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Bartonella and Cat Scratch Disease

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Joel (snowathlete) continues his series on zoonotic pathogens with an introduction to Bartonelliosis

Photo by girlstyle

Bartonella is a zoonotic that frequently infects humans causing diseases termed Bartonelliosis. Probably the most commonly known is cat scratch disease (CSD) which, you guessed it, you catch from cats (especially cute kittens). Cat scratch disease is caused by two species of Bartonella: B. henselae and B. clarridgeiae. But more than a dozen species of Bartonella can cause diseases in humans including B. bacilliformis which causes Carrion’s disease, and B. quintana which causes trench fever. It is not uncommon for people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) to test positive for Bartonella.

Now I have to be honest, I find it hard to take the name ‘cat scratch disease’ seriously. Sure, trench fever sounds pretty rough going, and Carrion’s disease sounds even worse until you realize it was named after Mr Carrion, not decaying flesh, but ‘cat scratch disease’…Seriously?

I thought chronic fatigue syndrome (CFS) was bad. I mean, it sounds so mild, doesn't it? And people get scratched by cats all the time and nothing bad befalls them…Well, often it seems that it is mild, but not always. In addition, there is some evidence that other forms of Bartonellosis are most severe.

Bartonella is an intracellular, rod-shaped bacterium and possesses whip-like flagella. They are Gram-negative, which means that they have a cell wall which is hard to penetrate (it doesn't absorb the dye when a Gram staining protocol is performed) and this means they are more resilient to attack from the immune system or antibiotic treatments. B. henselae for instance, is resistant to penicillin and nafcillin.


Let’s start by looking at how you can get it. As I mentioned already, cats are one of the reservoirs of CSD and humans are often infected via a scratch or bite. Cat fleas are also thought to be a possible route of transmission [1, 2].

Rodents are also reservoirs for the pathogen and ticks have been shown to carry Bartonella as well [3]. Many people infected with other tick-borne infections such as Borrelia or Rickettsia also have Bartonella. Nonetheless, transmission from ticks has not been conclusively proven and some research argues against it [4].

Other species of Bartonella can be transmitted by vectors such as flies in the case of Carrion’s disease and body lice as in the case of trench fever. Transmission of some species of Bartonella from dogs to humans is also thought, by some, to be a possibility, but this is not widely accepted yet.


Infection usually occurs in childhood and is often mild and self-limiting. However, in some cases - especially in those with weakened immune systems - treatment may be required.

In a study in San Francisco, 41 percent of cats were found to be infected with B. henselae [5]. As this was a snap-shot of infection in these cats, and other species of Bartonella were not looked for, it seems reasonable to assume that over the life of a cat, the infection rate of Bartonella may be higher still.


There are many species of Bartonella. B. henselae is the most commonly known and studied, but other species are not well studied and most cannot be tested in mainstream labs. Many are better understood in reference to animals, not just cats but dogs too, and these species may be more damaging to humans than the species that cause CSD [6].


If you were infected via a cat or a cat flea, then it is not uncommon to be infected with toxoplama at the same time. If you got it from a tick then there are a multitude of other infections that you may have received in the deal, including Borrelia (you can read about that here), Babesia, Rickettsia or Ehrlichia. All of these co-infections complicate the picture, making it harder to diagnose and treat, and reducing your chance of recovery. There is evidence suggesting that a concurrent infection with both Bartonella and Borrelia may result in a disease complex which is able to infect and damage the nervous system [7].


Bartonella (Image by AJC1)

In CSD the first signs of infection are papules or pastules at the site of injury, and later swelling of the lymph nodes sometimes occurs near the site of infection. Fever and fatigue, malaise, headache, chills, backache, insomnia, and less commonly weight loss, arthritis, rashes and sore throat may also occur. You may also get marks on the skin that look like – and are often misdiagnosed as - stretch marks.

In more extreme cases you may suffer from encephalopathy (brain dysfunction), neuroretinitis (eye infection) and impaired vision, osteomyelitis (bone infection) or Parinaud oculoglandular syndrome (a granulomatous conjunctivitis) and cardiomyopathy.

As it is thought that some people may be infected with other species of Bartonella that cause non-CSD Bartonellosis, it is possible that symptoms could be different in these cases, and it is also possible to carry the infection (perhaps with resulting immune suppression?) but be asymptomatic.

