ABSTRACT
Cutaneous leishmaniasis (CL) is often considered a 'great imitator' and is the most common form of leishmaniasis. The Leishmania species responsible for CL varies among countries, as these species exhibit specific distribution patterns. The increased mobility of people across countries has resulted in the imported incidences of leishmaniasis caused by non-endemic species of Leishmania. During 2023, we confirmed three CL cases caused by L. major from Kerala, India, and upon detailed investigation, these were identified to be imported from the Middle East and Kazakhstan regions. This is the first report of CL caused by L. major from Kerala. The lesion morphology, detection of anti-rK 39 antibody and Leishmania parasite DNA from the blood samples were the unique observations of these cases. Kerala, being an emerging endemic zone of visceral leishmaniasis (VL) and CL, the imported incidences of leishmaniasis by non-endemic species can pose a significant threat, potentially initiating new transmission cycles of leishmaniasis caused by non-endemic species.
Subject(s)
Leishmania major , Leishmaniasis, Cutaneous , India/epidemiology , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/diagnosis , Humans , Male , Leishmania major/isolation & purification , Leishmania major/genetics , Adult , Female , Communicable Diseases, Imported/parasitology , Communicable Diseases, Imported/epidemiology , Middle Aged , DNA, Protozoan/genetics , Antibodies, Protozoan/bloodABSTRACT
BACKGROUND: Culex quinquefasciatus is a notorious vector known to transmit pathogens such as Wuchereria bancrofti (causing Lymphatic filariasis) and flaviviruses such as West Nile virus in India and St. Louis Encephalitis virus in the USA. It is the vector of the Rift Valley Fever virus, also on the African continent. Mosquitoes also harbor other non-pathogenic insect-specific flaviviruses (ISFs), such as Culex flavivirus (CxFV) and Aedes flavivirus. Recent studies have implicated ISFs interfering with the vectorial efficiency of the pathogenic arbo-viruses. METHODS: One hundred specimens of the Cx. quinquefasciatus population in two urban areas in Kerala State, India, were screened to have an understanding of the prevalence of these flaviviruses in this vector species. Viral RNA was extracted from individual specimens and was subjected to RT-PCR towards amplification of the CxFV non-structural protein 5 (NS5) gene. RESULTS: Among the 100 specimens, 7.0% were found to be harboring CxFV infection. The phylogenetic analysis of the gene sequences showed that the virus isolates were genetically related to Kenya, with 98-99% sequence similarities. CONCLUSION: This is the first report on the occurrence of CxFV from Cx. quinquefasciatus from India. The occurrence of these viruses in mosquitoes could play a critical role in disease vector management.
Subject(s)
Culex , Culicidae , Flavivirus , Humans , Animals , Culex/genetics , Phylogeny , Mosquito Vectors/genetics , Flavivirus/geneticsABSTRACT
OBJECTIVES: Following the Public Health Emergency of International Concern declared on Zika by the World Health Organization during 2016, the Indian Council of Medical Research carried out nationwide vector surveillance for Zika and Dengue viruses (ZIKV and DENV) in India as a preparedness measure in 2016-19. METHODS: High-risk zones distributed to 49 Districts in 14 states/union territories were included in the study. Seven ICMR institutions participated, following a standard operating protocol. Aedes specimens sampled weekly were processed by multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) for ZIKV/DENV and random samples crosschecked with real-time RT-PCR for ZIKV. RESULTS: Altogether, 79 492 Aedes specimens in 6492 pools were processed; 3 (0.05%) and 63 (0.97%) pools, respectively, were found positive for ZIKV and DENV. ZIKV infections were recorded in Aedes aegypti sampled during the 2018 sporadic Zika outbreak in Jaipur, Rajasthan. However, these belonged to the Asian lineage of the virus, already circulating in the country. Both Ae. aegypti and Aedes albopictus distributed to 8 states/union territories were found to be infected with DENV. Both sexes of Ae. albopictus were infected, indicating transovarial transmission. CONCLUSION: This investigation evinced no active transmission of the American lineage-pandemic Zika virus in India during the pandemic period.
