Cutaneous leishmaniasis in primary school children in the south-eastern Iranian city of Bam, 1994-95.

Between August 1994 and July 1995, 11,517 primary school children aged 6-11 years in the south-eastern Iranian city of Bam, comprising 5560 (48.3%) girls and 5957 (51.7%) boys, were examined for the presence of active lesions or scars of cutaneous leishmaniasis (CL). There was a trend towards increasing prevalence with age, the prevalence being 10.7% in 6-year-old and 20% in > or = 11-year-old children. Overall, 1.3% of the children had active lesions and 14.3% had scars. There was no significant difference between the sexes in the prevalence of active lesions and/or scars. Of the children examined, 54 (0.5%) had leishmaniasis recidivans: 19 girls (35.2%) and 35 boys (64.8%). The number of active lesions or scars per child ranged from 1 to 10. The majority (82.3%) had 1 lesion, 12.4% had 2 lesions, and 5.3% had > or = 3. The average number of lesions was 1.08 (1.03 in girls and 1.18 in boys). The face was the part of the body most commonly involved (63.6%), followed by the hands (20.9%), legs (12.8%) and other parts of the body (2.7%). Examination of isolates from 14 children revealed that in 13 (92.9%) the causal organism was Leishmania tropica and in the other (7.1%) L. major. The survey indicates that the geographical distribution of CL is far wider than previously thought. It also shows that Bam is a suitable areas for a vaccine field trial.

PIP: Cutaneous leishmaniasis, caused by Leishmania tropica, is endemic in southeastern Iran's Kerman Province, including the city of Bam. As a first step toward selecting different arms of a vaccine field trial, all 11,517 primary school students 6-11 years old from Bam were examined between August 1994 and July 1995 for the presence of active lesions or scars of cutaneous leishmaniasis. Overall, 1.3% of children had active lesions and 14.3% had scars. Prevalence tended to increase with age, but there was no difference on the basis of sex. 54 children (0.5%) had leishmaniasis recidivans. The number of active lesions or scars per child ranged from 1 to 10 (average, 1.08). Body parts most frequently affected were the face (63.6%), hands (20.9%), and legs (12.8%). Examinations of isolates from 14 children revealed that L. tropica was the causal organism in 13 (92.9%). These findings indicate that cutaneous leishmaniasis is even more widely distributed throughout Iran than previously thought, probably as a result of agricultural and unplanned urban development. They further confirm that Bam is a suitable location for a vaccine field trial.

Randomised vaccine trial of single dose of killed Leishmania major plus BCG against anthroponotic cutaneous leishmaniasis in Bam, Iran.

BACKGROUND: A vaccine consisting of a single dose of whole-cell autoclave-killed Leishmania major (ALM) mixed with BCG was assessed in comparison with BCG alone against anthroponotic (human to human transmission) cutaneous leishmaniasis in a randomised double-blind trial in Bam, Iran. METHODS: 3637 schoolchildren, aged 6-15 years, with no history of cutaneous leishmaniasis and no response to a leishmanin skin test, were randomly assigned to receive 1 mg ALM mixed with BCG (n = 1839), or BCG alone (n = 1798). Safety of the vaccine and the incidence of confirmed cases of cutaneous leishmaniasis were followed up for 2 years. FINDINGS: Side-effects were those usually associated with BCG vaccination, but tended to persist longer in the ALM + BCG group. After exclusion of four cases occurring within 80 days of vaccination (one in the ALM + BCG group and three in the BCG group), the 2-year incidence of cutaneous leishmaniasis did not differ significantly between vaccine and BCG groups: 2.8% vs 3.3%, respectively (total cases 112). A sex-stratified analysis showed that in boys the vaccine conferred a protective efficacy of 18% and 78% for the first and second years, respectively--a crude 2-year overall protection of 55% (95% CI 19-75%, p < 0.01). In the first 9 months after vaccination, there was a non-significant excess of cases in the ALM + BCG group (25 vs 16), whereas the incidence of cutaneous leishmaniasis thereafter was significantly reduced in the ALM + BCG group (27 vs 44, p < 0.05). INTERPRETATION: A single dose of ALM + BCG was safe and more immunogenic than BCG alone, as measured by leishmanin skin test. The exact reason for the apparent protective effect of the vaccine in boys is unknown, and may be a chance finding. However, since boys are more exposed to the infection, which is indicated by higher disease prevalence in boys in this study population, the preferential protective effect in boys may have resulted from a greater booster effect produced by repeated exposure to infected sandflies. Booster injections or alternative adjuvants should be tried to improve the potential efficacy of this vaccine.