What is Trench Fever?
During the outbreak of COVID-19 in 2020, there was a rise of a disease known as trench fever in Denver, Colorado. This was a reminder that we should always be prepared for different health threats, whether they are new or have occurred before. Trench fever, historically, was a disease that affected over a million soldiers during World War I and is commonly associated with people experiencing homelessness and poor hygiene. Typically, symptoms of trench fever include recurring fever, which is often referred to as “quintan fever,” and other common flu-like symptoms such as fever, headache, tiredness, and rashes.
What Causes Trench Fever?
Trench fever is caused by a specific type of bacteria called Bartonella quintana. This disease is believed to originally come from animals. However, it now mainly passes to humans through three types of lice: the body louse, the head louse, and the pubic louse. The most common way to get trench fever is through the body louse.
There have been some reports suggesting that bed bugs and cat fleas might also be able to spread trench fever. Usually, the disease is passed on when lice or possibly bed bugs, or fleas, leave behind waste that is contaminated with the Bartonella quintana bacteria.
Risk Factors and Frequency for Trench Fever
The disease now known as trench fever was first recognized as a distinct condition separate from diseases like typhoid and dengue in 1915. However, researchers weren’t initially sure if it was caused by bacteria or another type of microorganism, known as protozoa. The connection to bacteria became clearer when it was noticed that lice that feasted on trench fever patients were full of rickettsial bodies. Further proof came when it was established that these lice excreted a specific type of bacteria when feeding on people with the disease. Things became even clearer when it was observed that directly injecting these bacteria into volunteers made them more infectious. The bacteria were successfully grown in a laboratory in 1961, which opened doors to the use of specific antibiotics for treatment. Initially classed as Rickettsia quintana, the disease-causing bacteria have since been renamed to Bartonella quintana.
During the first World War, trench fever was a major problem causing illness and death amongst over a million soldiers. The disease made a comeback during the second World War, but it wasn’t as deadly as during the first. Post World War II, the disease surfaced in multiple outbreaks around the world, including in Ethiopia, Poland, Mexico, USSR and Tunisia. From the 1990s onwards, trench fever has mostly been seen in small, isolated outbreaks. These modern outbreaks often mimic other diseases that affect the blood, heart, and blood vessels. As recently as 2020, an outbreak in Denver, Colorado affected many homeless persons.
Signs and Symptoms of Trench Fever
The severity of this disease ranges from mild flu-like symptoms to a more serious condition that could drain your energy. The symptoms usually appear about seven days after you’ve been exposed to the disease. Fever is a main symptom and it can show up in four different ways. Most commonly, patients experience patterns of fever that come and go, much like malaria. These patterns include:
- A single fever episode
- Fever episodes lasting four to five days
- Three to five rounds of fever lasting five days each, with symptom-free periods in between
- Continuous fever lasting two to six weeks
The term “quintan fever” comes from the repeating five-day fever episodes. This is also reflected in the name of the bacteria that causes the disease, B. quintana. Other symptoms of this disease are similar to those of the flu and can include feeling weak, headaches, dizziness, bone pain (especially in the shins), nausea, vomiting, and weight loss.
During a physical examination, the doctor may find that the patient has a fever with a temperature above 38.4 °C (101.1 °F), an enlarged spleen that can be felt, and a rash that usually appears on the torso.
Testing for Trench Fever
Bartonella quintana, a type of bacteria, can be hard to identify because it grows very slowly. If doctors suspect you might be infected with this type of bacteria, they use different types of tests.
One of the tests used is called a culture. In this test, a sample is taken from your body and placed in special conditions to help the bacteria grow. The bacteria is then identified under a microscope. However, because Bartonella quintana is slow-growing, the sample has to be kept under specific conditions (35 degrees Celsius and 5% carbon dioxide) for a minimum of 21 days. Even then, there might not be enough bacteria to identify.
To overcome this limitation, doctors often turn to another test called Polymerase Chain Reaction (PCR). This test can identify Bartonella’s genetic material in your body, which is a quicker and more reliable way of diagnoses.
One other diagnostic method involved is known as Serology. In serology, your blood sample is examined for the presence of antibodies – proteins your body makes to fight off infections. If antibodies against Bartonella quintana are found, it indicates that you are or were infected with the bacteria. This test can also tell us whether the infection is new or old based on the number of antibodies found. This test is particularly effective in cases involving infections of the heart, known as endocarditis.
Treatment Options for Trench Fever
The best way to handle trench fever and other infections caused by Bartonella quintana isn’t set in stone, because there isn’t a lot of published research on it. The treatment that doctors recommend depends on the patient’s symptoms and other health conditions they may have.
For acute or chronic infections where the condition hasn’t affected the heart (a situation known as endocarditis), doctors find oral doxycycline to be effective. Doxycycline can typically be taken once a day for four weeks. Sometimes, it’s combines with an antibiotic called gentamicin, which is given intravenously (through a vein) once a day for two weeks at the start of the treatment. If the patient can’t or shouldn’t take gentamicin for various reasons (like unable to access the medication, allergies, or other health concerns), another antibiotic called rifampin can be a good substitute during the first two weeks of treatment.
