India, Aug. 27 -- More than a third of the 570 dengue cases reported so far this year in Delhi remain "untraceable" because of incomplete or incorrect addresses, hampering efforts to identify disease clusters and contain outbreaks, municipal and health officials said on Wednesday.

The lack of traceability is significant as dengue was made a "notifiable disease" in Delhi five years ago under an effort to strengthen surveillance and enable targeted action

According to the public health department's latest vector-borne disease report, of the 570 dengue cases reported till Monday, the Municipal Corporation of Delhi (MCD) has classified 208, or 36.5%, as "untraced" because of incomplete or incorrect addresses. Another 90 cases have been clas...