After New World Screwworm was confirmed in the U.S. nearly 80 years after its eradication, experts are hoping this year’s deer hunting season will help them track the spread.

The USDA reports there are two active cases in Texas - one in Crockett County, and the other in Presidio County. 

Animals in those zones must be certified before they can be moved out of the region. A surveillance zone surrounds the infested area, where sterile flies are released as part of the response effort.

Dr. Sarabeth Hill, an assistant professor of veterinary practice in parasitology at the Texas Tech School of Veterinary Medicine, says while the spread is largely controlled, it’s harder to determine whether it’s impacting wildlife.

“I think with deer season, more people out there with eyes on animals we don’t always see, is going to be a really fantastic tool for us managing this infection,” Dr. Hill said.

While there haven’t been any reports of infections in deer so far, Texas Parks and Wildlife reports the previous outbreak in the 1950s and 60s resulted in the loss of between one third and one half of the Texas deer population. 

“Deer season will certainly be a very helpful tool for us to get a good idea of the true movement of this parasite,” Hill said.

Hill said deer open themselves up to infection more during rutting season, when they are more prone to fighting.

“Just looking at that behavior and potential for wounds, there’s a chance for those screwworm flies to take root there,” Hill said.

The New World Screwworm is attracted to live tissue, so Dr. Hill says hunters do not have to worry about their deer becoming infected after they’re shot.

She does encourage hunters to look at their deer closely, though, during processing. She says the key signs of infection are open, foul smelling wounds.

“If we see it, it’s definitely something to report to Parks and Wildlife,” Hill said. “You can just Google ‘TPWD NWS’ and it will take you to their sighting and reporting page. If you suspect anything, we as the state of Texas would rather be safe than sorry.”

Dr. Hill also added that even if you do come across a deer with an active infection, it doesn’t necessarily mean the entire animal is a waste. She said the parasite stays in the same wound track and does not spread because it relies on oxygen. 

“The nature of the screwworm is to dig into a muscle. I, personally, would discard the muscle that is affected. That open wound opens the door to secondary infection,” Hill said. “Personally, I would be okay with the rest of that deer.”

Dr. Hill said while New World Screwworm is a serious issue, state, federal, and local officials have worked hard to contain the spread.

“We have historic events to look back on and learn from that really prepared us well this year,” Hill said. “I do not think there is reason for panic. The big takeaway is: if you’re out in the field this season, and I hope lots of people are, just take an extra second to check over those animals and help us out in the effort of reducing the spread.”