There was a study conducted by Foucault et al., in which they found that combination therapy (using both antibiotics) was successful in getting rid of the infection in all seven patients they treated. In comparison, only two out of nine patients who received no treatment successfully got rid of the infection.
For those taking gentamicin, it’s important to monitor levels closely, especially if the patient has kidney issues. Also, patients with long-term trench fever should have their heart checked with an echocardiogram, as this could indicate endocarditis that may need more extensive antibiotic treatment.
What else can Trench Fever be?
Malaria is a disease caused by a parasite carried by female Anopheles mosquitoes. It can cause repeated fever episodes and symptoms similar to trench fever like headaches, fatigue, stomach upset, and muscle pain. Severe cases can lead to yellowing of skin (jaundice), confusion, seizures, and dark urine. The most reliable way to diagnose Malaria is by examining a sample of blood under a microscope.
Typhus is caused by Rickettsia prowazekii and Rickettsia typhi. It can cause a range of symptoms including fever, chills, muscle aches, and a skin rash.
Relapsing Fever causes repeated episodes of fever, chills, and a general feeling of being unwell. The culprit behind this disease is a spiraling-shaped bacteria, Borrelia recurrentis. Diagnosing this disease may involve blood tests or genetic testing (PCR).
Leptospirosis can present in two forms. The milder form can cause symptoms similar to trench fever, like headaches, coughs, a non-itchy rash, fevers, rigors, muscle pain, loss of appetite, and diarrhea. A more severe form of this disease, known as Weil disease, may cause kidney failure, yellowing of skin (jaundice), bleeding, and trouble breathing. Specialized culture tests or a microscopic agglutination test can help diagnose this disease.
Rocky Mountain Spotted Fever (RMSF) initially presents with fever, headaches, and a rash, which can either have red spots (petechiae) or a rash of small bumps and spots (maculopapular rash). Distinct from trench fever, the rash often spreads from the extremities to the trunk. Other symptoms include swollen lymph nodes and changes in the nervous system, most notably confusion or neck stiffness, muscle and joint pains, liver inflammation (hepatitis), stomach upset, and cardiovascular instability. The diagnosis is usually done by testing for the presence of specific immune proteins called Immunoglobulin M (IgM) and Immunoglobulin G (IgG).
What to expect with Trench Fever
Trench fever isn’t widely documented, but it shows low overall death rates. Some patients may not need treatment as the infection could resolve itself. However, there has been an increase in observed cases of bacteremia, which is bacteria in the blood, this has led to a stronger recommendation to treat the disease.
The outcome can vary depending on a patient’s immune system status. More severe cases with serious complications and poorer outcomes are seen in patients with conditions that weaken the immune system. These conditions include the Human Immunodeficiency Virus (HIV), patients who have received organ transplants and are on drugs that suppress the immune system, and alcoholism.
Possible Complications When Diagnosed with Trench Fever
Bartonella quintana, a type of bacteria, can cause serious heart valve infection, or endocarditis, in people who have been infected for a long time. This bacteria can also cause blood vessel growth clusters, a condition known as bacillary angiomatosis, mostly in individuals with weakened immune systems. Symptoms of people with endocarditis usually include chest pain, difficulty in breathing, weight loss, night sweats, and several non-specific signs like feeling unwell, coughing, and tiredness.
Typically, medical examinations can detect endocarditis through certain signs such as new heart murmurs, red or purple skin spots (Janeway lesions), painful red bumps under the skin (Osler nodes), and particular blood vessel or immune responses.
Several organisms, including Bartonella, are commonly linked to endocarditis despite not appearing in blood cultures. Other organisms include Coxiella, Chlamydia, Legionella, Mycoplasma, Aspergillus, and Brucella. It’s incredibly important to test for these pathogens.
Notably, a study in France by Fournier et al. found that Bartonella was the cause of about 20% of endocarditis cases where blood cultures did not identify any organisms.
Moreover, not every person with trench fever, an illness caused by Bartonella, develops bacillary angiomatosis. However, it is something to consider for patients with weakened immune systems, like people living with HIV or those receiving transplants and immunosuppressive therapy. When Bartonella quintana accumulates in large amounts in a host with a weak immune system, it can lead to the growth of new blood vessels forming benign tumors. These organisms have a tendency to clump together, according to Chiraviglio et al., as they produce sticky surfaces.
Preventing Trench Fever
It’s important to talk about the side effects of certain medications, like doxycycline, with patients. One such side effect is photosensitivity, which can make your skin more sensitive to sunlight. This means you may need to avoid staying in the sun for too long and should wear sun-protective clothing. It’s also crucial to keep your surroundings clean to stop the spread of any potential infections.
