A local outbreak of autochthonous Plasmodium vivax malaria in Laconia, Greece--a re-emerging infection in the southern borders of Europe?

OBJECTIVES: Malaria is considered to have been eradicated in Greece and only sporadic cases in travelers are reported. However the migration of populations from endemic countries of Asia to Greece may have caused a re-emergence of the disease.
METHODS: A cluster of nine human malaria cases due to Plasmodium vivax infection in the area of Laconia (southern Peloponnesus) from 2009 to 2010 is presented. Patients were hospitalized in Sparta General Hospital.
RESULTS: Eight patients were diagnosed in 2009 and one in 2010. Two were refugees from Pakistan and Afghanistan and five were Romas living in a local camp. Apart from the two immigrants, no other patient had any history of travel, blood transfusion, or organ transplantation. All patients had a febrile illness, hematological abnormalities, and irregular liver function tests. Parasites were identified in peripheral blood smears, and PCR confirmed the presence of P. vivax. Sensitivity testing showed chloroquine susceptibility. Combined treatment with chloroquine followed by primaquine was completed uneventfully. Entomological surveillance disclosed the presence of Anopheles saccharovi as the predominant mosquito species, however PCR testing failed to identify P. vivax in the mosquito population.
CONCLUSIONS: We have presented the first large outbreak of the local transmission of autochthonous malaria cases in Greece since the 1950s. Enhanced entomological surveillance and early detection of malaria cases are crucial in order to prevent the re-emergence of malaria, not only in Greece, but in Europe as well.