|
|||||||||||||||||
|
|
EID Home | Ahead of Print | Past Issues | EID Search | Contact Us | Announcements | Suggested Citation | Submit Manuscript |
|
Dispatch Tularemia Outbreak, Bulgaria, 1997–2005Todor Kantardjiev,*
Ivan Ivanov,* Tzvetan Velinov,* Plamen Padeshki,* Boris Popov,* Roumiana
Nenova,* and Milcho Mincheff† Microbiologic and Epidemiologic Approaches for Investigation of OutbreakEpidemiologyAfter the 1962 outbreak, annual active epidemiologic surveillance was carried out through a plan worked out by the public health authorities and included the following: 1) bacteriologic examination of trapped and dead rodents, 2) bacteriologic examination of water samples, and 3) serologic examination of patients with unexplainable enlarged lymph nodes. A total of 285 patients had tularemia from 1997 to 2005. All patients were initially interviewed by a primary care physician, who sent the patients to the Hospital for Infectious Diseases (upon tularemia indication) and the results to the Regional Epidemiology Center. The S1 serum samples were collected immediately after clinical indication (1–4 weeks after the onset of symptoms) and the S2 (convalescent-phase) serum samples were collected 15 ±2 days after the S1. S3 samples were collected 3 months ±15 days after the end of therapy. The epidemiologic survey included the following information: address, onset of disease, place of work and possible contact with animals, presence of dust at the work place, water and food sources, hunting or consumption of game, and history of tick bite. Questionnaires filled out by the patients show that they did not drink water from the contaminated wells. The water, however, was used for irrigating backyard vegetable gardens, and those vegetables were eaten. Since the human isolates are closely related to isolates recovered from well water and less to isolates from hares and ticks, we consider the alimentary route from food by contaminated rodents or water as the principal one. Culture MethodsFive hundred milliliters of water were collected in a sterile container. All subsequent steps were carried out in a class III biosafety cabinet. The water was centrifuged at 5,000 × g for 10 min. The pellet was dissolved in 1.5 mL sterile phosphate-buffered saline (PBS) and centrifuged again as above. The pellet was again dissolved in 1.5 mL PBS. One third (0.5 mL) was cultured on modified Thayer-Martin agar. Guinea pigs were passed intraperitoneally with another 0.5 mL, and the remaining 0.5 mL was kept at –70°C. Guinea pigs were operated on at day 7 or at the day of exitus. Cultures were made from a homogenized spleen and liver suspension. Four strains were isolated by the passage method (Appendix Table).
|
|
|||||||||
|
|||||||||
|
EID Home | Top of Page | Ahead-of-Print | Past Issues | Suggested Citation | EID Search | Contact Us | Accessibility | Privacy Policy Notice | CDC Home | CDC Search | Health Topics A-Z |
||
This page posted March
21, 2006 |
||
Emerging
Infectious Diseases Journal |
||