Dengue is transmitted by the bite of an Aedes mosquito infected with any one of the four dengue viruses. It occurs in tropical and sub-tropical areas of the world. Symptoms appear 3—14 days after the infective bite. Dengue fever is a febrile illness that affects infants, young children and adults.
Symptoms range from a mild fever, to incapacitating high fever, with severe headache, pain behind the eyes, muscle and joint pain, and rash. There are no specific antiviral medicines for dengue. It is important to maintain hydration. Use of acetylsalicylic acid (e.g. aspirin) and non steroidal anti-inflammatory drugs (e.g. Ibuprofen) is not recommended.
Dengue haemorrhagic fever (fever, abdominal pain, vomiting, bleeding) is a potentially lethal complication, affecting mainly children. Early clinical diagnosis and careful clinical management by experienced physicians and nurses increase survival of patients.
Severe dengue (previously known as Dengue Haemorrhagic Fever) was first recognized in the 1950s during dengue epidemics in the Philippines and Thailand. Today, severe dengue affects most Asian and Latin American countries and has become a leading cause of hospitalization and death among children in these regions.
Types
There are four distinct, but closely related, serotypes of the virus that cause dengue (DEN-1, DEN-2, DEN-3 and DEN-4). Recovery from infection by one provides lifelong immunity against that particular serotype. However, cross-immunity to the other serotypes after recovery is only partial and temporary. Subsequent infections by other serotypes increase the risk of developing severe dengue.
Global burden of dengue
The transmission has of dengue has grown dramatically around the world in recent decades. Over 2.5 billion people – over 40% of the world’s population – are now at risk from dengue. WHO currently estimates there may be 50–100 million dengue infections worldwide every year. The disease increased predominantly in urban and semi-urban areas and has become a major international public health concern.
Before 1970, only nine countries had experienced severe dengue epidemics. The disease is now endemic in more than 100 countries in Africa, the Americas, the Eastern Mediterranean, South-east Asia and the Western Pacific. The American, South-east Asia and the Western Pacific regions are the most seriously affected.
Background
In 2011 the district health authorities in Islamabad were well aware of the grave situation arising out of the major outbreak in Lahore; under took measures trying to prepare for the prevention and control of Dengue Fever in Islamabad since the beginning of the epidemic. Immediate stringent measures were taken under the supervision of Islamabad Administration with Dr Muhammad Najeeb Durrani the district surveillance coordinator designated by the Chief Commissioner ICT as in-charge of the Dengue Fever Prevention and Control Cell in the District Health Office Islamabad. The cell functioned with the collaborative support of many stake holders to pre-empt the situation mainly to prevent, control and contain the Dengue Fever spread in ICT.
The hospital based surveillance of 2011 played an important role in identifying the characteristics of the disease including its geographical distribution finding of high risk areas and population determinants (gender and age group) to timely develop and institute recommended interventions for containing the disease and mitigate its effects. Thereby in 2012 pre-emptive measures were under taken. There were 84 suspected cases of dengue fever reported in major hospitals of ICT while out of these 9 were found positive.
Local Situation and current strategy to prevent and control
In 2013 upon directions of the Deputy Commissioner/ Director Health, the Dengue fever Surveillance and Response Cell in the Health Department ICT had been re-activated on 10th March 2013. As per rpast practice the Islamabad Health Department having a recent past experience of dealing with the Dengue Fever outbreak has initiated a chain of recommended activities to effectively deal with the disease. Certainly an effort is being made to sustain, continue and strengthen the measures under taken last year for the prevention and control of Dengue Fever in 2013 as well.
- Fumigation and Residual Spray Campaigns: In first phase from May to July this year in 2013 the cell has so far conducted three major rounds of Fumigation and Residual Spray in the rural areas of ICT focusing on schools, public buildings house dwellings and bazaars under the direct supervision of the Deputy Commissioner who officiates as Director Health in Islamabad. The Assistant Commissioners and Magistrates were personally monitoring the campaigns.
- Social Mobilization Campaign: In May 2013 this year Public Awareness campaign was initiated for educating the masses by displaying posters, banners at prominent places and house to house distribution of hand bills through lady Health Workers to educate the masses for taking necessary preventive measures to protect themselves from the disease. Lady Health Workers also delivered health education messages about the disease in the rural areas of Islamabad for providing basic awareness.
- Larvicidal Campaign: In the second phase that was started with the help of Sanitary inspectors and LHWs in August 2013 for adding Chemical Temphos 1% graules are in stagnant water reservoirs and ponds to destroy and eliminate the mosquito breeding cycle thereby killing the mosquito at its larval stage in the current high transmission season. The disease is expected to appear because of the Aedes mosquito breeding in clean water accumulated all over due to stagnant water. The Sanitary Inspectors and the Lady Health Workers have been advised to identify active Breeding sites by making extensive visits in the villages, bazaars and congested areas where the rain water has been collected in the recent rains and
- Quick Solid Waste Disposal: The solid waste that plays an important role in the trash collecting clean water attracting mosquitoes to lay their eggs in large numbers is also to be disposed off quickly on regular basis through motivation and intre-personal communication.
- In the third phase of Hospital based surveillance and epidemic response would be initiated from September onwards that would last till the end of Dengue Fever season in November, active case finding and tracking the patients daily from the addresses obtained from the hospitals of the Islamabad for quick targeted operation through fumigation and residual spray. Patients travel history and contact tracing and identification of high risk areas are also main activities during this third phase.
- Data analysis is the continued activity in the third phase.