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Published on: October 11, 2022
Reemergence of rickettsiosis in Oran, Algeria
Nadjet Mouffok1, Anwar Benabdellah, Hervé Richet
1Centre Hospitalier Universitaire d'Oran, 72 boulevard Benzedjeb, 31 000 Oran, Algeria. nadjmouf_31@yahoo.fr
Abstract:
The presumptive cases of Mediterranean spotted fever have been identified in 1993 and since that time, its frequency has steadily increased. The prospective study, in summer 2004, was conducted in order to present the descriptive clinic and epidemiology, to identify more severe forms, the presence of the multiple eschars, and different rickettsial strains caused the disease in our region. In Oran, the cases were diagnosed clinically. In Marseille, serum specimens were tested by IFA using the panel of eight rickettsial antigen; Western blot and cross-adsorption studies were also performed in order to confirm the diagnosis. Ninety-three patients clinically diagnosed were recorded from July 3 to October 28, 2004. Eighty percent were male, the mean age was 44.3 years, 90% were exposed to dog and 32% reported tick bites. Clinical signs were as follow: presence of underlying disease (44%), sudden onset (78%), fever (100%), loss of weight (63%), conjunctivitis (43%), and a tache noire was noticed in 70%. Interestingly, two patients had two and three eschars, respectively. The rash was maculopapular (palm and sole) and purpuric in nine cases. Doxycycline was the most antibiotic (91%) with favourable outcome in 91% of the cases. Malignant form with death is reported for three patients (3.2%). Among the 93 patients, 104 serum from 65 patients were tested (serums of others patients were lost or ticket not found on tube. Sixty-three patients out of 65 had a positive serology by IFA with cross-reactive antibodies especially between R. conorii, R. felis and/or R. typhi. Two others negative serology were: one precocious serum and second from the patient, which presented symptoms of MSF and tested two serums, Western blot and cross-adsorption.
Insights
Mediterranean spotted fever (MSF) cases increased, with a 2004 study detailing clinical and epidemiological features. Doxycycline showed a 91% favorable outcome, though severe forms and deaths occurred.
Area of Science:
- Infectious Diseases
- Epidemiology
- Microbiology
Background:
- Mediterranean spotted fever (MSF) incidence has risen since 1993.
- Understanding regional clinical and epidemiological patterns is crucial for disease management.
Purpose of the Study:
- To describe the clinical and epidemiological characteristics of MSF in Oran and Marseille.
- To identify severe MSF forms, multiple eschars, and circulating rickettsial strains.
- To evaluate treatment outcomes and serological confirmation methods.
Main Methods:
- Prospective study conducted from July to October 2004.
- Clinical diagnosis in Oran; serological confirmation (IFA, Western blot, cross-adsorption) in Marseille.
- Data collection on patient demographics, exposure history, clinical signs, and treatment.
Main Results:
- 93 patients diagnosed; 80% male, mean age 44.3 years; 90% dog exposure, 32% tick bites.
- Common signs: fever (100%), sudden onset (78%), tache noire (70%), underlying disease (44%).
- Doxycycline effective (91% favorable outcome); 3.2% mortality; cross-reactive antibodies detected in 63/65 patients.
Conclusions:
- MSF presents with diverse clinical signs, including multiple eschars and purpuric rash.
- Doxycycline is an effective treatment, but severe cases and deaths occur.
- Serological testing reveals cross-reactivity, highlighting the need for precise diagnostic methods.
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