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A Sample of Q Fever Information
by
Keith Smith
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Q fever is a bacterial zoonotic (capable of being transmitted from animals to people) disease caused by Coxiella burnetii, a rickettsial organism.
C. burnetii may be found in sheep, cattle, goats, cats, dogs, some wild animals (including many wild rodents), birds, and ticks. Animals shed the organism in their urine, feces, milk, and especially in their birth products.
Q fever cases in humans is a mandatory reportable disease in most areas. Contact your local, regional or national health department for instructions.
Natural History of Q Fever in Goats
Todd Hatchette
The Department of Medicine, Dalhousie University, Halifax, Nova Scotia
Nancy Campbell, Robert Hudson, Didier Raoult, Thomas J. Marrie
March 2003, Vol. 3, No. 1, Pages 11-15
Posted online on July 9, 2004.
(doi:10.1089/153036603765627415)
During the spring of 1999, an outbreak of Q fever resulted in 30 abortions among 174 (17%) goats in a caprine cooperative in Newfoundland. The intent of this study was to determine the natural history of Coxiella burnetii infection in goats.
Twenty-four goats on one farm were followed through the next two kidding seasons following the Q fever outbreak. Antibodies to phases I and II C. burnetii were determined using an indirect immunofluorescence assay and samples of placentas were cultured for C. burnetii and polymerase chain reaction was used to identify C. burnetii DNA. Phase I antibody was present in high levels and was maintained over the study period, while phase II antibody levels declined to the seronegative range in 60% of the infected goats. Molecular studies suggest that excretion of C. burnetii in the placenta of infected goats seems to be limited to the next kidding season following an outbreak.
We therefore conclude that C. burnetii infection in goats seems to be limited to two kidding seasons. Phase I antibody levels are maintained, while phase II antibody levels decline.
From the Merck Veterinary Manual
Q-fever is a rickettsial infection that is usually unapparent but can cause abortion in sheep, goats, and cattle, and an influenza-like disease that may result in chronic endocarditis in man. The risk of infection in man is greatly increased in occupations involving direct or indirect contact with infected animals. Several cases of Q-fever have occurred in personnel and human patients in medical institutions where latently infected sheep were used for research. People apparently acquired infection by inhalation of airborne infectious agents. Recently, parturient cats have been identified as a source of infection for people.
Etiology, Epidemiology, and Transmission: The causative rickettsia, Coxiella burnetii , is distributed worldwide and has been found in various wild and domestic mammals, arthropods, and birds. Domestic cattle, sheep, goats, dogs, and cats are susceptible to infection, and the disease is found in most areas where cattle, sheep, and goats are kept. Ixodid and argasid ticks can be reservoirs of the organism.
The epidemiology is complex because there are two major patterns of transmission; in one, the organism circulates between wild animals and their ectoparasites, mainly ticks; the other occurs in domestic ruminants, independent of the wild animal cycle.
Coxiella burnetii is highly resistant to physical and chemical agents and can survive weeks to years in the environment. The organism can be spread to other animals and people through aerosolization of infected particles, by direct contact, or by ingestion of placentas or other reproductive discharges or milk. Based on epidemiologic evidence, ticks may transmit the disease among domestic ruminants and occasionally to people. The most important mode of transmission from domestic ruminants to people is airborne via dust particles from desiccated reproductive fluids; however, obstetrical procedures and raw milk are also involved. High-temperature pasteurization effectively kills the organism.
Clinical Findings and Diagnosis: Infection is usually subclinical but can cause anorexia and abortion in sheep and goats. Reports have implicated C. burnetii as a cause of infertility and sporadic abortion in cattle. Once a domestic ruminant is infected, C. burnetii can localize in mammary glands, supramammary lymph nodes, placenta, and uterus, from which it may be shed in subsequent parturitions and lactations. There is no published information on the course of disease in infected cats.
In domestic ruminants, gross lesions are nonspecific, and differential diagnosis should include infectious and noninfectious agents that cause abortion. The complement fixation test is done most commonly; agglutination and immunofluorescence tests and microscopy of stained tissues also may be diagnostic. Recovery of the organism poses a threat to laboratory personnel.
Treatment and Control: A vaccine for animals (not currently available in the USA) has prevented infection when administered to uninfected calves and has improved fertility and reduced shedding in previously infected animals. For treatment, tetracycline is the drug of choice, but it is not as effective as in treatment of other rickettsioses; chloramphenicol is also effective. Segregation of pregnant animals and burning or burying reproductive offal can greatly reduce spread of the organism.
NHS Direct Online Health Encyclopaedia
Q Fever
Introduction
Q-Fever first appeared in Australia during the 1930s when workers at a
Brisbane meat processing plant became ill with a fever.
Q fever comes on suddenly. The name of the disease arose before the cause was known. 'Q' stands for 'query'. Fewer than 1% of patients die from it, even if they don't have treatment. If they take antibiotics, the percentage is much less.
There is an effective vaccine against Q fever.
Symptoms
Q fever symptoms are usually: a severe headache, a fever of 104 degrees F or higher with shaking chills, general malaise, muscle pain and achiness, chest pain, and sometimes pneumonia and hepatitis.. Humans are usually infected by breathing in the infection. The disease is carried by cattle, sheep, goats, and ticks. The bacteria can survive for long periods in the environment, so it poses a continuing health hazard once it is disseminated.
Q fever starts with a high fever that lasts for up to three weeks, severe headache, muscle and chest pain and a cough. In the second week of the illness a form of pneumonia develops, but the patient usually recovers.
Sometimes the Q fever lasts a very long time. In such cases, one-third of the people affected develop liver inflammation (hepatitis) and some suffer inflammation of the heart lining (endocarditis).
