Bartonellosis
Bacterial infections
Many possible symptoms
May resemble other diseases
Unreliable tests and often inappropriate treatments
No vaccination possible
Can become chronic
Sections of the page:
THE INFECTION
What are bartonellosis ?
Bartonellosis is an infectious disease caused by various bacteria of the genus Bartonella . Historically, it has been classified into several distinct diseases depending on the symptoms and the species of Bartonella involved [ 1 ].
The three best known are:
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Cat scratch disease , caused by Bartonella henselae
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Trench fever , caused by Bartonella quintana
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Carrion's disease , caused by Bartonella bacilliformis
To date, more than 36 different species of Bartonella have been discovered. About half of them can cause human diseases, presenting similar symptoms [ 2 ]. Therefore, this classification (one disease per species) is currently losing its meaning and the simple term bartonellosis seems more appropriate to name these diseases.
Furthermore, it appears that several species can coexist in a patient (such as B. henselae and B. vinsonii), which can lead to worsening of symptoms and increase the risk of developing a more severe disease [ 17 ].
Like Lyme borreliosis and babesiosis, bartonellosis can be difficult to diagnose and extremely disabling , sometimes leading to serious neurological and psychiatric presentations [ 1 - 3 ].
A common infection :
Bartonella is one of several infectious pathogens that frequently co-occur in patients, along with other agents such as Borrelia and Babesia [ 4 - 5 - 6 ]. This is referred to as "co-infections" or "co-infected person" . Often, it is the combination of these pathogens in the same individual, combined with a complex immune response to their simultaneous presence, that causes severe and disabling chronic symptoms [ 7 - 8 ].
How are they transmitted ?
Bartonella species are transmitted in various ways by many animals:
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mammals : cats, dogs, rabbits, etc.
-
insects : fleas, bedbugs, body lice, horseflies, blood-sucking flies, etc.
-
arachnids : ticks, spiders, etc.
Mammals transmit these bacteria to humans through scratches, bites, or licking an open wound. For many insects and arachnids, transmission occurs through bites or indirect contamination via their feces [ 2 - 9 - 10 ].
The many pathogenic Bartonella species (more than 20) have reservoirs and vectors that vary depending on their species. The table below provides a brief summary for some species:
B. henselae
Cats, humans, dogs, horses
Fleas, lice, cats (scratches), ticks
B. quintana
Humans, cats, dogs
Body lice, fleas, bedbugs
B. bacilliformis
Humans
Sand flies, fleas
B. elizabethae
Rats, dogs, humans
Chips
B. vinsonii ssp. berkhoffi
Dogs, horses, humans
Fleas, bites (dogs), ticks,
B. clarridgeiae
Cats, dogs
Bites, scratches, fleas, ticks
B. alsatica
Rabbits, humans
Scratches, fleas, ticks
B. rochalimae
Dogs, humans
Fleas, ticks
B. koehlerae
Cats, dogs, humans
Chips
B. grahamii
Mice, humans
Chips
B. washoensis
Squirrels
Fleas, ticks
+ 12 other species
...
...
Reservoir
Vectors
Species
What is the prevalence in Switzerland ?
Although Bartonella infections are common, there are no studies on the prevalence in humans. However, publications have shown that approximately 8 to 12% of cats are affected by Bartonella henselae in Switzerland, and that 15.3% of cats and 3.6% of dogs are infected on average worldwide [ 11 - 12 ].
In Switzerland, nearly 1.8 million cats and 500,000 dogs coexist with humans, thus constituting a significant potential source of contamination for Bartonella .
Finally, up to 40% of ticks carry Bartonella henselae in Europe [ 13 ].
Bartonellosis
Bacterial infections
Many possible symptoms
May resemble other diseases
Unreliable tests
Treatments often inappropriate
Can become chronic