Former Punjab chief minister Shehbaz Sharif on Thursday said that the outbreak of dengue virus was "hugely worrisome", as the number of patients affected by the disease continues to grow.

Sharif called it "unfortunate" that the virus had emerged again and said that the previous PML-N government had worked with a "missionary zeal to overcome the epidemic". He added that a "complete health infrastructure, along with SOPs, was put in place to make sure that it does not recur again".

Over the last month, more than 500 people have been diagnosed with dengue in Rawalpindi alone and cases have also emerged in Khyber Pakhtunkhwa. Several cases have also been reported in Azad Jammu and Kashmir. Yesterday, two patients diagnosed with dengue passed away in Rawalpindi's Benazir Bhutto Hospital.

Earlier, an official of the health department told Dawn on condition of anonymity that Rawalpindi was witnessing dengue spike after a gap of four years.

He said in 2015, more than 4,000 dengue patients were reported in the city and cantonment areas, but this year the number would increase.

According to the official, the main reason of spread of dengue virus was that the district administration and health authorities failed to carry out fumigation in most union councils in the city and wards of cantonment.