Causes
Q fever is caused by a small germ called Coxiella burnetii. This is found in farm animals such as sheep, cattle and goats. It is passed in the faeces, urine and milk, and is also found in the meat of these animals.
The germ occurs in great numbers in the placenta (afterbirth) of an infected animal. In dry areas, the disease may be contracted by inhaling dust contaminated with dried faeces, urine or afterbirth.
Untreated milk is another source. The disease may also be acquired by the bite of various insects, such as ticks, which are commonly infected.
Diagnosis
Diagnosis is made on the symptoms and carrying out a blood test to look for specific antibodies to C. burnetii in the blood.
Treatment
The antibiotics tetracycline and chloramphenicol are effective against the infection.
Prevention
It is important for people working with farm animals to be aware of the risks of drinking untreated milk and exposure to dust from animal excreta and afterbirth (placentas). Workers in slaughterhouses, rendering plants, dairies and wool-processing plants are also at risk.
The NHS Direct Health Encyclopaedia has been produced for NHS Direct Online by DPP 2000 (a joint venture company of the Doctor Patient Partnership, Radcliffe Medical Press Ltd and Software Production Enterprises Ltd).
The Encyclopaedia has been written by Dr Robert Youngson (author of the Royal Society of Medicine Health Encyclopaedia) and edited by Dr Ian Banks, Dr Vincent Forte, Dr Martin Bell and Rod Cuff.
Content has been reviewed by the NHS Direct Online Editorial Board including medical, nursing, pharmacy, communications and consumer representatives.
The NHS Direct Online Health Encyclopaedia is Crown Copyright.
Biological Warfare Defense Information Sheet
Q Fever
General information:
Q fever is a disease normally found in sheep, cattle, goats and ticks. The cause of the
disease is Coxiella burnetii, a bacteria-like agent known as a rickettsia. Humans acquire
Q fever by inhaling the rickettsia which become airborne during handling and processing of
animals. As an agent of biological warfare (BW), Q fever is an incapacitating agent and
would not be expected to cause significant fatalities. It would likely be distributed as a
cloud of rickettsia that would be inhaled by personnel under attack. Rickettsia are highly
infectious when delivered in this manner. Disinfection of contaminated articles may be
accomplished using a 0.05% hypochlorite solution (1 tbps. bleach per gallon of water).
The military chemical protective mask is effective against inhalation of all Biological
Warfare Agents.
Symptoms:
Symptoms appear about 10-20 days after the Q fever rickettsia are inhaled. The symptoms
resemble flu symptoms and include fever, chills, headache, fatigue and muscle aches. About
one half of persons with symptoms will have pneumonia evident on chest X-ray and some of
these will have a cough or chest pain. The complications of meningitis or and inflammation
of the heart may arise, but these are uncommon. Normally, the duration of Q fever is 2
days to 2 weeks at which time the disease resolves without permanent effects on the
individual.
Medical Countermeasures:
The symptoms of Q fever usually resolve without antibiotic treatment. Antibiotics can
be given to shorten the illness. Tetracyclines are the drugs of choice, some recent work
indicates ciprofloxacin may also be useful. The timing of antibiotic therapy is important.
If given 1-8 days after exposure, the antibiotics will merely delay the symptoms for about
three weeks. Antibiotics begun 8-12 days after exposure and continued for 10 days will
prevent Q fever from occurring.
Q fever is not usually transmitted directly from person to person, so quarantine of
affected individuals is not suggested. Q fever has, however, been transmitted through
blood or bone marrow donations, so health providers should be aware of this possibility.
Source: http://www.emergency.com/qfever.htm
Centers for Disease Control and Prevention
National Center for Infectious Diseases
US Department of Health and Human Services
Q
Fever and Animals
What
is Q fever?

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Q fever is a rickettsial infection caused by Coxiella burnetii (COX-ee-ELL-uh burn-ETT-eye). Only about half the people infected with this organism get sick with Q fever. Most people who get sick start having symptoms 2 to 3 weeks after getting C. burnetii, although symptoms can start sooner. These symptoms include fever, headache, chest or stomach pain, vomiting, and diarrhea. The fever can last 1 to 2 weeks, but many people can also get more serious lung or liver infections as a result of Q fever. |
Organism Responsible for Q fever
Rocky Mountain Laboratories, NIAID, NIH |
Most people get better within 1 to 2 months after being infected. Rarely, people can be sick from Q fever a year or more after getting this disease. For these people, inflammation (swelling) of the heart, especially the valves in the heart, can be a serious problem.
Can animals transmit Q fever to me?
Yes, some animals can pass Q fever to people. Cattle, sheep, and goats are most likely to carry C. burnetii, but other kinds of animals can also have this disease. Most infected animals do not show signs of Q fever, but the organism can be in barnyard dust that contains manure, urine or dried fluids from the births of calves or lambs. People usually get Q fever by breathing in this contaminated barnyard dust. Occasionally, people can get Q fever from drinking contaminated milk or from tick bites.
How can I protect myself from Q fever?
- When possible, avoid contact with the placenta, birth products, fetal membranes, and aborted fetuses of sheep, cattle, and goats.
- Eat and drink only pasteurized milk and milk products.
- If you work around pregnant sheep and goats, get vaccinated (where possible) against C. burnetii infection.
- Quarantine imported animals.
- If you have pre-existing heart valve disease or have had valve replacements, be extra careful around areas with sheep, cattle, and goats.
How can I find out more about Q fever?
Refer to CDC's Web site on Q fever for additional information, including an overview of the disease, diagnosis, and treatment.
Q fever cases in humans is a mandatory reportable disease in most areas. Contact your local, regional or national health department for instructions.
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