Can these symptoms be mistaken for ME/CFS? Maybe. It is not uncommon for people diagnosed with ME/CFS to test positive for Bartonella infection and because of the symptom overlap people often suffer with Bartonella for a long time before they are diagnosed with it and treated. It is most likely that it is an opportunistic infection, but there has not been sufficient research carried out to rule it out as a possible cause.


Bartonella invade erythrocytes (red blood cells) and also inhabit the endothelium (the cells forming the interior layer of blood vessels).

There is some evidence that Bartonella hits the immune system, with one paper suggesting that a Bartonella species – B. bacilliformis - is immunosuppressive, and resembles AIDS [8].


It is often hard to diagnose, especially if you weren't injured by a cat or your symptoms occurred sometime after such an event. Some experts believe it is routinely misdiagnosed as another illness. A PCR blood test for the two strains which cause CSD is widely available, but tests for other species are not easy to find. A lymph node biopsy may be performed if you have swollen lymph nodes and an enlarged spleen may be an aid to clinical diagnosis.


Often, Bartonella infection appears to be non-serious and will resolve without treatment, but in established cases where the immune system does not deal with the infection, antibiotics are prescribed and the antibiotic chosen depends on the strains found to cause the infection.

Doxycycline is often used for the species which cause CSD, as is Azithromycin (the treatment of choice in pregnant women), clarithromycin, rifampin, trimethoprim-sulfamethoxazole, or ciprofloxacin may also be given. And there are a multitude of others, depending on the strain and (just as important) who your doctor is.


As already pointed out, there is symptom overlap between the two diseases, some people diagnosed with ME/CFS subsequently test positive for Bartonella, and there are many strains that are not well-known. There is plenty of scope for Bartonella to be a factor in ME/CFS, most likely as a co-infection, but there is also some scope for it to be linked with the pathogenesis of the disease.

The surprising thing is that there has been little published research exploring possible links, which unfortunately means a lot of the evidence for a link is anecdotal. Not insignificant, just not necessarily reliable.

One piece of research shows that some people diagnosed with CFS were found to be positive for various species of Bartonella that they tested for [9] though the proportion of patients in the study with CFS was not large and some of the data in the study is not presented in a way that makes drawing conclusions straightforward.

The only published paper that I could find which looked specifically at ME/CFS and Bartonella was by Komaroff almost 20 years ago [10], which concluded that infection with the henselae strain of Bartonella was unlikely to be the cause of ME/CFS. Welcome, for sure, but hardly sufficient to rule out Bartonella altogether.

Some doctors do test for it, De Meirleir for one certainly tests for it. Others, such as Lerner, Montoya and Cheney, believe that heart problems are common in ME/CFS patients, which may suggest a link to Bartonella as some species are known to cause heart problems, particularly those species which infect dogs.

Are any of these doctors (or anyone else), looking closely at it?

Although there is only one published peer-reviewed paper on Bartonella in ME/CFS, that doesn't mean that people haven't looked. It just means that they didn't find anything worth reporting. But with a lot still unknown about Bartonella species, it is by no means ruled out yet, so we shouldn't be surprised if we hear more about it in the future. In the meantime, as with other zoonotic infections that may present with similar symptomology to ME/CFS (Borrelia, Staphylococcus, Giardia lamblia, etc.), it is well worth being tested for them if you haven't been already, as ME/CFS is of course supposed to be a diagnosis of exclusion.

Joel was diagnosed with ME/CFS in 2009 but struggled with the illness for some time prior to this. He loves to write, and hopes to regain enough health to return to the career he loved and have his work published.

