Armed with air samplers, rope tricks, and—yes—ants, virus hunters spot threats in new ways

There were pots and pans, phone cords, radios, hats and dresses for sale at the Orussey market on a Friday morning last year. Dozens of roasted pigs hung on hooks, crabs the size of two fists filled buckets, and stacked fruit and dried fish formed mountains on tables.

He came for the live poultry because he didn't want a dinner. He was an Epidemiologist at Cambodia's Pasteur Institute. He had a cellphone in one hand and a device that looked like a credit card reader in the other, but he didn't have anything else with him. The AeroCollect uses an electric field to trap air in tiny chambers. When he returned to his lab, he flushed each chamber with a water rinse and ran aPCR to amplify any viral RNA in the air.

There are many researchers looking for simpler, faster, cheaper, and safer ways to find viruses. He won't have to wear masks and gloves if the AeroCollect works well. The device will be flown into bat caves so researchers don't have to enter them.

A more timely, deeper understanding of potential threats is one of the things other scientists are trying to improve. Wastewater programs have shown how new methods can be used to help.

The World Health Organization welcomes many of the projects that are at the proof-of-concept stage. Van Kerkhove was part of a project on bird flu that included sampling birds at the Orussey market. Air sampling is leaps and bounds in technology

What Van Kerkhove calls a stamp collecting exercise, is simply identifying the hundreds of thousands of viruses in wild and captive animals. She says detection is only one part. Is the virus capable of entering humans? What does that mean? Does it have an epidemic risk or is it dead? The Global Virome Project, an ambitious scheme that promises to find the vast majority of pathogens that threaten humans but has struggled for many years to find the funding to launch, has been criticized due to this.

Christine Johnson, who directs the EpiCenter for Disease Dynamics at the University of California, says that to properly gauge the risk of an outbreak, researchers have to conduct repeated infections in hot spots such as live- animal markets, farms, and bat caves. She thinks we don't want to do a snapshot in time. Watching things evolve to really gain any true insight or understanding is what it has to be.

A bit of ingenuity and creativity can make it easier to identify threats. They are looking at some of the avenues.

Johnson's team is giving the monkeys something to eat. Scientists might be able to sample the saliva of animals using treats on ropes.

The project grew out of the U.S. government's PREDICT, a 30 country effort launched in 2009. Sampling wild primate involves trapping and anesthetizing them. Some scientists have collected feces or urine because of ethical and practical issues. Direct observation or access to the animals' nest in trees are both drawbacks of those approaches.

Johnson and Evans tested ropes with treats that monkeys chew on, leaving behind gobs of saliva. The simian foamy virus, parainfluenza 3, enteroviruses, and herpesviruses were found in Uganda and Nepal. The group collected plants that were chewed and discarded by Uganda's mountain gorillas in order to determine if people were infecting them with the human herpesviruses-1. The team reported in the American Journal of Primatology that there were gorilla-specific herpesviruses found in the plant discards.

There are more futuristic projects in the works. A team is trying to figure out if a sandwich-size air sampler can identify active viral infections in humans from their breath. Researchers have found that several respiratory diseases have specific breath signatures. Breath markers were reported during the spread of the Delta and Omicron variant by a UC Davis team. The group tested the ability of the air sampler to detect disease signatures while attached to a person's hip.

Despite a surge of interest during the Pandemic, the field ofbreath biopsy is still in its infancy. The Netherlands used breathalyzers for COVID-19 testing, but they weren't reliable. Davis and an international group of colleagues launched the Human Breath Atlas to conduct large-scale investigations into the rare VOCs people exhale when sick.

In the Netherlands, veterinarians have been placing cloths in chicken barns to collect dust that can be analyzed for diseases. She says there isn't much highquality information on animal health. We're looking at ways to make it easier to observe.

According to a 2017 estimate, there are 22 billion chickens in the world and they have dangerous viruses that sometimes spill over into humans and cause the next Pandemic. The usual way to look for avian viruses is to compare the dust from the farms with the feces from the chickens. They used metagenomics to sequence any genetic material in the sample. The group reported in Scientific Reports last year that samples from both sources yielded the same results.

Scientists hope the technique can help predict trouble. She says that the way our surveillance works is very fast paced. How can we pick up diseases before they become a problem?

Some Virginia hunters would like to send in an army. The army ants can travel up to 1 kilometer a day in and out of dense forests that researchers can't easily enter. The team led by Philippe Roumagnac at the University of Montpellier wondered if the ants picked up the pathogens infecting their meals. Roumagnac and his colleagues took army ants from 29 different colonies of the genera Dorylus and ground them up to conduct a metagenomic survey. The group reveals in a preprint that there are 157 different viral genera. What species the ants ate can be revealed through metagenomic analyses. Roumagnac says that using ants doesn't have a sampling bias.

To verify the method, the team plans to sample bat guano for Viruses and compare them with what they find in army ants. One of the key players that could give clues about the bigger picture of the ecology and evolution of viruses is army ants.

There is a lot of toys in the office that might expand the AeroCollect's capabilities. Even caves that only rock climbers can reach could be sampleed by a drone. He plans to use the remote-controlled car to collect samples from distant farms. The analysis will be accelerated by the use of portable and battery-powered devices. The lab is going to be brought to the field by us. We can get ahead of it quicker if we are at an outbreak.

In Cambodia, the Pasteur team has a long history of working on how bird flu can evolve and spread to humans. Despite an investment of more than $200 million, PREDICT did not identify the threat of SARS- CoV-2. Political will and acceptance by local people who don't accurately perceive the risk are required for preventive measures.

There is no reason not to try. He wants to know if we can prevent epidemics. We can be better prepared for the next one.