Awwal 23, 1432 / April 27, 2011, SPA -- Chile has registered a significant increase of new whooping cough cases in Metropolitan Region, its Health Ministry said Tuesday. According to the ministry, 359 cases are recorded in the region, and 60 percent of the patients are infants under one year old, with most under 6 months old. Authorities are keeping a nationwide vigilance of the disease and are monitoring all new cases. So far, a total of 689 children both in 2010 and 2009 have developed the sickness throughout Chile, Xinhua reported. The Health Ministry has warned that although children are most vulnerable to the virus, adults can also catch the cough, so all those who are not vaccinated against the virus should be particularly alert to any signs of infection. Pediatrician Luis Barrueto from the University of Chile said whooping cough is severe and called on people to seek immediate medical attention once showing symptoms. He also called for preventative measures to protect children from getting infected.