The first introduced malaria case reported from Sri Lanka after elimination: implications for preventing the re-introduction of malaria in recently eliminated countries

• Published in: Malaria Journal
• Main Authors: Vissundara M. Karunasena, Manonath Marasinghe, Carmen Koo, Saliya Amarasinghe, Arundika S. Senaratne, Rasika Hasantha, Mihirini Hewavitharana, Hapuarachchige C. Hapuarachchi, Hema D. B. Herath, Rajitha Wickremasinghe, Kamini N. Mendis, Deepika Fernando, Dewanee Ranaweera
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2019
• Subjects: Introduced malaria; Plasmodium vivax; Prevention of re-introduction; Malaria in Sri Lanka; Reactive case detection; Entomological surveillance; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doi.org/10.1186/s12936-019-2843-6; https://doaj.org/article/b78c2a82bb7c495e809c9329a545beff

Abstract Background There has been no local transmission of malaria in Sri Lanka for 6 years following elimination of the disease in 2012. Malaria vectors are prevalent in parts of the country, and imported malaria cases continue to be reported. The country is therefore at risk of malaria being re-established. The first case of introduced vivax malaria in the country is reported here, and the surveillance and response system that contained the further spread of this infection is described. Methods Diagnosis of malaria was based on microscopy and rapid diagnostic tests. Entomological surveillance for anophelines used standard techniques for larval and adult surveys. Genotyping of parasite isolates was done using a multi-locus direct sequencing approach, combined with cloning and restriction fragment length polymorphism analyses. Treatment of vivax malaria infections was according to the national malaria treatment guidelines. Results An imported vivax malaria case was detected in a foreign migrant followed by a Plasmodium vivax infection in a Sri Lankan national who visited the residence of the former. The link between the two cases was established by tracing the occurrence of events and by demonstrating genetic identity between the parasite isolates. Effective surveillance was conducted, and a prompt response was mounted by the Anti Malaria Campaign. No further transmission occurred as a result. Conclusions Evidence points to the case of malaria in the Sri Lankan national being an introduced malaria case transmitted locally from an infection in the foreign migrant labourer, which was the index case. Case detection, treatment and investigation, followed by prompt action prevented further transmission of these infections. Entomological surveillance and vector control at the site of transmission were critically important to prevent further transmission. The case is a reminder that the risk of re-establishment of the disease in the country is high, and that the surveillance and response system needs to be sustained ...