Dengue

The Female mosquito Aedes aegypti feeding on a human host

                           International Dengue Day on 16th May

                                               Dengue Fever/ Breakbone fever/ Dandy fever

 With  the capital  reporting the highest number of Dengue cases this year 2023 in July and the highest for this month since 2018.

How to recognize dengue ? If you live in or recently traveled to an area where dengue fever is prevalent, you could have contracted it if you were bit by an infected mosquito Undifferentiated fever. Mild febrile illness in young children often with respiratory symptoms  Dengue is found in tropical and subtropical climates worldwide, mostly in urban and semi-urban areas. People of all ages who are exposed to infected mosquitoes are at risk for developing dengue fever. The disease occurs most often during the rainy season in tropical countries in Southeast Asia, South Asia and South America, with high numbers of infected mosquitoes. The virus is transmitted to humans through the bites of infected female mosquitoes, though humans are not capable of transmitting the disease and are not contagious.

Cases of vector-borne diseases are usually reported between July and November, sometimes stretching till mid-December. This makes it one of the most common vector borne diseases  worldwide. Rates of dengue increased 30 fold between 1960 and 2010. This increase is believed to be due to a combination of urbanization, population growth, increased international travel, and global warming

Dengue virus has increased dramatically within the last 20 years, becoming one of the worst mosquito-borne human pathogens which tropical countries have to deal with. Current estimates indicate that as many as 390 million infections occur each year, and many dengue infections are increasingly understood to be asymptomatic or subclinical.

                                       

                                           "VECTOR BORN DISEASE"

Introduction

Dengue fever is a mosquito borne tropical disease caused by the dengue virus. 

It is a mosquito-borne, single positive-stranded RNA virus of the family Flaviviridae; genus Flavivirus .

Four serotypes  of the virus have been found which can cause the full spectrum of disease. 

• DENV1 ,
• DENV 2, 
• DENV 3. and 
• DENV 4

                        "DENGUE IS DECLARED NOTIFIABLE DISEASE IN 2018."

A notifiable disease requires government agencies to mandatory report every suspected case of the infection. All districts have also been directed to submit a reports of dengue spread and ensure that  awareness activities are ramped up.

Delhi

 121 cases of Dengue till 28th July 2023 (highest in July 2018) 

In contrast the city logged

23 Dengue cases in July 2022

16 Dengue cases in July 2021

02 Dengue cases in July 2020

Dengue is inflicted in different  forms: 

Dengue fever syndrome : Severe headache, retro orbital pain and intense myalgia and arthralgia (break bone fever) in adults. Usually lasts (4-10) days. May be complicated by bleeding.

Dengue Hemorrhagic fever (DHF) : Acute fever, hemorrhagic tendencies, thrombocytopenia, evidence of plasma leakage. (Hematocrit > 20% above average, plural effusion or ascites.

Dengue shock syndrome (DSS) : All of the above plus , rapid and weak pulse, narrow pulse pressure, colds clammy skin and restlessness.

Severe dengue happens when your blood vessels become damaged and leaky. And the number of clot-forming cells (platelets) in your bloodstream drops. This can lead to shock, internal bleeding, organ failure and even death. Warning signs of severe dengue fever — which is a life-threatening emergency — can develop quickly.

Dengue virus is the cause of dengue fever. It is a (vector) mosquito-borne, single positive-stranded RNA virus of the family Flaviviridae; genus Flavivirus. Four serotypes of the virus have been found, a reported fifth has yet to be confirmed, all of which can cause the full spectrum of disease.

Disease

Common names for dengue fever include Break bone fever, vomiting and dandy fever; dengue hemorrhagic fever and dengue shock syndrome are the severe forms. 

Transmission

Dengue rash blanches when pressed

Dengue virus is primarily transmitted by Aedes aegypti  mosquito. They typically bite during the early morning and in the evening, but they may bite and thus spread infection at any time of day. Humans are the primary host of the virus. An infection can be acquired via a single bite. A female mosquito that takes a blood meal from a person infected with dengue fever, during the initial 2- to 10-day febrile period, becomes itself infected with the virus in the cells lining its gut. About 8–10 days later, the virus spreads to other tissues including the mosquito's salivary glands  and is subsequently released into its saliva. The virus seems to have no detrimental effect on the mosquito, which remains infected for life. Aedes aegypti is particularly involved, as it prefers to lay its eggs in artificial water containers, to live in close proximity to humans, and to feed on people. 

