Deep in the forest, Germany fights another virus. This one hits pigs.

In the mud, teeming with maggots, is the rotting carcass of a wild boar. "Hero Uschi," shouts a member of the search team. It's exactly what they spent the day hunting.

As the world fights the coronavirus pandemic, teams in Europe are battling another outbreak: African swine fever. Hundreds of miles of fencing have been thrown up in Europe to stop its steady march west across the continent, threatening the major pig farming industries in Germany and elsewhere.

While the virus cannot be passed to humans, it kills almost every pig it infects in about a week to 10 days, and it has been spreading in Europe in recent years.

In fenced off "red zones" - such as those in the forests of the Oder-Spree district southeast of Berlin - teams work to clear the area of the infectious wild boar that have succumbed to the sickness and hunt any still alive in an attempt to break infection chains.

The carcasses of the dead boars lie scattered in gullies and in wooded clearings, sending the putrid scent of decaying flesh through the forest air. The stakes are high for Germany - Europe's largest pork producer - exporting $4.7 billion in pig products each year.

The arrival of the virus in the wild boar population in Germany last year triggered bans on pork exports to countries outside Europe, wiping out $867 million in sales to China. Then in mid-July, the first case was discovered in a domestic pig farm in Germany, exactly the spread that the teams picking through the forests had been hoping to prevent.

"We are fighting the pandemic nobody knows about and nobody cares about because all eyes are on corona," said Christian Tost, a 35-year-old reservist with the German military, one of five on the 17-member search team that spent six hours scouring an area of around a square mile last month.

They found 16 dead or dying boars.

From an office in Beeskow, about 20 miles from the Polish border, Petra Senger, the head veterinarian for the Oder-Spree district, oversees operations to contain the spread. Maps of various infection zones cover the walls.

"It's a huge task," Senger said. The first dead boars were found in her district on Sept. 10, 2020. They crossed from Poland, where the virus was already rife.

In response, the local authorities fenced off an area of fields and forest the size of Belgium.

But it wasn't enough. A month later, they found new cases in an area 15 miles away and a new red zone was cordoned off.

Endemic in sub-Saharan Africa, the disease arrived in the European Union in 2014, with the first cases in Lithuania. It slowly spread to neighboring countries.

The more spread there is in wild boars, the bigger the possibility it can infiltrate pig farms, Senger said. Distancing is also important. Traps laid with corn are also set to capture boars in buffer zones.

"With people, you can ask them to wash their hands or stay at home," Senger said. "You can't tell a pig to stay home."

More hardy than the coronavirus, the African swine fever can survive in the environment for many months, and it can be spread by people through vehicles, clothing and tools. It can also live for months or years in pork products. Consumption of infected pork doesn't pose a risk to humans, but it can cause a fresh outbreak if eaten by a pig.

"We think we'll have a vaccine," Senger said. "But not until 2023 or 2024."

Meanwhile, the search teams fan out in the forests several times a week to hunt for their rotten prey, scrambling through dense thickets.

On one scorching day in mid-July, forestry personnel, hunters and dog handlers joined the 17-member team in neon vests to comb the forest, thick with pine and birch. One the dogs, Karl, a 2½-year-old dachshund, struggled with some of the denser undergrowth.

In charge was an easily angered hunter, who occasionally snapped at those lagging behind. "Do you see the people next to you?" he yelled as the forest closed in, making it more challenging to keep sights on other searchers.

They checked gullies and puddles, with dying boars drawn to water as they sicken. Circling ravens can give clues as to where boar carcasses can be found.

Leaning over the putrid remains of a boar under a log, Reiner Favre, a 53-year-old hunter, speculated that it had been there for three or four weeks.

"Maybe it was one of the first ones to get sick around here," he said. That morning there had been fresher finds, a sick boar piglet that Favre then shot, and what the group assumed to be her siblings and mother, already dead not far away.

The coordinates for each carcass are called in, with a separate team looping back to find them in the thick forest in the afternoon and load them into body bags.

They scoop up soil with the carcasses and cover the area in lime. "(The virus) can stay there for a long time otherwise," Favre said. "That's the risk of this virus. It's not a soft virus."

Even the presence of the virus in wild boar populations is a major disruption to local farmers. If dead boars are found on a farmer's land, it can affect their ability to sell their crops due to fear of contagion.

With German pork exports blocked outside the E.U., countries such as Spain have stepped in to help meet China's pork appetite. China itself has had its own struggles with swine fever, with nearly half its own herds estimated to have been wiped out by outbreaks in 2018 and 2019.

The discovery of the virus at two Brandenburg region pig farms in July was a "huge catastrophe for Brandenburg's farmers," said Tino Erstling, a spokesman for the Brandenburg State Farmers' Association. But Germany is still able to export within the E.U. from regions without the virus.

So more fences are going up. The heartland of Germany's pork industry lies in states farther west. Germany's neighbors are already working on their defenses. Denmark has constructed a 40-mile-long, five-foot-high fence along its southern border in attempts to keep out infected boars.

"We will double down on everything we've already been doing to try to stop this," Senger said. "That means finding infected pigs, building more fencing. We have to be stricter about keeping domestic and wild pigs separate."

Senger said she hopes that lakes and highways might act as natural barriers for infected boar roaming west.

"If it hits where a lot of pig farmers operate, then, of course, they will have a huge problem on their hands," said Heike Harstick, head of the German Association of the Meat Industry.

Practices in the pork industry have already come under increased scrutiny during the coronavirus pandemic. And the industry was already in decline due to a diminishing appetite in Germany for wurst and schnitzel.

Animal rights groups say that the culls are senseless, with the virus also spread by contaminated food and carried between areas by people.

For dog trainer Michaela Botz, 49, the boar hunts are a good day's work for Uschi, whose vest is made of Kevlar in case of a run-in with an angry boar. But as for containing the virus, she's not optimistic, as the group finds dead boar after boar.

"It's like a bucket without a bottom," she said.