[Acute gastroenteritis caused by a Vibrio cholerae non-O1, non-O139 strain harboring a genetic region homologous to the VpaI-7 pathogenicity island]

Pathogenic Vibrio cholerae isolates, the etiologic agents of cholera, generally express one of two O antigens (O1 or O139). Most environmental isolates are nonpathogenic and are referred to as "non-O1, non-O139". However some V. cholerae non-O1, non-O139 strains are clearly pathogenic and have caused outbreaks or sporadic cases of gastroenteritis and extraintestinal infections in humans. We report a case of acute gastroenteritis by a V. cholerae non-O1, non-O139 harboring a genetic region homologous to a segment of the VpaI-7 V. parahaemolyticus pathogenicity island.

[Bacteremia and endarteritis cases secondary to Campylobacter spp. in a metropolitan hospital: our experience along a quarter of a century]

Six cases of bacteremia and one of endarteritis were identified between 1986 and 2010 in a general hospital in Chile. Five of these cases occurred during the second half of this timeframe, Campylobacter fetus predominated (5 out of 7) and the majority of the infections presented during warmer months. The mean age was 32.4 years (range 19 to 63) all had comorbidities, and main clinical manifestations included fever with diarrhea. Four patients developed hypotension and two septic shock. The latter, associated to C. fetus bacteremia, died before microbiological diagnosis. Six out of 7 patients received antimicrobial therapy. During 2004 and 2010, the rates of Campylobacter spp. positive stool cultures in the same hospital increased 4 times, suggesting an emerging profile. Bacteremia and endarteritis by Campylobacter spp. can develop in vulnerable patients and manifest as fever with or without diarrhea. Finding curved or spiral shaped gram negative rods in blood cultures leads to suspect this pathogen. Species identification is of utmost importance due to antimicrobial resistance especially in C. jejuni. Prognosis is unfavorable due to host characteristics, and case-fatality rate is high.

[Vibrio parahaemolyticus bacteremia: case report and literature review]

Vibrio parahaemolyticus is a facultative anaerobic gram negative rod responsible of sea food-associated diarrhoea. Although less common, it also causes wound infections and bacteraemia. We present a case of bacteraemia by this agent and a review of the literature.

[Seroepidemiological evidence of human exposure to Anaplasma sp in Santiago, Chile]

OBJECTIVES AND METHODS

To find more evidence of human exposure to Anaplasma sp in Chile, we studied 108 contacts of dogs with canine ehrlichiosis (CE) (risk group) and 61 persons without tick or CE cases contact (control group). A survey including risk factors and history of diseases compatible with ehrlichiosis/ anaplasmosis was applied to the risk group. Serum IgG anti-Anaplasma sp antibodies were determined in both groups.

RESULTS

A significant difference was found in the prevalence of anti-Anaplasma sp antibodies in the risk group compared with the control group (18,5 versus 3,3%), p < 0,005. No risk factors associated to seropositivity were found, nor persons with history suggesting ehrlichiosis/anaplasmosis. Ninety four percent of the houses of the risk group had tick infestation.

DISCUSSION

A greater risk of exposition to Anaplasma sp is documented in people living in close contact with CE cases and in houses with tick infestation.

[Risk factors and frequency of positive antibodies for leptospirosis in a sub urban population near Santiago]

BACKGROUND

Leptospirosis is a zoonotic disease and its incidence is known in Chile since 2002, when it was incorporated as a disease that must be reported to health authorities. A serologic survey for leptospirosis was performed in humans and animals from a farm in a semi urban area in Santiago Chile, after the death of a farmer due to Weil disease in that place.

AIM

To report the prevalence of antibodies against leptospirosis and to determine exposure to infection risk factors in the humans and domestic animals studied in this survey.

MATERIAL AND METHODS

Antibodies were detected by IgM immunodot and indirect haemagglutination test in 61 humans (43 male, aged 5 to 70 years) and by microscopic agglutination test (MAT) in 44 animals. A questionnaire was applied to determine their exposure to risk factors for infection with Leptospira.

RESULTS

Seventy two percent of the studied population were farm workers and 70% had activities that required contact with water from canals, 41% cleaned closed places where rodents were present. Other risk factors detected were lack of sewage and waste disposal, high level of rodent infestation and disposal of faeces into canals used for watering. Two humans (3.3%) and six animals (1 bovine and 5 rodents) had positive antibodies. Among animals, antibodies against Leptospira serovar pomona and icterohaemorragiae were detected.

CONCLUSIONS

In Chile, leptospirosis exists not only in rural areas but semi urban ones close to Santiago, although the prevalence is low. Education is necessary among semi urban population to avoid infection.