Dengue can also be transmitted via infected blood products and through organ donation. In countries such as Singapore, where dengue is endemic, the risk is estimated to be between 1.6 and 6 per 10,000 transfusions. Vertical transmission  (from mother to child) during pregnancy or at birth has been reported. 

Mechanism

When a mosquito carrying dengue virus bites a person, the virus enters the skin together with the mosquito's saliva. It binds to and enters white blood cells, and reproduces inside the cells while they move throughout the body. The white blood cells respond by producing several signaling proteins, such as cytokines and interferons, which are responsible for many of the symptoms, such as the fever, the flu-like symptoms, and the severe pains. In severe infection, the virus production inside the body is greatly increased, and many more organs (such as the liver and the bone marrow) can be affected. Fluid from the bloodstream leaks through the wall of small blood vessels into body cavities due to capillary permeability.. As a result, less blood circulates in the blood vessels, and the blood pressure becomes so low that it cannot supply sufficient blood to vital organs. Furthermore, dysfunction of the bone marrow due to infection of the stromal cells  leads to reduced numbers of platelets, which are necessary for effective blood clotting; this increases the risk of bleeding, the other major complication of dengue fever.

Viral Replication

Once inside the skin, dengue virus binds to Langerhans cells  (a population of dendritic cells in the skin that identifies pathogens). It seems to be the main point of entry. The dendritic cell moves to the nearest lymph node. . The now mature new viruses are released by exocytosis. They are then able to enter other white blood cells, such as monocyte  and macrophages. 

The initial reaction of infected cells is to produce interferon, a cytokine that raises many defenses against viral infection through the inmates immune response by augmenting the production of a large group of proteins. Some serotypes of the dengue virus appear to have mechanisms to slow down this process. Interferon also activates the adaptive immune system, which leads to the generation of antibodies against the virus as well as that directly attack any cell infected with the virus. Various antibodies are generated; some bind closely to the viral proteins and target them for phagocytosis (ingestion by specialized cells and destruction), but some bind the virus less well and appear instead to deliver the virus into a part of the phagocytes where it is not destroyed but can replicate further.

Incubation Period

Think about the recent travel

(Time between exposure and onset of symptom)

(Time between exposure and onset of symptom) ranges from 3-14 days but most often it is 4 to 7 days after been bitten by an infected mosquito. 

Therefore, travelers returning from endemic areas are unlikely to have dengue fever if symptoms start more than 14 days after arriving home. 

While the period of the illness is 3–7 days

• Recovery 

• 2-7 days

Signs & Symptoms

Recognizing symptoms of dengue fever

People need to watch out for symptoms:
High Fever that last for 5 days, rashes, nasal and gum bleeding bodyache, headache nausea and general fatigue.

• Expect an incubation period of four to seven days. Once you are bitten by a mosquito that is carrying dengue fever, the average time for symptoms to begin is four to seven days.
• While the average incubation period is from of four to seven days, you may experience symptoms as early as three days or as late as two weeks after being bitten.
• Typically, people infected with dengue virus are asymptomatic (80%) or have only mild symptoms such as an uncomplicated fever. 
• Others have more severe illness (5%), and
• In a small proportion it is life-threatening.

Febrile phase

• Sudden onset of fever

Take your temperature. 

• A high fever is the first symptom to appear.
• Fevers with dengue fever are high, ranging from 102°F to 105°F (38.9°C to 40.6°C).
• The high fever lasts for two to seven days, returns to normal or even a little below normal, then can rebound. You may develop a high fever again that can last for several more days.

Watch for Flu like symptoms

• The initial symptoms that develop after the fever begins are generally non-specific, and are described as flu-like in nature.
  • Common symptoms that occur after the fever begins include severe frontal headache, pain behind the eyes, (retro orbital pain)  severe joint and muscle pain, nausea and vomiting, fatigue, and a rash.
  • Dengue fever was once called “break-bone fever” due to the severe pain that is sometimes felt in the joints and muscles.(myalgia & Arthralgia)

                                               

May be complicated by bleeding.

Monitor for symptoms of unusual bleeding. 

