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Pests and Diseases

CBP Agriculture Specialists encounter many different pests and diseases that pose a threat to United States agriculture, livestock and residents. See relevant USDA APHIS links for further information. 

Pests and Diseases

African swine fever is a deadly pig disease that spreads rapidly and affects domestic and wild swine. While not a threat to human health, the virus could devastate America’s swine, pork industry, and food supply. Whatever pigs mean to you—your livelihood or a pet—we’re all in it together. Protect our swine and keep the disease out of the United States.

USDA APHIS | Protect Our Pigs | Fight African Swine Fever

The Asian Citrus Psyllid (Diaphorina citri Kuwayama or ACP) causes serious damage to citrus plants and citrus plant relatives. Burned tips and twisted leaves result from an infestation on new growth. Psyllids are also carriers of the bacterium that causes Huanglongbing (HLB) disease, also known as citrus greening disease, spreading the disease to healthy citrus plants. Citrus greening is one of the most serious citrus plant diseases in the world. Once a tree is infected, there is no cure.

USDA APHIS | Asian Citrus Psyllid

The Asian longhorned beetle, or ALB, is an invasive insect that feeds on a wide variety of trees in the United States, eventually killing them. The beetle is native to China and the Korean Peninsula and is in the wood-boring beetle family Cerambycidae. Adult beetles are large, distinctive-looking insects measuring 1 to 1.5 inches in length with long antennae. Their bodies are black with small white spots, and their antennae are banded in black and white. Checking your trees regularly for this insect and looking for the damage it causes and reporting any sightings can help prevent the spread of the beetle.

USDA APHIS | Asian Longhorned Beetle - About

Avian influenza (AI) is caused by an influenza type A virus which can infect poultry (such as chickens, turkeys, pheasants, quail, domestic ducks, geese, and guinea fowl) and wild birds (especially waterfowl).  

USDA APHIS | Avian Influenza

Black stem rust is an important disease of wheat. It has a wide host range including wheat, oats, barley, rye, timothy, wild and grasses and barberry. It is caused by the fungus Puccinia graminis. The fungus is heteroecious, alternating from cereal to barberry or Mahonia. While the fungus is coexistent with wheat through out the world, the disease causes most damage in moderately moist areas and in moist seasons in areas with low average rain fall. Eradication of barberry in northern regions is an important strategy to control black stem rust. 

USDA APHIS | Black Stem Rust and Barberry

Bovine Spongiform Encephalopathy (BSE), widely referred to as “mad cow disease,” is a progressive and fatal neurologic disease of cattle. It is caused by an unconventional transmissible agent, an abnormal prion protein. 

USDA APHIS | Bovine Spongiform Encephalopathy (BSE)

This invasive pest can significantly damage and potentially kill boxwood (Buxus species) plants if left unchecked. Boxwoods are a popular ornamental evergreen shrub common to almost all landscape environments in the temperate United States. The insect is native to East Asia and has become a serious invasive pest in Europe and Canada, where it continues to spread. The caterpillars feed mostly on boxwood and heavy infestations can defoliate host plants. Once the leaves are gone, larvae consume the bark, leading to girdling and plant death.

USDA APHIS | Box Tree Moth

The brown tree snake has caused extensive economic and ecological damage to Guam. The snake is responsible for numerous power outages across the island each year and is an opportunistic feeder that has caused the extirpation or extinction of most of Guam's native forest birds and lizards.

USDA APHIS | Brown Tree Snake

Brucellosis is a contagious, costly disease.  While most often found in ruminant animals (e.g., cattle, bison and cervids) and swine, brucellosis (also known as contagious abortion or Bang's disease) can affect other animals and is transmissible to humans. The disease is caused by a group of bacteria known scientifically as the genus Brucella. 

USDA APHIS | National Brucellosis Eradication Program

Cattle Fever Ticks (Rhipicephalus (Boophilus) annulatus and R. (B.) microplus) (CFT) are important parasites of cattle due to their ability to vector Bovine babiesiosis and anaplasmosis.

USDA APHIS | Vector-Borne Diseases

Chronic Wasting Disease (CWD) is an infectious, degenerative disease of animals in the family cervidae (elk, deer, and moose, etc.) that causes brain cells to die, ultimately leading to the death of the affected animal. First recognized in Colorado in 1967, CWD was described as a clinical 'wasting' syndrome of unknown cause. It later became clear that CWD was a member of a group of diseases known as transmissible spongiform encephalopathies or TSEs. 

USDA APHIS | Cervids: Chronic Wasting Disease

Chrysanthemum White Rust, caused by the fungus Puccinia horiana P. Henn., is a quarantine significant pest in the United States. Importation of certain Chrysanthemum (including Dendranthema), Leucanthemella, and Nipponanthemum species are prohibited from several countries, territories, and possessions due to the potential of this organism to be transported with prohibited host articles.

USDA APHIS | Chrysanthemum White Rust

Citrus black spot (CBS) is a citrus disease caused by the fungus Phyllosticta citricarpa (previously known as Guignardia citricarpa). This fungus affects citrus plants throughout subtropical climates, reducing both fruit quantity and quality. All commercial cultivars are susceptible, but late-maturing cultivars and lemons are most vulnerable.

USDA APHIS | Citrus Black Spot

Citrus canker is a citrus disease caused by the bacterium Xanthomonas citri subsp. citri (synonym X. axonopodis pv. citri). While not harmful to humans, canker significantly affects the vitality of citrus trees, causing leaves and fruit to drop prematurely. A fruit infected with canker is safe to eat, but has reduced marketability as fresh fruit.

USDA APHIS | Citrus Canker

Citrus Greening (Candidatus Liberibacter asiaticus) is one of the most serious citrus plant diseases in the world. It is also known as Huanglongbing (HLB) or yellow dragon disease. Once a tree is infected, there is no cure. While the disease poses no threat to humans or animals, it has devastated millions of acres of citrus crops. 

USDA APHIS | Citrus Greening

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