National Vector Borne Disease Control Programme (NVBDCP)

MALARIA

In Tamil Nadu, Malaria is confined to some of the Urban, Coastal and Riverine areas such as Corporation of Chennai, Ramanathapuram, Paramakudi, Thoothukudi, Kanyakumari, Krishnagiri, Dharmapuri and Thiruvannamalai.

Malaria screening facility is available in all PHCs and Government hospitals. All fever cases have been screened for malaria by collecting blood smears through Active Case Detection and Passive Case Detection. These slides are being examined within 24 hours and if malaria is confirmed, radical treatment being given within 48 hours as per NVBDCP drug schedule.

Due to intensive control measures carried out by the department, the incidence of malaria has been declined considerably. For the year 2018, malaria incidence (3758 cases) has been decreased when compared with the year 2017 (5444 cases). In TamilNadu, 75% of cases are reported from Chennai.

The goal of 12th five year plan for malaria is to reduce (API) Annual Parasitic Incidence <1 in all districts/state.

DENGUE

Dengue Fever (DF), an outbreak prone viral disease is transmitted by Aedes mosquitoes. DF is characterized by fever, headache, muscle and joint pains, rash, nausea and vomiting. Some infection results in Dengue Haemorrhagic Fever (DHF).DF and DHF are caused by the four dengue viruses DEN 1, 2, 3 and 4, which are closely related antigenically. Infection with one serotype provides lifelong immunity to that virus but not to the others.

Aedes aegypti (Ae aegypti) is the main vector species of DF/DHF in India and is common in most of the urban areas on account of deficient water management, presence of non-degradable tyres and long-lasting plastic containers as well as increasing urban agglomerations and in many instances inability of the community to respond to the need to eliminate mosquito breeding sites. Overhead tanks, ground water storage tanks are usually the primary habitats. Aedes aegypti breeds almost entirely in manmade water receptacles found in and around households, construction sites, and factories. Natural larval habitats are rare, but include tree holes, leaf axles and coconut shells. The population of Ae aegypti fluctuates with rainfall and humidity. During the rainy season, when survival is longer, the risk of virus transmission is greater. The rural spread of Aedes is a relatively recent occurrence associated with increase in breeding sites.

In Tamil Nadu,for diagnosis of the disease, the Government of India has identified 30 Sentinel Surveillance Hospitals including Medical College Hospitals, Zonal Entomological Teams, Institute of Vector Control and Zoonoses, Hosur, and District Headquarters Hospitals-Cuddalore and Ramanathapuram and 1 Apex laboratory (King Institute of Preventive Medicine and Research, Guindy) for diagnosis of Dengue and Chikungunya. The Public Health department in coordination with the local bodies and other departments regularly undertake anti larval measures by source reduction of vector breeding places like artificial containers such as broken utensils, discarded tyres, plastic waste cups and broken bottles for the control of Aedes mosquitoes which spread dengue fever.

The State which had reported 23294 cases in 2017 was able to reduce it to 4486 cases in 2018.The Indian medicines such as Papaya juice extract, Nilavembu and Malaivembu kudineer along with conventional medicine are used for the control of Dengue. Daily surveillance is carried out and the disease is now under control.

CHIKUNGUNYA

Chikungunya is caused by a virus and is transmitted to humans by Aedes mosquitoes. 131 cases were reported during 2017,during the year 2018, 284 Cases are reported. The prevention and control measures against Chikungunya are carried out in an integrated manner with the Dengue control measure.

JAPANESE ENCEPHALITIES CONTROL PROGRAMME

Japanese Encephalitis (JE) is a mosquito borne zoonotic viral disease. The virus is maintained in animals, birds, pigs, which act as the natural hosts. Pigs & wild birds are reservoirs of infection and are called as amplifier hosts in the transmission cycle, while man and horse are dead end hosts. The virus does not cause any disease among its natural hosts and transmission continues through mosquitoes belonging to culex mosquito(vishnui group). Vector mosquito is able to transmit JE virus to a healthy person after biting an infected host with an incubation period ranging from 5 to 14 days.