Other common symptoms caused by the virus can create hemodynamic changes, or changes that alter the flow of blood in the body.

• Examples of blood flow changes seen with dengue fever include nosebleeds, bleeding from the gums, and areas of bruising.
• Additional symptoms related to changes in blood flow may be evident by reddened areas in the eyes and a sore or inflamed throat.

• Mouth & Nose Bleeding
• Bruising
• Bleeding from gums while brushing
• Vomiting

Evaluate the rash

Dengue rash 

• The initial rash often involves the facial area, and can appear as flushed skin or spotty and reddened areas. The rash does not itch.
• The second rash begins on the trunk area, then spreads to the face, the arms, and the legs. The second rash can last from two to three days.
• In some cases, a rash that is made of small dots, called petechiae, may appear anywhere on the body as the fever subsides. Other rashes that sometimes occur include an itchy rash on the palms of the hands and the soles of the feet.
• Macular or maculopapular rash 
• Skin itching
• Diarrhea

Critical Phase

• Hypotension
• Pleural Effusion
• Ascitis
• Gastrointestinal bleeding

Recovery Phase

• Itching
• Altered level of conciousness
• Seizures
• Slow heart rate

Other symptoms 

• Break Bone Fever
• Severe Headache
• Pain behind the eyes
• Malaise
• Red spots across the body
• Minor hemorrhagic manifestations, including petechiae, ecchymosis, purpura, epistaxis, bleeding gums, hematuria, or a positive tourniquet test result
• Dengue Hemorrhagic fever (severe form of Dengue) can lead to internal bleeding and death.
• Allergic symptoms are one of the core symptoms that are highly associated with dengue severity.

 Children often experience symptoms similar to those of the common cold  and gastroenteritis (vomiting and diarrhea) and have a greater risk of severe complications, though initial symptoms are generally mild but include high fever.

Warning Signs

• Worsening abdominal pain
•  Persistent vomiting
• Liver enlargement
• High Hematocrit (body is making too much of (RBCs) with low platelets
• Lethargy and restlessness
• Red spots or patches on your skin
• Mucosal bleeding such as from your nose or gums, vaginal bleeding in women, or signs of bleeding in your stomach, such as vomiting blood, blood in the poos or black, tarry poos.
• Serosal effusions
• Drowsiness or irritability
• Pale, cold or clammy skin
• Difficulty breathing. 

When Should You Visit A Doctor

• Persistent fever, Frequent vomiting more than three times a day
• Bleeding from nose mouth and gums
• Blood in vomit or stool
• Red spots over the body
• Difficulty in breathing
• Cold or clammy skin.

Complications

In a small proportion of cases, the disease develops into a more severe dengue hemorrhagic fever, resulting in bleeding, low level of blood platelets and blood plasma leakage or into dengue shock syndrome, where dangerously low blood pressure  occurs.

Life Cycle

Primary lifecycle now exclusively involves transmission between humans and Aedes mosquitoes

Spread by the Aedes Aegypti mosquito

Dengue is spread by several species of female mosquitoes  of the Aedes genus, principally Aedes aegypti. The virus has five serotypes infection with one type usually gives lifelong immunity to that type, but only short-term immunity to the others. Subsequent infection with a different type increases the risk of severe complications. A number of tests are available to confirm the diagnosis including detecting antibodies to the virus or its RNA.

The mosquito breeds in clean stagnant water and bites only during the day.

Those who become infected with the virus a second time are at a significantly greater risk of developing severe disease.

                                                          "Asian countries at risk of Dengue".

Severe Disease

Antibody-dependent enhancement, which happens when a person who has been previously infected with dengue gets infected for the second, third, or fourth time. The previous antibodies to the old strain of dengue virus now interfere with the immune response to the current strain, leading paradoxically to more virus entry and uptake

                                                                "If sore throat less chances of Dengue."

Monitoring the patient clinically

• High fever, 
• Headache
• Muscle and joint and bone pain. 
• Fever
• Nausea & vomiting
• Pain in abdomen
• Rashes on abdomen
• Any bleeding from nose or other site
•  In severe cases there is serious bleeding and shock, which can be life threatening.
• BP & Pulse monitoring.

Evaluate the rash

Diagnosis

Diagnosing Dengue Fever

See your doctor. If you have symptoms consistent with dengue fever, see your doctor as soon as possible to determine the diagnosis.

