What is Coxiella burnetii Infection (Q Fever)?
Coxiella burnetii is the bacteria responsible for Q fever. This fever typically affects individuals who interact closely with farm animals, making it a disease mainly linked to the animal industry. Most people who contract Q fever show no symptoms, but others can develop a fever-like illness. Fortunately, there are effective treatments and vaccines available. Conversely, without suitable treatment, it can evolve into a long-term infection that affects various body organs, including the heart, bones, and lungs. Therefore, it’s essential that individuals working in the animal industry be aware of their risk of getting this disease and take preventive measures.
What Causes Coxiella burnetii Infection (Q Fever)?
Coxiella burnetii is a type of bacteria that lives inside cells and can change its form. This can cause Q fever, a disease that can infect both humans and animals. The bacteria exist in two phases; in phase I, it lives in animals where it is highly infectious. In phase II, it’s not usually infectious and can survive in cells or fertilized eggs.
Risk Factors and Frequency for Coxiella burnetii Infection (Q Fever)
C. burnetii, a bacteria responsible for Q fever, can be found all over the world, except for New Zealand. Given its easy spread through the air and its resistance to environmental conditions, it could potentially be used as a biological weapon. People usually get infected by breathing in airborne particles from animals like cows, goats, and sheep, or their products. However, ticks are the main carriers of this bacteria. Besides, Q fever can also occur through exposure to manure from sheep or goats, wild animals, and pets such as cats and dogs. Although rare, occasionally people can get this infection through a blood transfusion or from coming into contact with a woman who has the infection during childbirth.
Signs and Symptoms of Coxiella burnetii Infection (Q Fever)
Q fever is a disease that is usually diagnosed when a person has been exposed to animals that have recently given birth, which is a significant risk factor. It takes between 2 and 6 weeks for symptoms to appear after exposure.
The symptoms of Q fever vary widely. Some people may not experience any symptoms, while others may have severe symptoms. The symptoms one experiences can depend on how the disease was contracted and the volume of bacteria they were exposed to. Reported symptoms have included pneumonia and liver inflammation from exposure through the lungs and abdomen, respectively. Heart inflammation has also been linked to exposure to large amounts of bacteria.
Common symptoms typically include fever, headache, muscle pain, joint pain, and cough. Some people may develop a type of pneumonia that doesn’t present typical symptoms but does show up on chest X-rays.
- Febrile illness: Fever, often accompanied by a headache, is the most common symptom. It usually peaks within 2 to 4 days and subsides within 5 to 14 days. However, it can last longer in untreated or elderly patients.
- Atypical pneumonia: Characterized by a dry cough, fever, and unusual chest X-ray results.
- Hepatitis: Symptoms can include fever, abdominal pain (especially in the upper right area), nausea, vomiting, diarrhea, and loss of appetite.
Cardiac problems like heart inflammation and pericarditis can occur in some patients with Q fever. This can potentially be fatal. Rarely, patients may also develop a pink rash on the trunk. Some patients may also experience neurological symptoms due to Q fever, such as encephalitis, meningitis, or peripheral neuropathy.
Testing for Coxiella burnetii Infection (Q Fever)
Working with C. burnetii, a specific type of bacteria, in a lab can be risky. This is due to the fact that it has caused infections in lab workers in the past. Therefore, it should only be handled in high-security labs known as ‘biosafety level 3 laboratories’. There are various ways to identify this bacteria. A common method involves studying the body’s immune response to it. However, the key tool used by scientists involves a technique called indirect immunofluorescence, which is sensitive and accurate.
In patients with a recent Q fever infection – a disease caused by C. burnetii – typical lab results may show a normal white blood cell count (in about 90% of patients), a reduced platelet count (25%), elevated liver enzyme levels (70%), the presence of particular types of autoantibodies (65%), and antibodies against a specific enzyme called phospholipase (50%). For patients with long-term or ‘chronic’ Q fever, lab findings may show either an increased (25%) or decreased (15%) white blood cell count, increased liver enzyme levels (40%-60%), a reduced platelet count (26%-50%), anemia (40%), increased levels of a waste product called creatinine (65%), the presence of specific autoantibodies (40%), immune complexes (90%), antibodies that target components of cells’ nuclei (35%), and a factor related to rheumatoid arthritis (60%).
Treatment Options for Coxiella burnetii Infection (Q Fever)
If a person shows symptoms or is pregnant and doesn’t show any symptoms, they should receive treatment for acute Q fever. It’s ideal if treatment starts within three days of the symptoms appearing.
The following treatments are suggested for acute Q fever:
* Children: a 10 to 14 day course of Doxycycline at 100mg per day, or a treatment of trimethoprim-sulfamethoxazole (TMP-SMX) at 8 to 12 mg per kg each day.
