The Epidemic Control Cell of Indian Medical Association in Thiruvananthapuram has sounded a dengue alert in the capital. An epidemiological and entomological investigation conducted by the Cell has revealed that there is a rise in breeding of mosquitoes responsible for the disease. In the wake of the investigation, the Association has warned the government that there would be an imminent outbreak of dengue fever in Kerala and recommended some preventive measures.
The study reveals that though the disease has already hit the state capital although it is in the pre-epidemic stage. The survey recommended some preventive measures including source reduction activities in every domestic surroundings must be undertaken with the help of public to contain the menace prior to the onset of monsoon.
This was informed by a group of doctors who have monitored the investigation under the auspices of IMA's Epidemic Control Cell (ECC).
Dr T Suresh Kumar, chairman of the ECC of IMA said they have initiated the study to make Thiruvananthapuram a dengue epidemic free zone. In all the places where the investigation was conducted, it was found that the density of Aedes albopictus was identified as the predominant Aedes species, which was already incriminated as the vector for Dengue fever. Another vector Aedes aegypti is also present in certain pockets, but its density is very low.
Ever since the Dengue made its presence in the state of Kerala in 1996, there has been increasing incidence of the disease in Thiruvananthapuram with periodic hike. The year 2003 witnessed a massive outbreak of Dengue throughout Kerala, Thiruvananthapuram being the worst hit area. In 2006 and in 2007 there was high incidence of Chikungunya during monsoon season and that was also transmitted by the same mosquitoes, said Dr A Althaf, convener of the Cell.
"In majority of the surveyed areas vector density was found to be more than sufficient for the transmission of the disease. A total of 315 houses were examined to detect the Aedes breeding, and House Index, Container Index and Breteau Index were calculated. Of the six wards where the surveys conducted, certain pockets in Ambalathara, Karamana and Pattom wards showed relatively high vector indices. The survey revealed that both Aedes aegypti and Aedes albopictus co-existed in the study areas, practically, in all types of water containers in the backyards of the houses," Dr Althaf, the senior lecturer in the Medical college told Pharmabiz.
According to their investigation, a peculiarity noticed, regarding the occurrence of Dengue in Thiruvananthapuram, was that the current outbreak did not follow the conventional pattern. Usually the Dengue fever outbreak takes a cyclical occurrence with two to three years interval. As far as the region is concerned, besides the cyclical outbreaks, a lot of Dengue cases were reported in the inter-epidemic periods, thus rendering it to an endemic disease. The data on the Dengue incidence of Kerala also pointed to the fact that in previous years almost 70 per cent of the total confirmed Dengue cases were reported from the capital only.
The health agency however warned that the cyclical incidence of Dengue epidemic was expected to be in the current year. It is likely to occur during post rainy months of July and August. Dr Suresh, the chairman of the Cell said there was a ten-fold increase in the incidence of cases during the current outbreak and the density of vectors is very high.
Dengue, commonly known as Congo fever, is spread through the bite of an infected Aedes Aegypti mosquito, which usually bites during the day. It occurs in two forms, dengue fever (DF), and dengue hemorrhagic fever (DHF) also called the Crimean-Congo hemorrhagic fever (CCHF), and the infections may cause illness ranging from a mild fever to a severe shock syndrome.