• Blood tests are available that can help your doctor to determine if you have been exposed to dengue fever.
• Your doctor will do blood work that helps to identify the presence of antibodies to dengue fever. It does take several weeks to get the full results of the blood tests.
• Changes in your platelet count can be checked to help verify the diagnosis. People that are infected with dengue fever have lower than normal platelet counts.
• An additional test called the tourniquet test can help with the diagnosis by providing your doctor with information about the condition of your capillaries. This test is not conclusive, but can be used to help with the diagnosis.
• Your signs and symptoms are often enough for your doctor to determine that you have been infected with dengue fever, start supportive treatment, and monitor your progress.

The diagnosis should be considered in anyone who develops a fever within two weeks of being in the tropic and subtropics. It can be difficult to distinguish dengue fever and chikungunya , a similar viral infection that shares many symptoms and occurs in similar parts of the world to dengue. Often, investigations are performed to exclude other conditions that cause similar symptoms, such as malaria, leptospirosis, viral hemorrhagic fever, typhoid fever, meningococcal disease, measles and influenza.. Zika fever also has similar symptoms as dengue.

Consider the geographical limitations of dengue fever. While dengue fever is a global problem, there are areas where the infection is more prevalent, and locations where it has never been reported.

• The areas of the world where you are more likely to be bitten by a mosquito that carries dengue fever include tropical locations such as Puerto Rico, Latin America, Mexico, the Honduras, Southeast Asia, and the Pacific Islands.
• The World Health Organization also identifies other areas that have cases frequently reported including some areas of Africa, South America, Australia, Eastern Mediterranean countries, and island locations in the western Pacific.
• Recent cases have been reported in Europe, France, Croatia, the Madeira islands of Portugal, China, Singapore, India, Costa Rica, and Japan.

Think about your recent travel. If you think you have developed dengue fever, think about the areas you have visited in the past two weeks, or the area where you live.^[18]

• If you reside in the United States, the symptoms you are experiencing are unlikely to be dengue fever, unless you live in California, Texas, or Florida, have visited those states in recent weeks, or have traveled to one of the areas of the globe known to have the mosquitoes that carry dengue fever.

Recognize the mosquito. The mosquitoes that carry dengue fever have unique markings.

• The Aedes aegypti mosquito is small and dark, and has white bands on its legs. It also
  
  
  has a silvery to white pattern on the body that resembles the shape of a musical instrument called a lyre.
• It may be that you remember being bitten by such a mosquito. If you can recall what the mosquito that bit you looks like, then that information can be helpful in confirming your diagnosis.

The diagnosis of dengue is typically made clinically, on the basis of reported symptoms and physical examination; this applies especially in endemic areas.  However, early disease can be difficult to differentiate from other viral infections.

Dengue NS1 Antigen. This is a blood test to detect the dengue virus early in the course of an infection. 

Probable sign

• Fever + two of the following :

#      Nausea and vomiting

#      Rash

#      Generalized Pain

#      Low WBC Count

#      Positive Tourniquet test :The test is part of the WHO algorithm for diagnosis of dengue fever. A blood pressure cuff is applied and inflated to the midpoint between the systolic and diastolic blood pressures for five minutes. The test is positive if there are more than 10 to 20 petechiae per square inch.

OR any Warning Signs:

Warning signs typically occur before the onset of severe dengue.

The diagnosis should be considered in anyone who develops a fever within two weeks of being in the tropic and subtropics. It can be difficult to distinguish dengue fever and chikungunya , a similar viral infection that shares many symptoms and occurs in similar parts of the world to dengue. Often, investigations are performed to exclude other conditions that cause similar symptoms, such as malaria, leptospirosis, viral hemorrhagic fever, typhoid fever, meningococcal disease, measles and influenza.. Zika fever also has similar symptoms as dengue.

The earliest change detectable on laboratory investigations is a 

• low blood cell count, 
• low Platelets, and 
• metabolic acidosis. 

Deranged Liver function test

A moderately elevated level of aminotransferase (AST and ALT)  from the liver is commonly associated with low platelets and white blood cells.

In severe disease, plasma leakage results in hemoconcentration (as indicated by a rising hematocrit) and hypoalbuminuria. Pleural effusion or ascites  can be detected by physical examination when large, but the demonstration of fluid on ultrasound may assist in the early identification of dengue shock syndrome. 

