Human babesiosis is a zoonosis primarily transmitted through Ixodes ticks and alternatively by routes such as blood transfusions from asymptomatic donors. We report the first case of human babesiosis caused by Babesia divergens in a patient with HIV. This study also focuses on elucidating the possible transmission route of infection in this patient, who received numerous blood transfusions but showed patent symptoms only after splenectomy. A battery of detection tools along with a novel Western-Blot Assay and Enzyme Linked Immunosorbent Assay using the major surface protein of B. divergens (Bd37) as a target were used to evaluate the presence of B. divergens or antibodies against the parasite in samples from the patient and the blood donors involved in this case. A retrospective study of the humoral status against the parasite revealed B. divergens IgG antibodies in one of the implicated donors, but also showed that the patient had been already exposed to the parasite before any transfusion. Thus, this analysis of natural and transfusion transmission routes suggests a pre-existing subclinical babesiosis in the patient.

Diarrheal stool specimens were inoculated into the following media: alkaline peptone water (APW), Bruce-Zochowsky medium (BZ), Campylobacter enrichment broth (CEB), Cantpy-thio broth (CT), and Skirrow blood agar (SK) plate. All media were incubated at 42°C in microaerophilic conditions for 24 h. Afterwards, a new SK plate was inoculated from every liquid medium. Campylobacterjejuni was isolated from 43 of the 259 specimens when CT was used, from 45 when APW was used, from 46 when BZ was used, and from 46 when CEB was used; these totals include specimens that grew after enrichment only, on SK plates only, and both after enrichment and on SK plates. No significant differences were found between the isolates obtained with and without enrichment procedures.

Four hundred thirty-two lactose-negative colonies isolated from human feces on stool differential agar media were flooded with one drop of MUCAP Test reagent (Biolife Italiana S.r.I., Milan, Italy) and observed under a Wood lamp for the development of a blue fluorescence over or around the colony. On the basis of manual and automated conventional tests for the screening of Salmonella spp., the MUCAP Test yielded the following results: 79 true-positives, 314 true-negatives, 35 false-positives, and 4 false-negatives (sensitivity, 95%; specificity, 90%; positive predictive value, 69%; negative predictive value, 99%). The specificity of the test performed on colonies isolated on MacConkey agar (95%) was higher than that performed on colonies isolated on SS agar (88%; P less than 0.03). The MUCAP Test is an easy, rapid, and sensitive method for the screening of colonies suspected of being Salmonella spp., reducing the number of biochemical tests needed.

Chloramphenicol showed good activity against most tested strains of Salmonella spp., Shigella spp., and C. jejuni. The incidence of Salmonella spp. and Shigella spp. was very marked in the hot dry months of the year, rotavirus predominated during the cold months, and no seasonal variations of importance were seen for C. jejuni and G. lamblia.

Diarrheal stools from 263 patients were inoculated on seven selective media: Butzler selective medium, Blaser medium, Skirrow blood agar, Preston campylobacter selective medium, Preston campylobacter blood-free medium, Butzler Virion medium, and modified Preston medium (with amphotericin B [2 mg/liter]). A similar number of Campylobacter jejuni strains were isolated from all the media studied; nevertheless, the presence of competing fecal flora (FF) made the detection of suspect colonies difficult. Preston campylobacter blood-free medium with cefoperazone yielded the greatest number of C. jejuni isolations, and contaminating FF grew in only 9% of the plates showing C. jejuni growth; all the other media allowed the abundant growth of other FF, regardless of whether C. jejuni was isolated from them or not.