Q fever is a worldwide zoonosis that has been considered an underreported and underdiagnosed illness because symptoms frequently are nonspecific.
The causative organism, Coxiella burnetii, naturally infects some animals, such as goats, sheep and cattle, but infected animals may appear healthy. C. burnetii bacteria are found in the birth products (i.e. placenta, amniotic fluid), urine, feces, and milk of infected animals. People can get infected by breathing in dust that has been contaminated by infected animal feces, urine, milk, and birth products. People who help animals give birth, such as farmers and veterinarians, have a higher chance of getting Q fever.
Figure: Q fever cases in Taiwan, 2008-2022.
Q Fever Surveillance in Taiwan
- Taiwan National Infectious Disease Statistics System–Q Fever
- Self–reporting through toll–free 1922 hotline or local public health authority.
Prevention and Control
- Animals spread the germ when they give birth. Reduce risk of getting Q fever by avoiding contact with animals, especially animals in labor.
- Do not consume non–pasteurized milk and milk products.
- Certain professions are at increased risk for exposure to C. burnetii, including veterinarians, meat processing plant workers, sheep and dairy workers, livestock farmers, and researchers at facilities housing sheep and goats. People working in these areas may need to take extra precautions.
- Q fever vaccines are not available in Taiwan. The licensed vaccine for humans is only commercially available in Australia. It should be noted that vaccination during the incubation period of a natural attack of Q fever does not prevent the development of the disease. The Q fever vaccine and skin test are available in Australia and users pay for it.
- How is the Q fever transmitted?
Infection in humans usually occurs by inhalation of bacteria from air that is contaminated by the excreta of infected animals. Other modes of transmission to humans, including ingestion of unpasteurized milk or dairy products, and human–to–human transmission, are rare.
- What are the clinical symptoms of Q fever?
Q fever has acute and chronic stages and can cause mild or severe symptoms.
Acute Q fever symptoms in humans vary, the condition typically is characterized by a nonspecific febrile illness. People who develop severe cases may develop inflammation of the lungs (pneumonia) or liver (hepatitis). And symptomatic patients might be ill for weeks or months if untreated.
A very small percentage of people who become infected with Q fever develop a more serious infection called chronic Q fever. Chronic Q fever is serious and can be fatal if not treated correctly. Infection with chronic Q fever requires months of antibiotic treatment. Chronic Q fever is more likely to occur in people with heart valve disease, blood vessel abnormalities, or who are immunosuppressed. Women infected during pregnancy may also be at risk. People with chronic Q fever usually develop an infection of one or more heart valves (called endocarditis).
- What are the treatments for Q fever?
Most cases of acute Q fever will recover without antibiotic treatment. Those that do require treatment can be effectively treated with the antibiotic doxycycline.
Chronic Q fever is a serious infection and requires several months of antibiotic treatment. Chronic Q fever is treated with a combination of antibiotics including doxycycline and hydroxychloroquine for several months.
- WHO|Report of WHO Workshop on Q Fever
- USA CDC|Q Fever