s favourite beverage in jeopardy, new research warned on Wednesday.

More than two billion cups of coffee are consumed every day, but the multi-billion-dollar industry is reliant on wild varieties grown in just a few regions to maintain commercial crop variety and adapt to changing threats posed by pests.

Scientists at Britain’s Kew Royal Botanic Gardens used the latest computer modelling techniques and on-the-ground research to predict how the 124 coffee varieties listed as endangered might fare as the planet continues to warm and ecosystems are decimated. 

On the verge of extinction

Some 75 coffee species were assessed as being threatened with extinction: 13 classed as critically endangered, 40 as endangered, including coffee arabica, and 22 as vulnerable.

“Overall, the fact that the extinction risk across all coffee species was so high – nearly 60 per cent – that’s way above normal extinction risk figures for plants,” said Aaron Davis, head of coffee research at Kew.

“It’s up there with the most endangered plant groups. In another way, it’s hardly surprising because a lot of species are hard to find, grow in restricted areas . . . some have a population only the size of a football pitch.”

Global coffee production currently relies on just two species: arabica and robusta. 

Arabica, prized for its acidity and flavour, accounts for roughly 60 per cent of all coffee sold worldwide. It exists in the wild in just two countries: Ethiopia and South Sudan. 

The team at Kew accessed climate data recorded in Ethiopia going back more than 40 years to measure how quickly the coffee’s natural habitat was being eroded by deforestation and rising temperatures.

They found that nearly a third of all wild Arabica species were grown outside conservation areas.

“You’ve also got the fact that a lot of those protected areas are still under threat from deforestation and encroachment, so it doesn’t mean they are secure,” said Davis, lead author of the research published in the journal Science Advances.
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 Farmers harvest arabica coffee beans in Gayo highland, Aceh province, Indonesia.
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https://www.hotelscombined.com/?a_aid=145054
‘Fair price’ 

As well as the inconvenience – not to mention sleepiness – consumers would face from a coffee shortfall, the authors expressed concern over the livelihoods of farmers, many of whom are being forced to relocate as climate change ravages their crops. 

“Ethiopia is the home of Arabica coffee,” said Tadesse Woldermariam Gole, senior researcher for environment, climate change and coffee at the Forest Forum. 

“Given the importance of Arabica coffee to Ethiopia, and the world, we need to do our utmost to understand the risks facing its survival.”

Davis said wholesalers needed to ensure producers were paid a fair price so they could future-proof production by investing in better growing practices and conserving a varied stock. 

In addition, governments must preserve and regenerate forests to help both wild and farmed coffee grow more easily, said the team behind the research.

Davis was keen to point out however that there is no current shortage of one of the world’s most valuable commodities.

“As a coffee drinker you don’t need to worry in the short term,” he said. 

“What we are saying is that in the long term if we don’t act now to preserve those key resources we don’t have a very bright future for coffee farming.”

 The new study found the enigmatic coffea stenophylla, known as the highland coffee of Sierra Leone, which is said to surpass arabica in flavour.

It had not been seen in the wild since 1954, and has all but vanished from coffee plantations and botanic gardens.

But a December 2018 expedition to the last known locality found a single plant followed by others after several hours of trekking.

Source - PhnomPenhPost

Monday, August 28, 2017

Floodwaters can carry deadly disease, DDC warns


People living in flooded areas have been warned to keep time spent wading through water to a minimum lest they be infected with melioidosis, a disease that has claimed 21 lives this year.

Department of Disease Control (DDC) chief Dr Jessada Chokdamrongsuk reported on Monday that 1,978 cases of melioidosis had been reported from January 1 to August 22.

The disease, caused by the bacterium Burkholderia pseudomallei and prevalent during the rainy season in the subtropics, peaks every August in Thailand and has been wider spread this year, he said. 

The bacterium thrives in contaminated water and soil and infects humans and animals through direct contact. 

“People could get infected from prolonged exposure to contaminated water or soil, especially if they have any open sores or lesions in the skin,” Jessada said. “Infection can also come from consuming contaminated water or food.” 

Melioidosis produces a variety of acute and severe symptoms, he said, including long-lasting fever with no other apparent cause, ulcers or abscesses in the lungs, liver or spleen, and blood infections. 
The disease, which mainly affects adults, can fatal, he said. Death has been known to result within 2-3 days of admission to hospital. 

Risk factors for infection include chronic respiratory and lung disease, tuberculosis, diabetes, chronic renal disease, thalassemia, cancer, and immune-suppressing conditions unrelated to HIV.

Jessada advised people coming into regular contact with floodwater to wear boots, drink only water that’s been boiled, avoid raw and partially cooked food, wash immediately after exposure and seek medical attention if a fever persists for more than five days or abscesses become chronic. 

Source - TheNation