Trench fever re-emergence in the ‘urban jungle’

Bartonella quintana, a gram-negative bacterium, was first identified as an important human pathogen during World War I, causing an epidemic of louse-borne trench fever among 1 million troops across Europe. Trench fever was described with non-specific, highly variable clinical manifestations such as malaise, fever, headache, and bone and body pain, especially severe in the shins.

Body lice (Pediculus humanus corporis), are the vectors of B. quintana to humans. Body lice are small (less than 1 mm), oval white, cream, pink or black insects. Body lice live and lay nits (eggs) in clothing and come to the skin only to feed on human blood. B. quintana is transmitted when an infected louse excretes B. quintana onto the host’s skin and the excretion is then scratched or rubbed into the skin or open membranes.

Re-emergence of opportunistic pathogen

In recent years, the re-emergence of this opportunistic pathogen has occurred on all continents, except Australia and Antarctica. Interest in the disease has increased due to outbreaks predominantly in homeless populations in Seattle and San Francisco in the US, and in Marseille, France.

Prevalence of B. quintana DNA in body lice from homeless people has been reported as 33.3% in San Francisco; 16.7% in Japan; 12.3% in Russia; and 20% in France. Some patients develop “classic trench fever symptoms,” such as headache, mild fever, bone pain (mainly in the shins) and neck and back pain, where as other clinical symptoms include relapsing febrile illness, bacteremia, endocarditis, lymphadenopathy and bacillary angiomatosis in the liver (bacillary peliosis), spleen, bone marrow, lymph nodes and, most commonly, the skin.

Homeless population

Several factors in the homeless population, such as crowded and unsanitary living conditions, inability to change clothes regularly and close exposure to people potentially carrying ectoparasites, predispose homeless people to louse infestations. Alcoholism, malnutrition and coexisting health problems such as HIV infection contribute to an altered immunity, thus increasing susceptibility to B. quintana infections.

Due to the broad range of symptoms, B. quintana infection may be unrecognized and, thus, go untreated. In those from at-risk populations, such as homeless people, the following conditions may require further investigation for B. quintana: endocarditis, lesions compatible with bacillary angiomatosis and relapsing febrile illness with prominent bone pain in the legs.

Diagnosis, treatment

The most widely used method to diagnose B. quintana infection is serological testing, using indirect immunofluorescence or western blot. Other methods of diagnosis are not readily available, including culturing of tissue or blood. Detection of

B. quintana in tissue such as heart valve and bacillary angiomatosis tissue can be achieved using polymerase chain reaction or immunohistochemistry at the CDC and in a few commercial laboratories.

Treatment recommendations include:

• Chronic bacteremia-daily oral doxycycline for 28 days, in combination with gentamicin IV for first 14 days;
• Endocarditis–doxycycline IV or orally for 6 weeks, in combination with IV gentamicin once-daily, for 14 days, with close monitoring for valve replacement;
• Bacillary angiomatosis-erythromycin or doxycycline for a minimum of 3 months.

It is important to note that body lice live in the clothing of infested people and only go to the body to feed. If an infested person can be given a complete change of clothes and showered, the body lice infestation will cease. Since it is not always possible to have homeless people change their clothing and bedding regularly, eradication of major louse infestations is dependent on washing and drying sheets on the hot cycle at homeless shelters.

For more information on bacillary angiomatosis and treatment of Bartonella infections in immunocompromised patients, please read: HIV and Bartonella: Bacillary Angiomatosis and Peliosis at www.hivinsite.ucsf.edu/InSite?page=kb-05-01-03.

For more information about body lice, please visit the California Department of Public Health website: www.cdph.ca.gov/HealthInfo/discond/Pages/BodyLice.aspx.

For more information:

• Bonilla DL. Emerg Infect Dis. 2009;15: 912-915.
• Brouqui P. N Engl J Med. 1999;340:184-189.
• Foucault C. Clin Infect Dis. 2002;35: 489-684.
• Foucault C. Emerg Infect Dis. 2006;12:217-223.
• Jackson LA. Emerg Infect Dis. 1996;2:141-144.
• Jackson LA. J Infect Dis.1996;173:1023-1026.
• Koehler, JE. N Engl J Med.1997;337:1876-1883.
• Ohl ME. Clin Infect Dis. 2000;31:131-135.
• Rydkina EB. Emerg Infect Dis. 1999;5:176-178.
• Sasaki T. J Med Entomol. 2002;39:427-429.
• Vinson JW. Am J Trop Med Hyg.1969;18:713-722.

Denise Bonilla is a senior public health biologist in the Vector-Borne Disease Section of the Infectious Disease Branch of the California Department of Public Health. She routinely manages the California tick-borne disease program, but specializes in the ectoparasites of urban populations such as body and head lice, scabies and bed bugs. Anne Kjemtrup, DVM, MPVM, PhD, is a research scientist III in the Vector-Borne Disease Section at the California Department of Public Health. Jane E. Koehler, MA, MD, is a professor of medicine in the division of infectious diseases at the University of California-San Francisco. Vicki Kramer, PhD, is a chief of the Vector-Borne Disease Section at the California Department of Public Health. Mary Joyce Pakingan is a laboratory assistant in the Vector-Borne Disease Section at the California Department of Public Health. Disclosures: The researchers report no relevant financial disclosures.