DR. SRIKANT SHARMA,
Dengue fever is a viral fever symptom like disease, especially with severe joints and muscle pain, hence also previously known as break bone fever. This Dengue fever is primarily known for 200 years, to health experts. Dengue is fast emerging pandemic prone viral disease affecting primarily Asian and Latin American countries.
Over the past 20-25 years, next to disease related to diarrhea and respiratory infection, dengue has become one of the leading causes for hospitalization and deaths among children. Today dengue is one of the most important arthropod borne viral disease in humans, as far as mortality and morbidity is concerned. It is also the number one killer worldwide amongst viral infection. Among travelers dengue is the second most diagnosed caused of fever after malaria. In 2015, Delhi, India, recorded its worst outbreak since 2006 with over 15,000 cases. Hence knowledge of prevention is needed for children in their school syllabus.
Aedes Aegypti and Aedes Albopictus, mosquitoes are responsible for dengue transmission.
In India A. Aegyptiis the most common mosquito. A. Albopictus is a secondary dengue vector in Asia, has spread to North America and more than 25 countries in the European region, largely due to international trade in used Tyres (breeding habitat) and other goods (eg- lucky bamboo). A. Albopictusis highly adaptive and therefore can: survive in cooler temperature. It can tolerate low temperature hibernate and can shelter in micro habitat.
Dengue is transmitted by the bite of Aedes mosquito that attacks especially at dawn and dusk. Only female mosquitoes transmit the virus, and are active in day time. They prefer to stay in dark places like under the table or behind screen etc. Most bites are below the knee and below elbow.
Aedes mosquitoes cannot breed once the temperature goes below 16C for 3 days consecutively. These mosquitoes are active between Aug. to Oct. Hence, the peak period for dengue cases. Rarely transmission has been witnessed in winters, this may be because of uses of air-conditioning to keep temperature above 16C.
The dengue Virus seems to have no detrimental effect on the mosquitoes, but mosquitoes remain infected for life long.Aedes transmits this virus by feeding preferably human rather than other vertebrate.
Dengue is found where Aedes mosquitoes are present. Aedes mosquitoes are found in tropical and subtropical regions. These mosquitoes cannot fly more than 200 meters horizontally and 1000 meters vertically. But now Dengue has become a global problem and is common in > 110 countries. Each year 10,000 to 25,000 die and between 50 and 528 million people get infected and 2.5 Billion people (2/5th world population) at risk of infection. Delhi, where 10,000 cases and 400 deaths were reported in 1996, which was the first major outbreak in Delhi.
After virus is transmitted to humans, it takes 4 – 10 days to produce symptoms. Infection is transmitted by patients for 4 -5 days (maximum 12 days) via mosquitoes, after first symptoms appear.
June 15 is observed internationally as anti-dengue day. Idea was to increase awareness about dengue, mobilize resources for its prevention and control, and to demonstrate the Asian region’s commitment towards tackling the disease.
Dr. Srikant Sharma, MBBS, MD (Medicine), Senior Consultant medicine, MCKR Hospital, New Delhi, published many national and international papers and chapters in books.
Dr. Sharma, an eminent medicine specialist with decades of experience in health care management with a holistic perspective having researched on sub systems of health care presents his article on Dengue Awareness – Key to Dengue Prevention.
Dengue is a Notifiable disease in India. The notification stipulates better case management and reduce transmission of disease. Health care providers should notify every case to the District Medical and Health Officer and the Municipal Health Officer daily. An appropriate strategy for control of mosquitoes breeding could then be devised. Dengue prone states like Maharashtra, Kerala, Tamil Nadu, Gujarat, Madhya Pradesh, and Delhi may benefit from the move if it is enforce properly. Since it’s primarily, a preventable disease, hence notification may help in reducing the disease propagation, if proper and prompt action is initiated.
Dengue warning signs are Abdominal pain, Persistent vomiting, Fluid accumulation in lung/ abdomen/ skin, Mucosal bleeding, Lethargy/ Restlessness, Liver enlargement, rapid decline in platelet count).
If dengue warning signs present and/or dengue is with co- existing morbid diseases(Diabetes, Heart disease, Kidney disease, Transplant patients, Immuno suppressed patients, HIV patients, patients on steroids, Bronchial Asthma, severe Trauma, Peptic ulcers), patients should be admitted. Patients on Aspirin or on Anticoagulant and obese or infant (< 1 years age) also are high risk dengue patients.
Approximately 1 in every 13 patients of dengue reports to doctor. Mortality in Dengue fever is 1-2 %, in DHF (Dengue Hemorrhagic fever) is 10% and in DSS (Dengue Shock Syndrome) is 12-44% in various studies.
Death is because of low blood pressure, major bleeding or multi- organ failure.
Prevention of Dengue fever is by reducing mosquitoes habitat and limiting exposures to bites:
- Use mosquitoes repellent (DEET & Picaridin) spray or lotion on body. Mosquitoes repellent protects only for 4 hours but not the whole day. Electrical insecticide (repellent treated pads) devices in enclosed areas may be beneficial. Spraying with organophosphate or Pyrethroid insecticides, is not thought to be effective.
- Stay in well screened area.
- Wear full sleeves Pajamas, shocks during day time.
- Take sufficient fluids to avoid dehydration.
- Dengue patients should not go to school,office or crowded public places.
- Avoid leaving any container with standing water, where mosquitoes can breed.
- Put 1 tablespoon of petrol / oil over standing water or cooler to deprive mosquitoes from oxygen which is required for their survival.
- Covering, emptying and cleaning of domestic water storage containers on a weekly basis.
Due to this disease patients immunity goes down. Hence patient should not mix with other patients who are suffering from fever, cough, active tuberculosis, infectious diseases. Follow healthy balanced diet with high protein, high red and yellow fruits, and high mineral, high dry fruits diets. They should do daily exercise (150 minutes in at least 5 divided days per week) or Yoga. Avoid pollution, smoking, alcohol. Take a good sleep, and last but not least, positive thinking which helps to modify the good immunity of the person
Placement of guppy or Gambusia fish or copepods in standing water to eat the mosquito larvae. There are also trial with genetically modified male A. Aegyptus that after release into the wild mate with females, and render their offspring unable to fly.
Research is also going on, to infect the mosquito population with Wolbachia bacteria, which makes the mosquito partially resistant to dengue virus.