Brucella

Brucella spp. Gram negative, coccobacilli bacteria Facultative, intracellular organism Environmental persistence Temperature, pH, humidity Frozen and aborted materials Multiple species

Species Biovar/Serovar Natural Host Human Pathogen B. abortus 1-6, 9 cattle yes B.melitensis 1-3 goats, sheep B. suis 1, 3 swine 2 hares 4 reindeer, caribou 5 rodents B. canis none dogs, other canids B. ovis sheep no B. neotomae Desert wood rat B. maris (?) marine mammals ?

The Many Names of Brucellosis Human Disease Malta Fever Undulant Fever Mediterranean Fever Rock Fever of Gibraltar Gastric Fever Animal Disease Bang’s Disease Enzootic Abortion Epizootic Abortion Slinking of Calves Ram Epididymitis Contagious Abortion

History of Malta Fever 450 BC: Described by Hippocrates 1905: Introduction into the U.S. 1914: B. suis Indiana, United States 1953: B. ovis New Zealand, Australia 1966: B. canis in dogs, caribou, and reindeer

History Alice Evans, American bacteriologist Credited with linking the organisms Similar morphology and pathology between: Bang’s Bacterium abortus Bruce’s Micrococcus melitensis Nomenclature today credited to Sir David Bruce Brucella abortus and Brucella melitensis

Transmission to Humans Conjunctiva or broken skin contacting infected tissues Blood, urine, vaginal discharges, aborted fetuses, placentas Ingestion Raw milk & unpasteurized dairy products Rarely through undercooked meat Incubation varies 5-21 days to three months

Who is at Risk? Occupational Disease Hunters Travelers Cattle ranchers/dairy farmers Veterinarians Abattoir workers Meat inspectors Lab workers Hunters Travelers Consumers of unpasteurized dairy products

B. melitensis Latin America, Middle East, Mediterranean, eastern Europe, Asia, and parts of Africa Accounts for most human cases In the Mediterranean and Middle East Up to 78 cases/100,000 people/year Arabic Peninsula 20% seroprevalence Recent emergence in cattle on Middle Eastern intensive dairy farms

B. abortus Worldwide Some countries have eradicated it Notifiable disease in many countries Poor surveillance and reporting due to lack of recognition Fever of Unknown Origin (FUO)

Brucellosis in U.S.: 1975-2006

Human Disease Can affect any organ or organ system All patients have a cyclical fever Variability in clinical signs Headache, weakness, arthralgia, depression, weight loss, fatigue, liver dysfunction

Human Disease 20-60% of cases Hepatomegaly may occur Osteoarticular complications Arthritis, spondylitis, osteomyelitis Hepatomegaly may occur Gastrointestinal complications 2-20% of cases Genitourinary involvement Orchitis and epididymitis most common

Human Disease Neurological Cardiovascular Depression, mental fatigue Cardiovascular Endocarditis resulting in death Chronic brucellosis is hard to define Length, type and response to treatment variable Localized infection Blood donations of infected persons should not be accepted

Human Disease Congenitally infected infants Low birth weight Failure to thrive Jaundice Hepatomegaly Splenomegaly Respiratory difficulty General signs of sepsis (fever, vomiting) Asymptomatic

Diagnosis in Humans Isolation of organism Serum agglutination test Blood, bone marrow, other tissues Serum agglutination test Four-fold or greater rise in titer Samples 2 weeks apart Immunofluorescence Organism in clinical specimens PCR

Treatment of Choice Combination therapy has the best efficacy Doxycycline for six weeks in combination with streptomycin for 2-3 weeks or rifampin for 6 weeks CNS cases treat 6-9 months Same for endocarditis cases plus surgical replacement of valves

Yersinia pestis

Yersinia pestis Yersinia originally classified in Pasteurellaceae family Based on DNA similarities with E. coli, Y. pestis is now part of Enterobacteriaceae family 11 named species in genus  3 are human pathogens Y. pestis, Y. pseudotuberculosis, Y. enterocolitica Y. pestis and Y. pseudotuberculosis rarely infect humans Y. enterocolitica is the cause of 1 – 3% of diarrhea cases caused by bacteria

Yersinia pestis Gram-negative bacteria Can grow with or without oxygen Most commonly found in rats but also found in: Mice, squirrels, fleas, cats, dogs, lice, prairie dogs, wood rats, chipmunks

Types of Plague Bubonic Plague Pneumonic Plague Septicemic Plague Most common Infection of the lymph system (attacks immune system) Pneumonic Plague Most serious type of plague Infection of the lungs leading to pneumonia Primary and Secondary Septicemic Plague Bacteria reproduces in the blood Can be contracted like bubonic plague but is most often seen as a complication of untreated bubonic or pneumonic plague

Diagnosis and Treatment Symptoms Most cases of plague are diagnosed initially from presented symptoms, especially Bubonic plague. If plague is suspected, blood work is completed to determine how far the plague has progressed and to determine antibiotic resistances. Since no major antibiotic resistances have developed, plague is usually treated with Streptomycin. Other antibiotics that can be used are: tetracyclines, fluoroquinolones and other aminoglycosides. Antibiotics are administered to the patient as well as to those who are believed to have been exposed. Symptoms Bubonic Fever, headache, chills, weakness, swollen and tender lymph glands Pneumonic Fever, headache, weakness, rapid onset of pneumonia (usually accompanied by: shortness of breath, chest pain, cough, bloody or watery sputum) Septicemic Fever, chills, weakness, abdominal pain, shock, bleeding underneath skin or other organs

http://rarediseases. about http://rarediseases.about.com/od/infectiousdiseases/ig/Pictures-of-Bubonic-Plague/hand-gangrene.htm

Transmission Bubonic and Septicemic can not be transferred human to human. They can only be contracted if bitten by an infected rodent or flea. Pneumonic can be transferred through exposure to infected particles. This usually occurs when in close contact with someone who is infected and is exposed to sputum that is coughed up.

http://www.unbc.ca/nlui/wildlife_diseases_bc/plague_cycles.gif

History There have been three major pandemics of the plague. Mid 6th century, mid 14th century, early 20th century The most well known plague pandemic was in the mid 14th century in Europe known as the Black Death The plague came from Asia and spread through Europe in two years. In the two years, it killed more than half of the population. People didn’t understand how the plague worked which allowed it to spread . Benefits.

Sedlec Ossuary in Kutna Hora http://neatorama.cachefly.net/images/2005-12/sedlec-ossuary.jpg http://z.about.com/d/goeasteurope/1/0/o/5/-/-/SedlicOssuary11.JPG http://www.earth-photography.com/photos/Countries/CzechRepublic/Czech_KutnaHora_Ossuary1.jpg

Incidence Considered a re-emerging disease. Incidence is on the rise: 2,000 to 3,000 cases a year worldwide. http://www.cdc.gov/ncidod/dvbid/plague/world98.htm