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  1. Higgins JA, et al. 1996. Acquisition of the cat scratch disease agent Bartonella henselae by cat fleas (Siphonaptera:pulicidae). http://www.ncbi.nlm.nih.gov/pubmed/8667399
  2. Foil L, et al. 1998. Experimental infection of domestic cats with Bartonella henselae by inoculation of Ctenocephalides felis. http://www.ncbi.nlm.nih.gov/pubmed/9775583
  3. Martin E Aldelson, et al. 2004. Prevalence of Borrelia burgdorferi, Bartonella spp., Babesia microti, and Anaplasma phagocytophila in Ixodes scapularis Ticks Collected in Northern New Jersey. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC427842/
  4. Telford SR III, et al. 2010. Bartonella spp. transmission by ticks not established. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3322007/
  5. Koehler JE, et al. 1994. Rochalimaea henselae infection. A new zoonosis with the domestic cat as reservoir. http://www.ncbi.nlm.nih.gov/pubmed/8301768/
  6. Edward B, et al. 2010. Bartonellosis: an emerging infectious disease of zoonotic importance to animals and human beings. http://onlinelibrary.wiley.com/doi/10.1111/j.1476-4431.2009.00496.x/abstract
  7. Eskow E, et al. 2001. Concurrent infection of the central nervous system by Borrelia burgdorferi and Bartonella henselae: evidence for a novel tick-borne disease complex. http://www.ncbi.nlm.nih.gov/pubmed/11559306
  8. Eduado Ticona, et al. 2009. The pathophysiology of the acute phase of human bartonellosis resembles AIDS. http://www.medical-hypotheses.com/article/S0306-9877(09)00470-8/abstract
  9. Maggie RG, et al. 2012. Bartonella spp. bacteremia and rheumatic symptoms in patients from Lyme disease-endemic region. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3358077/
  10. Komaroff, et al. 1994. Persistent infection with Bartonella (Rochalimaea) henselae or Afipia felis is unlikely to be a cause of chronic fatigue syndrome.

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I tested positive for lyme, bartonella quintana and bartonella henselae in the past. Now I am negative for all of them. My blood count have always been normal. And my CD57 went up with antibiotic treatment. Now it is normal, but I am still symptomatic, so I go by symptoms. Btw: I am the one who had severe neuropsychiatric symptoms, mainly depression and anxiety, so I think the connection with bartonella is true....

It's a shame that your symptoms have not improved with symptoms.
In Buhner's book, Healing Lyme, he says that Bartonella only accounts for 5% or less of the coinfections in Lyme. He must have thought it was an important issue though since he wrote an entire book about Bartonella.
From Infectolabs Australia site
Bacteria: Bartonella henselae (gram-negative, optional intracellular in endothelial cells / Erythrocytes) and/or BLO = Bartonella like organisms
Vector/Transmission: surface wounds/scratch from cats, Ixodes ricinus
Symptoms: (incubation period 3 – 38 days): headache (80%), fatigue (100%), muscle twitches, tremors, cramps, shivering, fever in the mornings (30%, in thrusts up to 6 weeks, otherwise 1 – 3 weeks), swollen lymph nodes, arthralgia (often), myalgia, insomnia, depression, agitation, amentia, concentration and attention disorder, dizziness, restlessness, gastritis, intestinal problems, sore feet soles (especially in the morning), hypodermic nodules along the extremities, no or minimal joint pain (important according to J.J. Burrascano)
Severe progression: endocarditis, retinitis, epilepsy, aseptic meningitis, hepatosplenomegalia
Risk factors: immune suppression
- PCR on Bartonella in blood (EDTA-blood): direct detection
- Histology (hemangiome/lymphadenitis)
- Antibodies on bartonella henselae-IgM and bartonella henselae-IgG: indirect detection

- Elevated vascular endothelial growth factor (VEGF), only rarely increased
an article on bacteria and the brain etc.

Neurodegenerative diseases are chronic degenerative diseases of the central nervous system (CNS) that cause dementia. For the most part, the causes of these brain diseases remain largely
unknown.1 They are characterized by molecular and genetic changes in nerve cells that result in nerve cell degeneration and ultimately nerve dysfunction and death, resulting in neurological
signs and symptoms and dementia. In addition to neurodegenerative diseases, there are also neurobehavioral diseases that mainly, but not exclusively, appear in the young, such as autistic
spectrum disorders (ASD) that encompass autism, attention deficit disorder, Asperger’s syndrome, and other disorders. There appear to be genetic links to neurodegenerative and
neurobehavioral diseases, but the genetic changes that occur and the changes in gene expression that have been found in these diseases are complex and not directly related to simple genetic alterations. In addition, it is thought that nutritional deficiencies,
environmental toxins, heavy metals, chronic bacterial and viral infections, autoimmune immunological responses, vascular diseases, head trauma and accumulation of fluid in the brain,
changes in neurotransmitter concentrations, among others, are involved in the pathogenesis of various neurodegenerative and neurobehavioral diseases. One of the biochemical changes found in essentially all neurological, neurodegenerative, and neurobehavioral diseases is the overexpression of oxidative free radical compounds (oxidative stress) that cause lipid, protein, and genetic structural changes.

