Health officials in Davao City, Mindanao, Philippines is warning the public about another mosquito borne viral threat, Japanese encephalitis, after a 52-year-old man from Bacaca was confirmed positive for the serious infection, according to a local media report.

Japanese encephalitis geography/CDC
Japanese encephalitis geography/CDC

According to Davao City Health Officer, Dr. Josephine Villafuerte, the patient survived and has been discharged from the hospital; however, he now suffers from neurologic diseases, including memory lapses.

Villafuerte warns, “You should not be so complacent that there is just one case. We have to take into consideration that we have a lot of mosquito-borne illness, we have dengue, we have filaria, we have Japanese encephalitis, we have other illnesses also.”

Japanese encephalitis (JE) is the most important cause of viral encephalitis in Asia. About 68,000 clinical cases are reported annually. It usually occurs in rural or agricultural areas, often associated with rice farming.

LISTEN: Dr Anna Lena Lopez, a pediatric infectious disease specialist and research associate professor at the University of the Philippines in Manila discusses JE and the vaccine

JE virus is transmitted to humans through the bite of infected Culex species mosquitoes, particularly Culex tritaeniorhynchus.

Most JE virus infections are mild (fever and headache) or without apparent symptoms, but approximately 1 in 250 infections results in severe disease characterized by rapid onset of high fever, headache, neck stiffness, disorientation, coma, seizures, spastic paralysis and death. The case-fatality rate can be as high as 30% among those with disease symptoms.

There is a protective vaccine against Japanese encephalitis virus.

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