Kolkata: Six people who were diagnosed with dengue died on Friday, taking this year's toll in West Bengal to over 30, officials said.

Two patients died at a private hospital in Kolkata while undergoing treatment. One of them was a resident of Salt Lake and the other was from Bagha Jatin, they said.

Two persons died in Ghatal in Pachim Medinipur, and two persons died in nearby Kharagpur, they added.

Meanwhile, a migrant worker who returned from Kerala with symptoms similar to Nipah tested negative, a Health Department official said after receiving the report from the National Institute of Virology (NIV) where his sample was sent.

The man is undergoing treatment at the Beliaghata ID Hospital and has a high fever, nausea and throat infection, he said.