Oxidative stress can be caused by a variety of environmental toxic insults, and when combined with genetic factors, pathogenic processes could result. An attractive hypothesis for the
causation or promotion of neurological disease involves chronic bacterial or viral toxic products, which result in the presence of excess reactive oxygen species and culminate in pathologic
changes. Infectious agents may enter the CNS within infected migratory macrophages, they may gain access by transcytosis across the blood-brain barrier, or enter by intraneuronal transfer from peripheral nerves. Cell-wall-deficient bacteria, principally species
of Chlamydia (Chlamydophila), Borrelia, Brucella (among others), bacteria without cell walls, such as Mycoplasma species, and various viruses are candidate infectious agents that may
play important roles in neurodegenerative and neurobehavoral diseases. Since they are usually systemic, such infections can affect the immune system and other organ systems, resulting in
a variety of systemic signs and symptoms.

Thank you sooo much for this great post! I've been curious about Bartonella for a long time. I was positive for Cat Scratch Disease a couple years after the onset of my chronic illness. Still had the fresh scratch on my arm when I was tested. The infectious disease doctor told me that adults who had not been around cats during their childhood generally got much worse symptoms when infected. I was @ 25 at the time and had just adopted my first-ever cat. A stray, of course. I was actually pretty sick with it, although it was tough to tell what was CSD and what was ME/CFS. One thing I remember is that I was so sore to the touch that it hurt a LOT to take a shower.

I suspect that the CSD was not treated, although I was clearly immune compromised when I got it.

Another interesting twist: I recently took six months of doxycycline for an unrelated infection. During that time, my 33-year sore throat and golf ball glands disappeared. I'd always suspected the sore throat was chronic EBV, but now I'm wondering if it was more likely Bart? Wish I knew more; it seems like the response to doxy is meaningful.

Anyway, thank you thank you for this. I'm going to print it out and take it to my doctor next week.

Loads of good wishes!
it is evident that one can get both bacterial and viral infections at the same time.
it is evident that one can get both bacterial and viral infections at the same time.
I did another posting on this from a research center which specializes in Bartonella and has a wealth of information. They describe the infection as the new epidemic.



One of De Meirleir's latest videos talks about Bartonella. He says that he is finding it a lot in patients (about 50% along with Borrelia and Brucella) and it is hardly ever the strain that causes cat scratch disease (B. Henselae).

Has been treating patients with it for about a year. "Some people recover completely and others recover partially."
What treatment is KDM using for Bartonella?
I don't know if he uses the same with everyone, or not, but for me it's Rifampin and Clarithromycin. I read one paper that showed these two along with Doxy are the three best options.
Hi acer2000,

how long have you take antibiotics?
Do you notice improvements?
I took Zithromax and Rifampin for about 9 months with no improvement in symptoms. I wonder though, if that was the right treatment. I have seen lots of very different treatment protocols for Bartonella.
I took Zithromax and Rifampin for about 9 months with no improvement in symptoms. I wonder though, if that was the right treatment. I have seen lots of very different treatment protocols for Bartonella.
From what I've read (and I haven't completed my research yet) Zithromax (azithromycin) hasnt been proven effective. I wouldnt rule it out yet, but there is better evidence for some other anti-microbials to be used in conjuction with Rifampin - which looks the best one from what ive read so far. Most are not bacteriocidal, and those that are often don't get inside erythrocytes enough, which makes eradication non-simple. I probably would try an alternative if you have solid evidence of infection.
I posted earlier about Buhner saying in his book, Healing Lyme, that bartonella only accounts for 5% of the coinfections. I also mentioned he has a new book specifically devoted to bartonella and mycoplasma.
In the description of the new book, it says bartonella and mycoplasma are the most common coinfections while in Healing Lyme it says babesia accounts for 80% of the coinfections. I'm not sure what's going on, but there is a 7-year gap between the books.
Healing Lyme Disease Coinfections: Complementary and Holistic Treatments for Bartonella and Mycoplasma
Book Description
Release date: May 5, 2013
A guide to the natural treatment of two of the most common and damaging coinfections of Lyme disease--Bartonella and Mycoplasma

