Cutaneous leishmaniasis (CL) continues to be an increasing public health problem in Iran. Shiraz, a city in Fars Province in southwestern Iran, is one of the endemic foci of CL. However, there is no formal report of endemicity of CL in rural areas of Shiraz. To our knowledge, this is the first report of an epidemic of zoonotic CL in this area. The purpose of this study was to examine the epidemiological features of leishmaniasis in three villages in rural areas of Shiraz and to identify the causative species of leishmaniasis using nested PCR with clinical direct samples. The prevalence of infection among 1000 inhabitants of the three villages was 23.2%. Prevalences of ulcers and scars were 7 and 16.2%, respectively. The most infected age group was 0-9 years, with a rate of 14.2%. Children are more than twice as susceptible to the infection. In this study, the Leishmania major strain was identified in the majority of cases. The results of this epidemiological study indicate a high prevalence of leishmaniasis in rural areas of Shiraz.

Over the last decade, the incidence of visceral leishmaniasis (VL) has increased in many districts of the province of Fars, in southern Iran. Recent epidemiological reports indicate that asymptomatic human infections with Leishmania infantum (the causative agent of VL throughout the Mediterranean basin) occur more frequently in Iran than was previously believed. Between 2004 and 2006, blood samples were collected from 802 apparently healthy subjects from communities, in the north-west and south-east of Fars province, where VL cases had been recorded. Each of these samples was tested for anti-Leishmania antibodies, in direct agglutination tests (DAT), and for L. infantum kinetoplast DNA, in PCR-based assays. Of the 426 subjects from north-western Fars, eight (1.9%) were found seropositive and 68 (16.0%) PCR-positive. The corresponding values for the 376 subjects from south-eastern Fars were lower, with five (1.3%) seropositive and 32 (8.5%) PCR-positive. Of the 100 PCR-positive subjects, 18 (18.0%) each lived in a household in which there had been a case of VL, and six (6.0%) had had VL themselves (in each case, more than a year before the blood sampling for the present study). Although 21 of the PCR-positives have now been followed-up for at least 18 months, none has developed symptomatic VL. Since positivity in the PCR-based assay probably indicated the presence of L. infantum amastigotes in the peripheral blood of 12.5% of the subjects, it is clear that asymptomatic human carriers of L. infantum are quite common in the study areas and probably act as reservoirs in the transmission of the parasite, to humans and to dogs, by sandflies.

The incidence of zoonotic cutaneous leishmaniasis (ZCL), which is endemic in several parts of Iran, has recently increased in the rural areas of the northern district of Damghan, in Semnan province. Between 2001 and 2004, as part of an investigation of this worrying trend, wild rodents in this region were caught and checked, by the microscopical examination of liver and spleen smears, for leishmanial infection, to see which species were acting as 'reservoir' hosts. Overall 298 Nesokia indica, 29 Meriones libycus, 10 Mus musculus and two Microtus socialis were caught. Most of the N. indica (61%) and Me. libycus (52%) but none of the other rodents were found smear-positive for leishmanial amastigotes. When PCR was used to test scrapings from 50 of the smears (of which 25 had been found to harbour amastigotes, by microscopy), 29 (58%) of the smears were found positive for the kinetoplast DNA of Leishmania major; none was found positive for any other Leishmania species. Nesokia indica and Me. libycus are therefore incriminated as the main 'reservoir' hosts of L. major in Damghan.

In Iran, Leishmania major or L. tropica cause almost all of the human cutaneous leishmaniasis (CL). Unfortunately, the detection methods frequently used for CL (the microscopical examination of direct smears or the culture of biopsies) are not very sensitive and the Leishmania species causing each case of CL in Iran is usually only tentatively identified from extrinsic factors, such as the case's clinical manifestations and region of residence. Recently, however, a nested PCR that targets the parasites' kinetoplast DNA has been used in the city of Ahvaz (the capital of the province of Khouzestan, in south-western Iran) to confirm the microscopical diagnosis of CL and to identify the causative parasites, to species level. Smears from the lesions on 100 suspected cases of CL were fixed, stained with Wright's eosin-methylene blue, and checked for amastigotes under a light microscope. Scrapings from the same smears were then tested for leishmanial DNA, using a nested PCR that allows the DNA from L. tropica to be identified and distinguished from that of L. major. The 100 smears investigated were all found amastigote-positive by microscopy and PCR-positive for either L. major DNA (97 smears) or L. tropica DNA (three smears). The predominant species causing CL in Ahvaz is therefore L. major.

Leishmaniasis is one of the infectious parasitic diseases of highest incidence in the world. Cutaneous Leishmaniasis (CL) has long been reported in Shiraz, Southern Iran. There is a need to find a sensitive and specific method for treatment and control of the disease. We have compared the sensitivity of the conventional methods microscopy and cultivation of lesion scrapes against PCR amplification of parasite kinetoplast DNA from these samples. The samples (n=219) were obtained from the patients clinically suspected of CL. The smears were stained with Giemsa for microscopy and cultured in Novy-Nicolle-McNeal (NNN) blood agar for promastigote growth. For PCR, the dry smears were scraped off the slides and DNA was extracted. The positive rates from 219 specimens were 76.71%, 50.68%, and 93.61% for microscopy, cultivation, and PCR, respectively. The highest correlation was found between PCR and microscopy method (P=0.014). In PCR assay, 95.61%, 3.9%, and 0.49% of the samples were identified as Leishmania major, L. tropica, and dermatropic L. infantum, respectively. The PCR method appears to be the most sensitive for the diagnosis of CL and is valuable for identifying the other species of Leishmania with confusing dermatropic signs.