Thiruvananthapuram, May 1 (IANS) A series of contagious diseases, including viral fever, that took a heavy toll in Kerala in the previous years have made a comeback in the state's coastal Alappuzha district.

 
 According to health department officials, several patients have been admitted to government hospitals in Alappuzha with leptospirosis, dengue, Japanese encephalitis (JE) and chikungunya.
 
 Around 13,489 people in the district have been affected with viral fever this year, health officials have said.
 
 Also 25 cases of leptospirosis, eight cases of dengue fever and six cases of JE have been diagnosed, the official said.
 
 While leptospirosis is caused by rodents, dengue, JE and chikungunya are spread by mosquitoes.
 
 A.S. Pradeep, a senior health department official, however, said Sunday there was no cause for concern.
 
 "Surveillance has been stepped and reports are closely monitored," he added.
 
 A laboratory of the National Institute of Virology in the state capital has helped in tracking the diseases more efficiently than before, Pradeep pointed out.
 
 A major outbreak of the diseases in the summer of 2006 claimed over a hundred lives in Alappuzha district, prompting the health department to launch widespread awareness campaigns prior to every summer.
 
 According to Thomas Mathew, professor of community medicine at Thiruvananthapuram Medical College, media reports on the issue are exaggerated.
 
 “Since 2006, there has been a proper system of reporting done by the state health department. Exact data of the prevalence of diseases are available unlike in many other states. It is quite natural that cases would be reported," Mathew told IANS.