* Adults: a 14 day course of Doxycycline at 100mg per day (preferred); other options include fluoroquinolones, minocycline, or TMP-SMX.
* Pregnant women: a treatment of TMP-SMX ranging from 320mg to 1600mg until the 7th month of pregnancy has ended.
Fluoroquinolones are recommended for Q fever that has spread to the brain and spinal cord, as these can penetrate these areas. For chronic Q fever, doxycycline combined with hydroxychloroquine is given for a minimum of 18 months.
Vaccines against Q fever are available for people and animals. For humans, a vaccine is available that has been made inactive with formaldehyde. For animals, a vaccine is available which has been extracted with chloroform-methanol. Only people who haven’t developed immunity through previous exposure should get the vaccine to avoid serious local reactions.
What else can Coxiella burnetii Infection (Q Fever) be?
Q fever is a disease that can present in many different ways, making it tricky to diagnose. During diagnosis, it’s important to rule out other conditions that show similar symptoms. These could include:
- Hepatitis (liver disease often caused by a virus)
- Pneumonia (a type of lung infection) caused by pneumococcus or atypical organisms
- Meningococcal meningitis (a serious infection of the thin lining that surrounds the brain and spinal cord)
- Lyme disease (a tick-borne illness)
- Rocky Mountain spotted fever (a bacterial disease spread through the bite of an infected tick)
- Brucellosis (a bacterial infection that can affect a variety of animals and can also be passed on to humans)
- Leptospirosis (a bacterial infection that humans can get from animals)
All these possible conditions must be taken into consideration and appropriate medical tests conducted to ensure the correct diagnosis is made.
What to expect with Coxiella burnetii Infection (Q Fever)
Effective and timely treatment for Q fever often results in excellent outcomes. Thanks to improvements in detection and treatment methods, the mortality rate for chronic Q fever has now fallen to less than 5%. However, without treatment, the outlook for these patients tends not to be favorable.
Possible Complications When Diagnosed with Coxiella burnetii Infection (Q Fever)
If acute Q fever isn’t treated properly, it can turn into chronic Q fever. This change can happen anywhere from months to years after the first infection. Chronic Q fever can show up in different ways, such as endocarditis (an infection on the inner lining of your heart chambers and heart valves) in about 75% of cases, osteomyelitis (a bone infection), vascular infection (an infection of the blood vessels), aortic graft infection (an infection of an aortic graft, which is a graft of blood vessels), chronic hepatitis (inflammation of the liver), especially in patients who abuse alcohol, and pseudotumors (non-cancerous growths) in the spleen and lungs. People who get chronic infections often already have other health conditions like heart valve lesions, vascular abnormalities, and a weak immune system.
If a woman contracts Q fever while she’s pregnant, it can increase risks for both the mother and the baby. Pregnancy complications caused by Q fever can include premature birth, miscarriage, slowed fetal growth, or stillbirth. It is still not known exactly how the infection affects the fetus when it is passed from the mother through the placenta.
Common Manifestations of Chronic Q Fever:
- Bacterial culture-negative endocarditis
- Osteomyelitis
- Vascular infection
- Aortic graft infection
- Chronic hepatitis in patients with alcoholism
- Pseudotumors of the spleen and lungs
Pregnancy Risks Related to Q Fever:
- Premature delivery
- Spontaneous abortion or miscarriage
- Intrauterine fetal growth restriction
- Intrauterine fetal death
Preventing Coxiella burnetii Infection (Q Fever)
Before spreading manure on fields, it should be treated with lime or a 0.4% solution of calcium cyanide. This helps to make it safe and to protect the plants and soil from any harmful substances.
Any infected materials, which can include the fluids and membranes from a birth, the placenta, any unborn animals that have been miscarried, and bedding that has been contaminated, should be disposed of properly. This usually involves incinerating (burning) them and then burying the remains safely.
It’s important to control ticks, which can spread diseases. This tends to involve maintaining good cleanliness standards and using specific strategies to keep ticks away.
You shouldn’t consume milk and milk products unless they’ve been pasteurized first. Pasteurization is a process that kills harmful bacteria, making the milk safe to drink.
The best way to avoid getting infected is to stay away from animals that are carrying the infection.
People should be made aware of the long-term issues that can arise if the condition isn’t treated properly. This helps them understand the seriousness of following their treatment plan.
Patients should be reassured that Q fever can be treated effectively with the right medications. This can help to ease their worries about their condition.
Those working in the animal industry should be made aware of the risk factors for catching Q fever. This can help them take precautions to protect themselves.
If any animals in a group are found to be infected, they should be separated from the rest. Any new animals that are brought in should also be kept separate for a certain period to ensure they’re not carrying any diseases.
Before bringing any animals into research labs, they should be tested first to ensure they’re not carrying any diseases. This protects both the other animals and the people working in the lab.
