America's cattle herds are now threatened by a tick-borne epidemic of bovine "yellow fever" that kills huge numbers of adult cattle and can spread to humans if not treated.

The China trade war and floods have devastated agricultural interests across the America's Midwest this year.  But a few days of sun last week allowed corn farmers to plant 19 percent more acres, bringing their total to 68 percent of plan, and soybeans farmers planted 11 percent more acres, bring their total to 30 percent of plan.

But the good news was submarined by reports from the Centers for Disease Control of a widespread epidemic of bovine anaplasmosis, commonly referred to as "yellow fever."

According to the Hindawi Interdisciplinary Perspectives on Infectious Diseases, bovine anaplasmosis is endemic in Mexico, Central America, South America, and the Caribbean Islands.  It has now been reported in every state within the United States.

Caused by parasitic tick bites and unsterilized vaccinations needles, "yellow fever" caused major losses for U.S. beef-producers in the 1960s and 1970s.  Cattle losses over the last decade have averaged $100 million a year due to anemia, fever, weight loss, jaundice, uncoordinated movements, spontaneous abortion, and death in adult cattle.

Kansas State University professor Dr. Hans Coetzee advised that a 2010 study of newly infected dairy herds in Kansas found that 34 percent of the lactating cows died, and milk production fell by 44 percent.  He warned that infections accelerated after 2015.

A new statewide study by Kansas State veterinarian Mark Spare, covering 925 herds and 9,250 head of cattle, found infection in about 83 percent of the herds in eastern counties, 47 percent of herds in central counties, and 22 percent in the western counties.

Spare advised that the research results indicate that Kansas has a prevalence of anaplasmosis infection at the cow herd level in every region of the state, and infection concentrations are multiplied by commonly used animal management practices.

Oklahoma State University veterinarian Dana Zook told VitaFirm that in his state:

Cattle 1 to 3 years of age may exhibit severe clinical signs, but their ability to recover from the disease is more likely than older animals. Data indicate that 30 percent to 50 percent of infected cattle more than three years of age will die without early treatment.

The Centers for Disease Control reported that U.S. bovine anaplasmosis became cross-species by mutating into human granulocytic anaplasmosis (HGE) around 2000.  Averaging about 500 cases a year in its first decade, HGE jumped to 3,656 cases in 2015 and 5,762 cases in 2017, the latest year data. 

HGE has been most prevalent in rural states with lots of agriculture such as Arizona, Florida, Illinois, Kansas, Kentucky, North Carolina, Ohio, Oklahoma, South Dakota, Utah, and West Virginia.  But in 2016, five separate confirmed cases of HGE were reported to the California Department of Public Health in the counties of Alameda, Kern, Sacramento, San Mateo, Tulare, and Ventura as the result of tick bites.