PUNE: Pune district has earned the dubious distinction of recording about 92% of the state's chikungunya cases and ranks second in terms of dengue incidences in Maharashtra .The latest report of the state health department brought the alarming figures to the fore. Dengue and chikungunya are both transmitted by the Aedes aegypti mosquitoes.The overall tally shows that dengue cases have almost doubled this year. But what strikes most is the 13-fold increase in chikungunya cases in the first nine months of this year compared to the corresponding period last year.The state has recorded 439 cases of chikungunya between January and August this year as against only 35 in the same period last year. Last year's chikungunya case tally surged from September onwards with a total of 207 cases registered till December-end. The state health department's latest report, which considers only the data of government-designated testing and sentinel centres for dengue and chikungunya, revealed this. The report does not take into account data from private hospitals citing that they use rapid test kits, which may give false positive reports.Going by the current surge in cases, this year's chikungunya case tally is likely to surpass the 2011's 467 cases.The state has reported a total of 2,572 dengue cases between January and August this year as against 1,378 recorded during the corresponding period last year.The state's health department has blamed the prevailing weather conditions for the spurt in the mosquitoborne diseases. “The drizzle and showers witnessed towards the end of August resulted in water accumula tion, creating conducive breeding grounds for Aedes aegypti -the mosquito that causes dengue and chikungunya. The low fatality rate of dengue indicates better surveillance and timely diagnosis and treatment,“ said Kanchan Jagtap, the joint director of the state health department.Experts are intrigued how Mumbai remained relatively less-affected by both the viral ailments creating havoc in Pune. “Mumbai is hot and humid, whereas the climate in Pune fluctuates.The rapid and drastic change in the daily weather probably helps the virus or the vector to thrive. Eco-climatic conditions often have a huge role to play, particularly when the vector is mosquito,“ said senior scientist A C Mishra, former director of National Institute of Virology Although the number of dengue cases has shown a steady rise every year, the mortality rate has been going down. The overall mor tality rate of 1.2% in 2007 dropped to 0.25% in 2013. This reduction is probably the result of cumulative effects of better patient management, increased diagnostic capabilities and better reporting.State health officials blamed their counterparts in the Pune Municipal Corporation for the spiralling cases of dengue and chikungunya. “We had instructed the Pune Municipal Corporation (PMC) and Pimpri Chinchwad Municipal Corporation (PCMC) health officials to initiate entomological surveillance and other control measures in a meeting before monsoon. The PCMC health officials diligently implemented the suggested measures but the health officials of PMC were lax,“ said Balkrishna Kamble , assistant director (vector-borne diseases), state health department.PMC woke up to initiating the control measures from mid-August. “Till then, their surveillance and control measures were inadequate.One of the reasons was staff crunch in the insect control department. The posts were filled up on contract only in August,“ said activist Sanjay Dabhade.Kalpana Baliwant, the head of the insect control department of PMC, said, “Initially, we have filled up the required posts and initiated house-to-house surveillance from August 16. We found over 6,000 properties harbouring larvae of denguecausing mosquitoes. We have initiated multi-prong approach. People also need to see they do not facilitate mosquito breeding in and around their premises.“(With inputs from Sumitra DebRoy from TOI, Mumbai)