Studies on Mediterranean leishmaniasis. 2. Asymptomatic cases of visceral leishmaniasis

In 1971-72 an outbreak of visceral eishrnaniasis (VL) occurred in the Emifia-Romagna region, Northern Italy (P~WPXGLION ~ et al., 1974a). Castel San Pietro Terme was one of the most affected com-munes. Between June and October 1972 sera from 655 people resident in the village and surrounding farm houses and from 52 other people who had resided in the area during the transmission season (summer 1971) together with subjects who later developed visceral eishmaniasis were tested by a complement fixation test using BCG antigen (BAAR reaction after DF, ALENC ~ et al., 1966, 1968). 282 sera from people living in the same area but far from the affected focus were tested by the same method as a control1-. All subjects, mostly males, were examined following invitation by the health authori-ties to co-operate in the research. For the most part they were peasants or people with country activities. Results Out of the first group of 655 people 24 (3.7%) were positive; 21 with titres ranging from 10 to 40 and 3 with titres of>80. Of the second group (52 people) 10 (19.2%) were positive with titres of from 10 to 40. None of the 282 control sera were positive. Those subjects with positive sera gave no past or present history of VL with the exception of 4 who gave a recent history of fever and periods of unexplained asthenia. None showed any physical signs of VL