Human trichinellosis in Argentina

Abstract number: 1133_119

Bolpe J., Ledesma M., Benítez M., Cecchini D, González Ayala S.

Objective:  

To describe the epidemiologic, clinical and laboratorial aspects of human trichinellosis.

Methods:  

Database of the Epidemiologic Surveillance System of Buenos Aires State, Argentina, 1/2000–9/2004 was processed with Excel and Statistics software. The outbreak investigation was routinely performed by county and state health authorities. Trichinosis case was suspected based on eosinophilia in conjunction with compatible symptoms and a dietary history (pork meat). Diagnosis was confirmed by serologic test (indirect immunofluorescence, IFI), and/or identification of larvae in the suspect meat (digestion of muscle tissue in artificial gastric juice followed by examination of the sediment for larvae).

Results:  

One thousand and one hundred twenty eight cases and 65 outbreaks were studied. The distribution by gender was asymmetrical, male 58.2% (n = 656). The median age was 33 years (range 1–97). Ninety eight per cent of the cases (n = 1103) occurred in the context of an outbreak. All cases were related to the consumption of pork meat, and 72.1% of the suspect food was from animals slaughtered and sold without sanitary inspection. Ninety seven per cent of the cases (n = 1094) presented clinical symptoms and/or signs. The most frequent were: myalgias 66.0% (n = 745), headache 50.3% (n = 567), periorbital edema 48.9% (n = 552), fever 45.2% (n = 510), diarrhoea 27.1% (n = 306), nausea and vomiting 14.7% (n = 166). The median for symptoms/signs was 3 (range 0–8). Eosinophilia over 6% was observed in 42.9% (n = 484). IFI was positive in 65.3% (n = 737). The suspect food was available for identification of larvae in 11.7% (n = 132) of the cases. The amount of larvae per gram ranged from 1 to 150.

Conclusion:  

Trichinellosis is a zoonotic infection related to the ingestion of undercooked pork meat. In our study most of the cases occurred in the context of an outbreak. We found a high percentage of cases related to the consumption of pigs and their derivatives that escaped from sanitary inspection. This shows the lack of adequate bromatological control in our environment. The frequency distribution of symptoms and/or signs was similar to other series. In an appropiate epidemiologic context, characteristic clinical symptoms strongly suggest the diagnosis of trichinellosis, which can be confirmed with serologic tests and/or identification of larvae in the involved meat. Health education for breeders, producers and consumers is very important in order to prevent future outbreaks.