India, Jan. 13 -- Two suspected cases of Nipah virus were detected in West Bengal's North 24 Parganas district, prompting authorities to step up vigil, top officials of the state government said on Monday. Two patients, both nurses, are critical and they are on ventilator. "Two suspected cases of Nipah virus have been reported. They worked in the same hospital in Barasat. We have started contact-tracing," Nandini Chakravorty, state chief secretary, said. One of the nurses is a resident of East Midnapore and the other of East Burdwan. They had gone home in December and fallen ill, officials added. P10...