“Virus hunters” track threats to avert the next pandemic

BANGKOK (AFP-Jiji) – A global network of doctors and laboratories is working to detect emerging viral threats, including many caused by climate change, to avert the next global pandemic.

The coalition of self-proclaimed “virus hunters” has uncovered everything from an unusual tick-borne illness in Thailand to a surprise outbreak of a mosquito-borne infection in Colombia.

“The list of things we have to worry about, as we've seen with COVID-19, is not static,” said Gavin Cloherty, an infectious disease expert and head of the Abbott Pandemic Defense Coalition.

“We have to be very vigilant about how the villains we know about are changing… But also whether there are new kids on the block,” he told AFP.

The coalition brings together doctors and scientists at universities and healthcare institutions around the world and is funded by healthcare and medical device giant Abbott.

By uncovering new threats, the coalition gives Abbott a potential head start in developing the testing kits that have been central to the COVID-19 response.

And his involvement gives the coalition major financial resources and the ability to detect and sequence new viruses, as well as respond to them.

“If we find something, we can do industry-level diagnostic testing very quickly,” Cloherty said.

“The idea is to contain an outbreak so we can hopefully prevent a pandemic.”

The coalition has sequenced approximately 13,000 samples since operating in 2021.

An outbreak of Oropouche, a mosquito- and midge-borne virus that had previously been rarely observed there, has been detected in Colombia.

Phylogenetic studies tracing the strain's family tree revealed that it originated in Peru or Ecuador, rather than Brazil, another hotspot.

“You can see where things are going. It’s important from a public health perspective,” Cloherty said.

Difficult and costly

Recently, the coalition worked with doctors in Thailand to uncover that a tick-borne virus was behind a mysterious cluster of patient cases.

“At that time, we did not know which virus caused this syndrome,” explained Pakpoom Phoompoung, associate professor of infectious diseases at Siriraj Hospital.

Testing and sequencing of samples from 2014 found that many of them were positive for severe fever with thrombocytopenia syndrome (SFTSV).

“Less than 10 patients had [previously] “I was diagnosed with SFTSV in Thailand… we don't have PCR diagnosis, we don't have serology for this viral infection diagnosis,” Pakpoom told AFP.

Diagnosis “is difficult, labor-intensive and also expensive.”

And there is a growing need to track these threats as climate change expands the spectrum of infectious diseases worldwide.

The connection between climate change and infectious diseases is well established and diverse.

Warmer conditions allow vectors like mosquitoes to live in new locations, more rain creates more breeding grounds, and extreme weather forces people to spend time outdoors where they are more vulnerable to bites.

Human impact on the planet also drives the spread and evolution of infectious diseases in other ways: loss of biodiversity forces viruses to evolve into new hosts and can lead to animals coming into closer contact with humans.

“You have to be vigilant”

The phylogenetic analysis of the SFTSV strain in Thailand provides insight into the complex interplay.

It turned out that the virus had evolved from a tick with a smaller geographical range into the more resistant Asian longhorn tick.

The analysis found that their evolution was driven largely by the use of pesticides that reduced the number of original tick hosts.

Once the virus has evolved, it could spread further, in part because Asian longhorn ticks can live on birds that travel farther and faster due to changing climate conditions.

“It’s almost like they’re an airline,” Cloherty said.

The traces of climate change can be found in everything from record-breaking dengue outbreaks in Latin America and the Caribbean to the spread of West Nile virus in the United States.

While the coalition grew from work before the pandemic, the global spread of COVID-19 was a stark reminder of the risks of infectious diseases.

But Cloherty fears people are already forgetting those lessons.

“You have to be vigilant,” he said.

“Something that happens in Bangkok could happen in Boston tomorrow.”