• Reveals how these conditions often go undiagnosed, complicate Lyme treatment, and cause a host of symptoms--from arthritis to severe brain dysfunction

• Outlines natural treatments for both infections, with herbs and supplements for specific symptoms and to combat overreactions of the immune system

• Reviews the latest scientific research on Bartonella and Mycoplasma coinfections and how treatment with antibiotics is often ineffective

Each year Harvard researchers estimate there are nearly 250,000 new Lyme disease infections--only 10 percent of which will be accurately diagnosed. One of the largest factors in misdiagnosis of Lyme is the presence of other tick-borne infections, which mask or aggravate the symptoms of Lyme disease as well as complicate treatment. Two of the most common and damaging Lyme coinfections are Bartonella and Mycoplasma. Nearly 35 million people in the United States are asymptomatically infected with each of these pathogens, and at least 10 percent will become symptomatic every year--with symptoms ranging from arthritis to severe brain dysfunction.

Distilling hundreds of peer-reviewed journal articles on the latest scientific research on Bartonella, Mycoplasma, and Lyme disease, Stephen Buhner examines the complex synergy between these infections and reveals how all three can go undiagnosed or resurface after antibiotic treatment. He explains how these coinfections create cytokine cascades in the body--essentially sending the immune system into an overblown, uncontrolled response in much the same way that rheumatoid arthritis or cancer can. Detailing effective natural holistic methods centered on herbs and supplements, such as the systemic antibacterial herb Sida acuta, which acts to protect blood cells from invading organisms, he reveals how to treat specific symptoms, interrupt the cytokine cascades, and bring the immune system back into balance as well as complement ongoing Lyme disease treatments.
I posted earlier about Buhner saying in his book, Healing Lyme, that bartonella only accounts for 5% of the coinfections. I also mentioned he has a new book specifically devoted to bartonella and mycoplasma.
In the description of the new book, it says bartonella and mycoplasma are the most common coinfections while in Healing Lyme it says babesia accounts for 80% of the coinfections. I'm not sure what's going on, but there is a 7-year gap between the books.
Interesting. I guess maybe it's new strains having been found in the intervening years, and better testing techniques, that account for the change?
Interesting. I guess maybe it's new strains having been found in the intervening years, and better testing techniques, that account for the change?
It's very strange that such a change in statistics could happen over an 8-9 year gap, but your guess is as good as mine. I guess someone will have to read the book...:D
It's very strange that such a change in statistics could happen over an 8-9 year gap, but your guess is as good as mine. I guess someone will have to read the book...:D

The standard tests for Bart don't test for many strains--2 or 3 I think. Newer tests check for many more.

Buhner posted this December 2012. I guess he's publishing a separate book for coinfections babesia and ehrlichia (which he said were the most common in his Healing Lyme book published around 2005).
Dear Stephen,
I want to order your revised book on lyme. When will it be available for purchase?

Stephen’s response:
My writing work has taken unexpected turns. My publisher asked me to update the Herbal Antibiotics book, which came out last summer, and was a major undertaking. Then I began to update the lyme book, starting with coinfections, but that turned into a major project which is now a book on mycoplasma and bartonella coming out May 2013 from Inner Traditions. Then the publisher of Herbal Antibiotics wanted an herbal antiviral book, which turned out to be a massive undertaking, and is coming out in August of 2013, and now I am still having to do my originally planned project Gaia’s Mind for which I already signed a contract. The next book after will be on babesia, anaplasma and ehrlichia, and then and only then will I have time to do the lyme book revisions, so we are looking at spring 2015 for a release date since I will be on the road teaching much of 2013 and will only be able to write in 2014.
He also posted this March 2013 about length of treatment for bartonella
Dear Stephen,
You say that the bartonella protocol should be used for 30 days. If I still have bartonella symptoms after 30 days should I stop the protocol or continue longer?

Stephen’s response:
If you are feeling better, that is, if the protocol seems to be working, but the symptoms come back when you stop, then the protocol should be modified and continued. The point is to get rid of the blood cell infection. If it comes back then the dosage was probably not high enough.