Difference between revisions of "Coxiella burnetii"

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===Case Fatality Ratio===
===Case Fatality Ratio===
The estimated case fatality rate is low,  at < 2% of hospitalized patients. Treatment with the correct antibiotic may shorten the course of illness for acute Q fever ([http://en.wikipedia.org/wiki/Coxiella_burnetii wikipedia])
The estimated case fatality rate is low,  at 1-2% of hospitalized patients.<ref name=Parker>Parker, N. R., Barralet, J. H., & Bell, A. M. (25 February). Q fever. The Lancet, 367(9511), 679–688. doi:10.1016/S0140-6736(06)68266-4 [Http//:www.sciencedirect.com/science/article/pii/S0140673606682664 Full Text]</ref>
===Incubation periods===
===Incubation periods===

Revision as of 18:39, 24 May 2012

Coxiella burnetii


Animal and human

Transmission/Exposure Routes

Infection of humans usually occurs by inhalation of these organisms from air that contains airborne barnyard dust contaminated by dried placental material, birth fluids, and excreta of infected animals

Case Fatality Ratio

The estimated case fatality rate is low, at 1-2% of hospitalized patients.[1]

Incubation periods

The acute symptoms usually develop within 2-3 weeks of exposure, although as many as half of humans infected do not show symptoms (CDC)

Burden of Disease

Q Fever became a reportable disease in the United States in 1999. Between 2000 and 2004, the US saw an average of 51 cases every year. In 2005, 136 cases were reported to the CDC, and 169 in 2006.[2]
The annual has been reported as 0.28 cases per million persons[2]
Internationally, prevelance is estimated from 5% in urban areas to 30% in rural areas. This is likely an underestimate due to asymptomatic infections. Results of serological testing of blood donors revealed a prevalence of 18% to 37% in Africa. The United Kingdom sees approximately 100 cases of Q Fever a year (Struble, K. 2012).

Duration of infectiousness and disease


Most patients (50-60%) infected with Q fever are asymptomatic. Those who do show symptoms present flu-like symptoms including fevers, coughs, sweats, myalgias, and arthralgias. Other possible symptoms are pneumonia and hepatitis.[3]


Asymptomatic Rates

Excretion Rates (see Exposure)



Obligate intracellular small Gram-negative bacteria

Environmental Survival

The organism is extremely hardy and resistant to heat, drying, and many common disinfectants which enable the bacteria to survive for long periods in the environment

Recommended Dose Response Model

Dose response models for Coxiella burnetii
Beta-Poisson: α is 0.36, N50 is 4.93E+08
Betapoisson model.jpg


Struble, K. Cunha, B. (2012) "Q Fever" Medscape Reference. Retrieved on 2-1-2012 from http://emedicine.medscape.com/article/227156-overview#a0156

  1. Parker, N. R., Barralet, J. H., & Bell, A. M. (25 February). Q fever. The Lancet, 367(9511), 679–688. doi:10.1016/S0140-6736(06)68266-4 [Http//:www.sciencedirect.com/science/article/pii/S0140673606682664 Full Text]
  2. 2.0 2.1 McQUISTON, J. H., Holman, R. C., McCALL, C. L., Childs, J. E., Swerdlow, D. L., & Thompson, H. A. (2006). National Surveillance and the Epidemiology of Human Q Fever in the United States, 1978–2004. The American Journal of Tropical Medicine and Hygiene, 75(1), 36–40. Full Text
  3. Hartzell, J. D., Wood-Morris, R. N., Martinez, L. J., & Trotta, R. F. (2008). Q Fever: Epidemiology, Diagnosis, and Treatment. Mayo Clinic Proceedings, 83(5), 574–579. doi:10.4065/83.5.574 Full Text