Kolkata, Jan. 14 -- Samples of both suspected Nipah virus cases in West Bengal have tested positive, the National Institute of Virology (NIV) in Pune confirmed on Tuesday, with officials familiar with the matter saying that the two patients, both nurses, are critical and on ventilator. The two nurses - a male and a female - who worked in the same private hospital at Barasat in North 24 Parganas and are currently admitted there. While one is a resident of Nadia, another is a resident of East Burdwan. "They had gone home in December and fell ill. Later they were admitted to the hospital at Barasat, where they worked with symptoms of Nipah virus. Their samples were sent to the National Institute of Virology in Pune for confirmation," an offici...