Other Exposures and Medical Conditions

Infectious Diseases
There are many zoonoses (infectious diseases that are spread from animals to man) that are a risk 
to people working in agriculture.  These diseases do cause illness but they are generally not fatal.  
There is increased concern about agricultural zoonotic diseases that are linked to bioterrorism and 
include anthrax, tularemia, and Q fever.  These are relatively uncommon diseases but the rural 
practitioner should be aware of the presentation of the diseases that may occur in agriculture.  
There is not adequate space for full discussion but an overview will be given.

Some infectious zoonotic diseases may be mistaken for the common atypical pneumonias.  These 
include ornithosis (psittacosis) that can be contracted from poultry, primarily ducks and turkeys.  
Swine influenza can be passed from swine to humans but generally is not as severe as Influenza 
A or B.  Q fever is a respiratory disease from ungulates whose hardy viable forms can be 
transmitted in blowing dust a mile away.  Placental tissue from sheep is a primary source.  Anthrax 
can present in three clinical forms cutaneous, (image) gastrointestinal, or the fatal pulmonary form.  
Cattle and swine are sources of anthrax.  Brucellosis causes a waxing and waning fever and 
respiratory symptoms and can be contracted from cattle and swine.  Leptospirosis is spread by 
animal contaminated water and can cause influenza like illness and symptoms of meningitis.  
Ongoing surveillance programs exist in each state to maintain disease free herds by quarantine 
and destruction of infected animals.


Other arising diseases of concern include:
o  Hepatitis E from swine - endemic in Mexico and spread by fecal-oral exposure
o  Cryptosporodiosis - a protozoan shed by calves and a risk to immune-compromised individuals
o  Enteric gram negative pathogens with bacterial resistance - gastrointestinal diseases	
o  Streptococcus suis - from swine, skin disease in mild cases, meningitis in severe cases
o  Mad Cow disease (Creuzfeld-Jakob Disease) - spread by feeding garbage with animal remains to 
    cattle and infecting with prions-not identified in the U.S. as related to agriculture
o  Foot and mouth disease - in animals only, not related to the Coxsackie virus that 
    commonly causes hand-foot-mouth disease in children.

Several other diseases are of concern to the farming population who spend a great amount of time 
outdoors.  In Minnesota these diseases include rabies, Lyme Disease and other tick borne 
diseases. Another potential disease is Hanta Pulmonary Syndrome, caused by the Sin Nombre virus, 
spread by white-tailed deer and deer mice.  Other zoonotic diseases cause dermatologic symptoms 
including milkers nodules from cattle, erysipeloid from sheep, dermatophytic infections (ring worm), 
and Orf (ecthyema contagiosum).  

Selected Zoonotic Diseases found in the Midwest.