With New World screwworm surging in Mexico before a case appeared in Florida, and with officials scrambling to contain a Pennsylvania bird flu outbreak on Feb. 17, American beef and poultry farmers grow more concerned about threats to their livelihoods.

These recent outbreaks are grabbing headlines, but farmers face many other biological threats that jeopardize the economy and food supplies.

The Farm Journal Foundation estimates that pests and diseases together have raised the cost of all food by 15% between 2022 and 2025. Consumers are bearing the bulk of that cost, pushing them into difficult choices to balance their budget. The long-term impact could be higher prices and a less secure food supply for the U.S.—and the many countries that rely on its agricultural exports.

The Farm Journal Foundation has released a report detailing 16 active and potential biological threats to American livestock and agriculture, ranging from pests to fungi and diseases. The current threat-level from these so-called “Mean Sixteen,” varies, as do efforts to control them.

Bird flu

Last year’s egg crisis appears to have abated for now, as bird flu impacts on poultry have been brought somewhat under control. The price of eggs plummeted at the beginning of 2026, with the 34.2% year-on-year decline comprising the biggest price drop in the January consumer price index. But new outbreaks are being reported in 2026, including at Pennsylvania poultry farms.

Known by the scientific name of Highly Pathogenic Avian Influenza (HPAI), bird flu’s current outbreak had caused the deaths of 169 million birds across all 50 states by April 2025, the Farm Journal Foundation report notes. This exorbitantly high death toll is due to the 75-100% mortality rate among afflicted birds, as well as the culling of healthy animals in any farm with an infected bird, to limit the spread.

The cramped conditions inside industrial poultry farms are the perfect breeding grounds: bodily secretions from one infected fowl can spread bird flu rapidly. Poultry farms are also kept at artificially elevated levels of humidity, extending the virus’ lifespan on surfaces. Bird-to-human transmission is rare, mostly limited to workers who come into contact with birds daily, but it can be highly dangerous, the report says.

Meanwhile, there are concerns about the impact on dairy farms, as bird flu increasingly impacts cattle. While there are vaccines for HPAI, the U.S. Department of Agriculture (USDA) prefers biosecurity measures for control, as it is difficult to distinguish between vaccinated birds and infected birds, making it challenging to export vaccinated birds.

New World screwworm

The New World screwworm outbreaks in Mexico are keeping the USDA on high alert.

The New World screwworm burrows into the flesh of any warm-blooded animal it comes across and lays eggs in the open wound, causing infection or death. It has been eradicated in the United States since 1966 owing to a multi-million dollar project that dumps millions of sterilized flies in infested areas to outcompete the fertile males, eventually leading to the population dying out. The project had effectively created a barrier at the Darién Gap, which straddles Colombia and Panama. While the screwworm is no longer endemic north of that line, the outbreaks in Mexico are threatening elimination status.

The U.S. livestock industry saves $900 million annually due to the screwworm’s localized eradication, according to the report. Texas’ cattle industry is particularly cautious: should screwworm return to the U.S., A&M University estimates they alone could lose up to $2.1 billion, not to mention massive losses among other livestock farmers.

The USDA is on permanent high alert to contain every case that slips past the border. In early February, the organization detected New World screwworm larvae in a horse that was exported to Florida from South America. The pests were detected during the mandatory seven-day quarantine period for horses from regions where they are present, highlighting the constant vigilance required to keep them at bay.

Existing threats

There are several other biological threats already posing challenges for U.S. farmers. Among the most severe, according to the Farm Journal Foundation, are the following:

• Citrus Greening: (Oranges, grapefruits, lemons, and other citrus crops) Spread by the Asian citrus psyllid, citrus greening is a type of fungal infection that turns infected citrus into a shade of green and renders them unpalatably bitter. While eating the infected citrus poses no known danger to humans or animals, most infected trees will die within a few years, and there is no cure, according to the report. Consumers also tend to avoid blemished fruits, leading to additional losses. While the U.S. remains one of the top 10 citrus producing countries, citrus production dropped 75% since it hit record levels in the mid-1990s—primarily due to the severe damage the Florida citrus industry has suffered in the last few decades from citrus greening, the report said.
• Codling Moth: (Apples, pears, walnuts, and other fruit and nut trees) The Codling Moth bores into various tree fruits to lay eggs, leaving a trail of excrement that renders the fruit inedible. Unmanaged infestations can destroy up to 95% of an apple or pear orchard. The moth caused serious economic losses in the past, but it has mostly been brought under control through strict management measures, the report said.
• Impatiens Necrotic Spot Virus (INSV): (Lettuce) Impatiens Necrotic Spot Virus is spread by the insect known as the Western Flower Thrip and wreaks havoc on lettuce crop yields, causing browning and death. “In the Salinas Valley of California alone, losses to lettuce producers in the 2020 crop year from INSV were estimated to be as much as $100 million,” the Farm Journal Foundation report said. Once a lettuce field is infected, there is no cure, so the main form of protection comes through preventative measures to keep the Western Flower Thrips away. Resistant varieties of crops are also being produced.
• Palmer Amaranth (Pigweed): (Corn, soybeans, and other row crops) Palmer Amaranth is a type of fast-growing weed that easily spreads its seeds over a wide area, draining the soil of nutrients needed by other crops. Row crops are especially vulnerable due to the already intensive drain on soil nutrients they require: left alone, pigweed can cause up to 91% yield loss among corn harvests, though there is no data on nationwide damage. Mowing, crop rotation, and herbicides have been shown to help counter the weed.
• Corn Ear Rot: (Corn) This fungal infection causes rust-like pustules to appear on corn stalks and a green or brown rotting on the ear itself. It is native to the Southern U.S. and Mexico, but summer winds blow spores north to the Midwestern corn belts, where they can cause substantial yield loss among fields without resistant strains or fungicide on hand. According to USDA’s National Institute of Food and Agriculture, corn ear rot infections were estimated to have cost U.S. corn producers $8.6 between 2012-23. Early detection and fungicides have been shown to contain the threat.
• Wheat Rust: (Wheat) Like Corn Ear Rot, Wheat Rust is a fungal infection that causes brownish pustules on wheat stalks, causing up to 20% yield loss. A report on wheat crop losses from diseases experienced by wheat growers found losses of 8.3% of the U.S. wheat crop and 27% in Canada in the 2024-25 crop year, amounting to a loss of about $1.8 billion between the two countries. As with corn ear rot, early detection and fungicides are essential to control.
• Rice Delphacid: (Rice) Rice Delphacids are insects that feed upon the sap of rice plants, often transmitting the Rice Hoja Blanca Virus in the process. The virus severely stunts the growth of infected rice stalks, leading to up to 75% yield loss. While there are no comprehensive estimates on the damage caused by this relatively new threat, field reporting indicates as much as 30% of the ratoon crop in Texas has already been abandoned in the 2025-26 crop year due to delphacid infestation. Farmers have tried to battle the problem using various pesticides with limited success.
• Soybean Cyst Nematode: (Soybeans) Soybean Cyst Nematodes feed on soybean roots, limiting the plant’s ability to intake food and water and increasing its susceptibility to other diseases. Given the scale of soybean cultivation in the US, the nematodes cost farmers an average of $1.5 billion annually. Crop rotation and growing resistant varieties helps to control the threat.
• Areolate Mildew: (Cotton) This type of fungal infection grows on the underside of cotton leaves in white clumps, which shed spores to transmit to other cotton plants. Once the sporulation process stops, the fungus begins to decay, causing necrotic lesions on the cotton leaves. Thus far it has had a moderate impact on the crops in Alabama, Georgia, Tennessee, and Florida, but if it spreads to other major cotton growing states such as Texas, Mississippi, and Arkansas, the impact could be more serious, according to the report. Counter measures include crop rotation, planting resistant varieties and fungicides, which are most effective when applied early.
• Porcine Reproductive and Respiratory Syndrome (PRRS): (Swine) Also known as “blue eared pig disease” after the most prominent sign of infection, PRRS causes a variety of illnesses within swine, such as sudden infertility, pneumonia, and immunodeficiency. The disease costs American pig breeders $560 million annually, the report says. While the disease cannot be cured, it can be minimized with biosecurity controls, vaccines and management of secondary infections with antibiotics.
• Enteric Septicemia of Catfish (ESC): (Catfish) ESC is a fatal bacterial infection which causes lesions on the skin and liver of infected catfish. The bacteria lay dormant within mud, which catfish unintentionally digest as part of their bottom-feeding. The costs of ESC among commercial fisheries amount to up to $45 million annually, the report says. Catfish farmers can address the situation by cleaning the environment of their fish and by crossbreeding with species that have some resistance.

Potential new threats

Farm Journal Foundation’s report identifies other “looming threats” that have not yet been reported widely in the US, but are likely to cause significant damage if they gain a foothold:

• Foot and Mouth Disease (FMD): (Cattle, swine, and other ruminants) While not usually fatal to cattle, the condition is incredibly transmissible through bodily fluids and severely limits their milk production and fertility, among other symptoms. The Farm Journal report cited research that finds a U.S. outbreak could cost nearly $200 billion to the U.S. economy if no emergency vaccination program is ready to roll out. A vaccine is available, but vaccinated livestock and infected livestock are hard to differentiate, which makes exporting a challenge.
• African Swine Fever (ASF): (Swine) Though not transmissible to human beings, ASF is lethal to pigs and has no preventative vaccine or cure. A 2021 study estimated the outbreak cost the entire Chinese economy about $111 billion, the report said. There is not yet a vaccine, though work on development is underway. For now, biosecurity measures are the best way to keep the virus under control.
• Asian Soybean Rust: (Soybeans) This fungus has spread from Asia to Africa and South America, leading to up to 80% reduced soybean yields in infected fields. It is known to be present in the U.S., particularly in the Carolinas and deep south, and is under close monitoring. The main treatment used is fungicides, but research suggests the spores can develop some resistance to commonly used fungicides, the Farm Journal Foundation report says. It cites research indicating that economic losses to U.S. producers and consumers could range between $640 million and $1.3 billion in the first year of infestation.

What must be done

Existing short-term solutions include food imports—Turkish and Korean eggs helped alleviate the egg shortage, and the Trump administration sealed a similar plan with Argentinian beef. But these solutions create new national security risks if these supplementary foreign supply lines become severed in conflict.

For the long term, new treatments are needed. The report calls for the government to increase its agricultural research and development budget, as well as strengthen its international trade measures and domestic response plans. With ample preparation, we can avoid repeats of previous shortages and develop a more resistant agricultural industry for the challenges coming ahead.