A second man has died in NSW from Japanese encephalitis in an outbreak that began earlier this year.

The man in his 60s from Corowa, near the Victorian border, was diagnosed with the virus in early March and died in hospital at Albury on Friday.

His death is the second in NSW from the virus, which has infected 13 people in the state since the first cases were detected in late February.

The mosquitoes that spread the virus have declined in number, but NSW Health warns people should still take steps to avoid being bitten, such as avoiding going outdoors at dawn or dusk and steering clear of wetlands and bush areas.

Long sleeves, shoes, socks and insecticide can also help people avoid being bitten.

Japanese encephalitis can cause severe neurological illness including convulsions and reduced consciousness and there is no specific treatment.

The virus does not transmit between people and vaccinations exist to guard against it.

The man's death from Japanese encephalitis came on the same day NSW confirmed its first case of monkeypox in a returned traveller from Europe.

Monkeypox is endemic to central and western Africa, but several cases have been identified in a number of European countries and the United States in recent weeks.