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.

By World Health Organization

article460BY :AMANTHA PERERA, JULY 29, 2017

Colombo. Eight years after the end of a bloody civil conflict, Sri Lanka is on a war footing once again. This time all available resources have been pitched against a pesky and increasingly deadly foe: the dengue-carrying mosquito.

In the first seven months of this year more than 109,000 cases of dengue infection have been reported in Sri Lanka, according to the Ministry of Health, with over 300 deaths, an all-time high.

The infection rate is more than four times the annual average recorded since 2010.

Local and international experts warn that changing rainfall patterns that bring intense but short bursts of rain, combined with a lack of measures to limit mosquito breeding areas and the possible emergence of a new strain of the dengue virus, have made the island’s densely populated urban areas high-risk zones.

The outbreak follows heavy rains and flooding that have affected 600,000 people across 15 of Sri Lanka's 25 districts, according to a situation report issued by the World Health Organization on July 24.

Since May, when over 400mm of rain fell within two days, more than 64,000 infections have been reported, the bulk from Western Province, where over a quarter of the country’s population of 20 million live.

Dengue is a mosquito-borne viral infection that in unusual cases can be fatal. WHO and Sri Lankan health authorities have warned patients to take an antigen test to detect possible dengue if they have a fever that lasts for more than a day.

There is no cure for dengue, and medical experts recommend early detection and expert care as the most effective way of overcoming an infection.

Fast Diagnosis

Ranil Peiris from Kelaniya in Western Province, whose 6-year-old son contracted dengue in June, said it was early detection that helped them.

When the boy had a persistent fever, their doctor recommended the antigen test, and based on the results Peiris's son was admitted to the Ragama National Hospital, just north of the capital, Colombo.

"The ward was full of patients and there were more waiting to get admitted. The doctors would only admit the serious cases. But what we noticed was that the medical staff was extremely capable. They knew exactly what to do," Peiris said.

With infections rising, the government has imposed a standard fee of 1,000 Sri Lankan rupees ($7) for the antigen test, specifying that results should be provided within two hours to speed up medical care.

But experts say that ridding vulnerable areas of mosquitoes is as important as detecting and treating dengue cases.

Heavy rains, combined with a lack of adequate drainage, have caused a massive increase in the number of pools of stagnant water and the amount of rain-soaked waste – ideal breeding grounds for mosquitoes, said Novil Wijesekara, a consultant health official with the Sri Lanka Red Cross Society.

Wijesekara warned that, as long as the rains persist, the threat of infections remains high.

Furthermore, Wijesekara said, Red Cross crews have discovered that locations cleared during previous anti-dengue cleanup operations had once again become breeding areas because mosquito larvae had survived and become active with the rains.

"Larvae would have been dormant when there was no rain, and with the rain the dormant larvae developed into adults," agreed Faseeha Noordeen, professor of microbiology at the state university in Peradeniya.

"More vigilance is essential during the dry season to make sure that possible breeding areas are checked and cleaned regularly," Noorden said.

New Type of Dengue

Her research has found that a new variant of the dengue virus, known as DENV-2 has become more dominant during the current outbreak.

"When the serotype shift occurred in late 2015 or early 2016 from DENV-1 to DENV-2, many in the population met this new serotype for the very first time," said Noorden.

"The majority in the population was not immune to this new serotype. The serotype shift is the major reason for the recent outbreaks with the unprecedented number of cases."

The Red Cross's Wijesekara agreed that the emergence of the new variant was a factor in the growth in dengue cases.

The Sri Lankan government has launched a nationwide campaign to stem the epidemic, even co-opting the armed forces to help with cleanup operations, but experts say it’s too little too late.

They recommend that proactive eradication measures should be implemented throughout the year, not just when the number of infections increases.

Noorden said that public dengue eradication campaigns should be synchronized with the epidemic patterns that have become apparent, such as spikes in infections following heavy rains.

She advised the government to consult weather forecasts and launch eradication measures before heavy rains and continue throughout them.

Beyond cleaning areas up, improving drainage to avoid stagnant water is also key, Wijesekara said.

The government says it is taking all possible measures to stem the epidemic.

"It is the highest priority of the government right now and no effort will spared to get rid of dengue. We will make sure that we do not face this kind of a situation again," Health Minister Rajitha Senarathana said in a telephone interview.

He added that in early August the government will introduce a new action plan prepared by WHO consultants and that he expected infections to slow down soon. Details of the plan are not yet publicly available.

The Sri Lanka Red Cross Society has had 300 volunteers working on dengue eradication. The organisation also is beginning a six-month program involving many of its 6,000 volunteers in cleanup and in raising the population’s awareness of dengue risks, according to an action plan issued on Jul. 23.


