Leishmaniasis in Sardinia. 5. Leishmanin reaction in the human population of a focus of low endemicity of canine leishmaniasis

Abstract

About half (640 subjects) of the population of Soleminis, a canine leishmaniasis focus 15 km north of Cagliari, Sardinia, was subjected to the leishmanin skin test. The total positive rate was 9.7%, and that of males was 15.5%. The age trend in the positive rate resembled a hyperbolic curve, with the 0-5 years age group rate being zero and the highest rate (39.3%) occurring in the 55-65 years age group. The Soleminis focus was classified as hypoendemic, with a prevalence of canine leishmaniasis of about 3%. Dog surveillance, land reclamation and changes in population habits during the last few decades are considered to be responsible for the reduction of transmission to man.

Endemic Transmission of Visceral Leishmaniasis in Bhutan

“…7 Following the international consensus definition, the LST was considered positive if the mean of the two measurements was 5 mm or greater. 8,9 The Institutional Review Board of the Centers for Disease Control and Prevention reviewed the protocol and determined that the activity met the criteria for an outbreak investigation, and as such was not classified as research and did not require formal Institutional Review Board approval.…”

Socio-economic and environmental factors associated with Montenegro skin test positivity in an endemic area of visceral leishmaniasis in northern Morocco

“…29 There were no or very low incidence of positive reactions in children under the age of 15 years but this increased in older populations. 27,29 The highest percentage of asymptomatic carriers (14.05%) and the highest nodule size was found in Taounate compared to My Yacoub, where the percentage of asymptomatic carriers was only 8.7%. In contrast, the Ministry of Health 2006 report 5 confirms that the incidence of visceral leishmaniasis per 100,000 children under 15 years of age is higher in My Yacoub (33%) than in Taounate (12.1%).…”

“…33 In Italy, the leishmanin skin test positivity rate of males was only slightly higher than that of females, the tendency of women to work indoors during the time of day when transmission occurs, together with the exophily of the vector P. perniciosus, may explain this difference. 27 We suggest that males are more exposed to infectious bites due to socio-cultural factors. Males can stay outdoors later and spend more time outside on the whole.…”

“…This percentage was comparable to that found in Spain (11.5%) 25 and in Brazil, where the incidence of the infection was 10.8% when determined by MST on children aged 0-5 years. 26 Studies conducted in high-risk areas of VL in southern Europe using MST indicated a high frequency of subclinical leishmaniasis: 9.7% in Sardinia (Italy), 27 15.3% in Tuscany (Italy), 28 and 46.8% in the Alpes Maritimes (France). 29 There were no or very low incidence of positive reactions in children under the age of 15 years but this increased in older populations.…”

Humoral and In Vivo Cellular Immunity against the Raw Insect-Derived Recombinant Leishmania infantum Antigens KMPII, TRYP, LACK, and papLe22 in Dogs from an Endemic Area

“…Delayed-type hypersensitivity (DTH) reaction to an intradermal injection of a suspension of inactivated promastigotes (leishmanin skin test, LST) is an easy and semiquantitative test to measure Leishmania -specific CMI in vivo . 8,11 This test has been extensively used in large-scale immunoepidemiological studies in Southwestern Europe as a marker of exposure to Leishmania in humans [12][13][14] and much less in dogs. 15,16 The LST result is usually negative in advances stages of clinical VL and canine leishmaniasis (CanL), 7,8,17 whereas a positive LST result is detected during subclinical infection, 15,16 in early stages of VL and CanL, 18,19 or after successful treatment.…”