There are 12 endemic Districts in the State namely Perambalur , Villupuram, Cuddalore, Tiruvannamalai, Virudhunagar, Tiruchirapalli, Thanjavur, Tiruvarur, Madurai, Pudukottai, Karur and Thiruvallur districts. JE Vaccination campaign with SA 14-14-2 type of JE Vaccine is carried out in all these districts in a phased manner since2007 for the children 1-15 years of age .All these districts are fully covered under routine Immunisation as on 2014.

Japanese Encephalitis Control Units at Cuddalore, Villupuram, and Perambalur with Monitoring Unit in Chennai are carrying out Japanese Encephalitis Vector Control activities.

Acute Encephalitis Syndrome (AES) Surveillance is being carried out in District Headquarters Hospitals, Medical College Hospitals and major private hospitals. Serum samples are taken from the AES cases for diagnosis of JE. Lab diagnosis is done in 7 Sentinel Surveillance Hospitals which includes King Institute of Preventive Medicine and six Medical College Hospitals. In 2017, 127 JE cases with 2 deaths and in 2018, 147 cases with nil deaths.

Considering the complexity of JE/AES (Acute Encephalitis Syndrome) problem ,a comprehensive National Programme on Prevention and Control of JE/AES with the participation of concerned Ministries/ Departments has been launched. The goal of the Programme is to reduce morbidity, mortality and disability in children due to JE/AES. Tamil Nadu is one of the five States where this programme has been started.

JE vector monitoring is being carried out regularly in the endemic districts. Fogging operation is being carried out in villages where suspected JE cases are reported.

FILARIA

The National Filaria Control Programme is being implemented in Tamil Nadu since 1957. There are 14 filaria endemic districts namely, Kancheepuram, Thiruvallur, Vellore ,Cuddalore, Villupuram, Trichy, Perambalur, Pudukottai, Thiruvannamalai, Thanjavur, Thiruvarur, Ariyalur, Nagapattinam , Kanniyakumari in the State.Under Filaria Control Programme , 25 Filaria Control Units have been established which carry out disease control activities are carried out in 43 urban areas through Night Clinics (44) and Filaria and Malaria Clinics(42) and conduct anti larval operation.Larvicides and tablets (Di-ethyl Carbamazine (DEC) and Albendozole ) are procured from GoI funds. The entire operational cost is met by the State Government.

Single dose Mass DEC Drug Administration programme (MDA) is being carried out from 1997-98 in all endemic districts. The Mass Drug Administration programme was conducted in 14 endemic districts with the objective to bring down the mf rate to less than 1, namely, Kancheepuram, Thiruvallur, Cuddalore, Villupuram, Trichy, Perambalur, Pudukottai, Thiruvannamalai, Thanjavur, Thiruvarur, Ariyalur, Kanyakumari, Nagapattinam, Vellore and certain villages of Tirunelveli, Thoothukudi, Karur, Krishnagiri, Virudhunagar and Madurai and 64 wards in Chennai Corporation till 2012. In 2013, MDA was conducted in Vellore, Thiruvannamalai, Perambalur and Virudhunagar districts where the mf rate is more than 1. It is proposed to conduct MDA only in Tiruvannamalai & Cuddalore District during 2014.

In the districts with mf rate less than 1, Transmission Assessment Survey (TAS) using Immuno Chromatography Test Cards to detect the antigenemia. Based on MDA will stopped or continued. So far Thiruvarur (2012), Perambalur & Ariyalur (2013) has completed TAS. It is also planned to conduct TAS in remaining district in phased manner.

Govt.of Tamilnadu is giving financial support of Rs.400/- for LF Grade IV patients. Morbidity management kit is issued to LF patients for self care practice. Hydroceletomy are being conducted.

LEPTOSPIROSIS

Leptospirosis being one of the reemerging infection of zoonotic origin. It requires timely diagnosis, treatment and control measures. Leptospirosis is being reported from most of the districts of TamilNadu. To strengthen the surveillance system and for early diagnosis of leptospirosis, 7 leptospirosis clinics are functioning in Thiruvallur and Madurai Districts. For screening of fever cases, IgM ELISA kits are procured and supplied to the 9 Zonal Entomological Teams and Institute of Vector Control & Zoonoses, Hosur. Outbreak investigation of leptospirosis is carried out by Zonal Entomological Teams and IVCZ, Hosur. 693 leptospirosis cases have been reported during the year 2013 and 2 deaths has occurred.