Epidemiological screening of an epidemic of imported cutaneous leishmaniasis in Luoyang City / 中国血吸虫病防治杂志

ABSTRACT

Objective To understand Leishmania infections among employees of China Petroleum First Construction Corporation returning from Uzbekistan, and take timely actions to prevent the spread of the epidemic. Methods Questionnaire survey was conducted to collect screening subjects’information. Palpation of the liver, spleen and superficial lymph nodes was performed by a physician, and the lesions on the frequently exposed skin were detected by a dermatologist. In addition, the liver and spleen sizes were measured using B-mode ultrasonography, and serum samples were collected to be subjected to an rK39-based rapid diagnostic test for detection of visceral leishmaniasis. Leishmania was detected using microscopy in the specimens sampled from the lesioned skin, and the parasites species was identified using molecular assays in parasitologically positive specimens. Results Among the 181 employees screened, enlarged cervical lymph nodes were palpable in 6 subjects, and skin lesions were found in 12 cases. B-mode ultrasonography displayed hepatosplenomegaly in 5 cases, and rK39 test were positive in 3 serum samples. Two classical lesioned skin specimens were sampled, and Leishmania was detected in one specimen. The promastigote DNA was extracted and two fragments of 120 bp and 350 bp in sizes were amplified using PCR assay with K13A/K13B and L5.8S/LITSR primers specific to Leishmania. The two amplification products were 90% and 98% homologous to the corresponding sequences of L. major (GenBank accession numbers EU370906.1 and FN677342.1). Conclusions Six patients with cutaneous leishmaniasis were screened, including 2 uncured cases. One uncured case was diagnosed as imported cutaneous leishmaniasis caused by L. major infection.