Article source- https://jakartaglobe.id


Dengue Fever Symptoms

Dengue Haemorrhagic Fever is a mosquito-borne viral infection endemic in the tropical and sub-tropical regions. The female Ae.aegypti (the most important vector) mosquito is semi-domesticated, preferring to lay its eggs in man-made water containers, resting indoors and feeding in the early morning or late afternoon. There are 4 serotypes of Dengue virus. Dengue usually occurs as epidemics in Sri Lanka following monsoon seasons.
According to data from epidemiology unit of Sri Lanka, the number of total cases recorded for year 2009 is 32713. Most affected district was Kandy. Colombo, Gampaha and Kaluthara districts which have been susceptible in the past have also recorded a high rate of infection and deaths.
Dengue virus; There are 4 serotypes of the single-stranded RNA virus (flaviviridae).
Patients become infected once bitten by mosquitos. The virus passes to lymph nodes and replicates which is followed by spread to the circulation and other tissues. It is thought that infection with a secondary serotype is what leads to severe haemorrhagic disease.
Disease varies in severity
- Incubation period is 2-7 days.
- All haemorrhagic fever syndromes begin with abrupt onset of fever (39.5–41ºC) and myalgia.
- Fever is often biphasic with two peaks.
- Fever is associated with frontal or retro-orbital headache lasting 1–7 days, accompanied by generalised macular, blanching rash.
- Initial rash usually fades after 1–2 days.
- Symptoms regress for a day or two then rash reappears in maculopapular, morbilliform pattern, sparing palms and soles of feet. Fever recurs but not as high. There may be desquamation.
- DF cases experience severe bony and myalgic pain in legs, joints and lower back which may last for weeks (hence breakbone fever).
- Nausea, vomiting, cutaneous hyperaesthesia, taste disturbance and anorexia are common.
- Abdominal pain may occur and if severe suggests DHF pattern.The signs of dengue fever/ Dengue haemorrhagic fever are- High fever, rash, hypotension and narrow pulse pressure, poor capillary refill.
- There may be hepatomegaly and lymphadenopathy.
- A tourniquet placed on an arm may induce petechiae in early DHF cases. DHF sufferers exhibit a bleeding tendency as evidenced by petechiae, purpura, epistaxis, gum bleeding, GI haemorrhage and menorrhagia. There may be pleural effusion, ascites and pericarditis due to plasma leakage.
- Petechiae are best visualised in the axillae.
- Flushing of head and neck.
- Tender muscles on palpation.
- Periorbital oedema and proteinuria may be present.
- Maculopathy and retinal haemorrhages may also occur.
- DSS pattern cases progress through DHF until profound shock due to severe hypotension is present.
- CNS involvement e.g. encephalopathy, coma, convulsions.

- Hepatic failure: Means failure of the liver
- Encephalopathy: Means damage to the brain causing fits, loss of consciousness and confusion- Myocarditis – Inflamation of heart muscles
- Disseminated intravascular coagulation - Damage to blood vessels and blood cells causing problematic bleeding and clottingDengue can cause death
- FBC - low platelets and high packed cell volume if haemoconcentrated. Usually white cell count will fall
- Infection may be confirmed by isolation of virus in serum and detection of IgM and IgG antibodies for Dengue by ELISA, monoclonal antibody or haemagglutination
- Molecular diagnostic methods such as reverse-transcriptase-PCR are increasingly being used.
- Chest X-ray may show pleural effusion.
- Bed rest
- Nutritious diet and lot of liquids, But avoid red and brown foods and drinks like coffee, chocolate, grapes etc as it may misinterpret vomiting as blood stained vomitus.
- Fever control with paracetamol, tepid sponging and fans. Aspirin should be avoided.
- Need to seek advice from a qualified medical practitioner if fever lasts for more than 2 days
- Hospital managemnt includes intravenous fluid resuscitation with close monitoring. Haemorrhage and shock will require Fresh Frozen Plasma, platelets and blood. Intensive management with inotropes of the shock syndrome may be required in severe DHF/DSS cases.
- Vaccines are being researched
- Anti-mosquito public health measures such as reducing breeding sites ( flower pots, fish tanks,tires, coconut shells, tins, water collecting plants, gutters which can collect water) and good sewage management
- Insecticides to destroy the larvae
- Mosquito nets can be used during day time as the Aedes mosquitoes is day-biting.
- Mosquita repellents
- There is a bacteria called Bacillus thuringiensis which destroy the mosquito larvea

Featured Posts

Recent Posts

Show Panel