The use of ultrasound is limited by lack of availability in many settings. Dengue shock syndrome is present if pulse pressure  drops to ≤ 20 mm Hg along with peripheral vascular collapse. Peripheral vascular collapse is determined in children via delayed capillary refill , rapid heart rate, or cold extremities. While warning signs are an important aspect for early detection of potential serious disease, the evidence for any specific clinical or laboratory marker is weak.

Doctors can diagnose dengue infection with a blood test A number of tests are available to confirm the diagnosis including detecting antibodies to the virus or its RNA.

• Blood Test
• Complete blood count (CBC)  to know Hb and platelet count. Thrombocytopenia :  Low blood platelet count. High hematocrit :Too many RBCs.
• Liver Function Test
• Laboratory confirmation can be made from a single acute-phase serum specimen obtained early (≤7 days after fever onset) in the illness by detecting viral genomic sequences with rRT-PCR or dengue nonstructural protein 1 (NS1) antigen by immunoassay
•  To check for the virus or antibodies to it. 
• Dengue NS1 Antigen. This is a blood test to detect the dengue virus early in the course of an infection. 
• Nucleic acid amplification tests (NAATs) test
• Immunoglobulin M (IgM) ...
• Immunoglobulin G (IgG) ...
• Dengue RNA PCR test.
• Positive Tourniquet Test : For hemorrhagic manifestation.

Laboratory Diagnosis

Lab Test

Graph of when laboratory tests for dengue fever become positive. Day zero refers to the start of symptoms, 1st refers to in those with a primary infection, and 2nd refers to in those with a secondary infection.

The diagnosis of dengue fever may be confirmed by microbiological laboratory testing. This can be done by virus isolation in cell cultures, nucleic acid detection by PCR viral antigen detection (such as for NSI) or specific antibodies (serology). Virus isolation and nucleic acid detection are more accurate than antigen detection, but these tests are not widely available due to their greater cost. Detection of NS1 during the febrile phase of a primary infection may be greater than 90% sensitive however is only 60–80% in subsequent infections. All tests may be negative in the early stages of the disease. PCR and viral antigen detection are more accurate in the first seven days.

These laboratory tests are only of diagnostic value during the acute phase of the illness with the exception of serology. Tests for dengue virus-specific antibodies, types IgG and IgM, can be useful in confirming a diagnosis in the later stages of the infection. Both IgG and IgM are produced after 5–7 days. The highest levels (titres) of IgM are detected following a primary infection, but IgM is also produced in reinfection. IgM becomes undetectable 30–90 days after a primary infection, but earlier following re-infections. IgG, by contrast, remains detectable for over 60 years and, in the absence of symptoms, is a useful indicator of past infection. After a primary infection, IgG reaches peak levels in the blood after 14–21 days. In subsequent re-infections, levels peak earlier and the titres are usually higher. Both IgG and IgM provide protective immunity to the infecting serotype of the virus.  encephalitis.The detection of IgG alone is not considered diagnostic unless blood samples are collected 14 days apart and a greater than fourfold increase in levels of specific IgG is detected. In a person with symptoms, the detection of IgM is considered diagnostic.

Clinical Course Of Dengue Fever

Clinical Course

The course of infection is divided into three phases: febrile, critical, and recovery.

The febrile phase involves high fever, potentially over 40 °C (104 °F), and is associated with generalized pain and a headache; this usually lasts two to seven days. Nausea and vomiting may also occur. A rash occurs in 50–80% of those with symptoms in the first or second day of symptoms as Flushed skin, or later in the course of illness (days 4–7), as a measles like rash. A rash described as "islands of white in a sea of red" has also been observed. Some petechiae  (small red spots that do not disappear when the skin is pressed, which are caused by broken capillaries) can appear at this point, as may some mild bleeding from the mucous membranes  of the mouth and nose. The fever itself is classically biphasic or saddleback in nature, breaking and then returning for one or two days.

"Islands of white in a sea of red" 

In some people, the disease proceeds to a critical phase as fever resolves. During this period, there is leakage of plasma from the blood vessels, typically lasting one to two days. This may result in fluid accumulation in the chest and abdominal cavity as well as depletion of fluid from the circulation  and decrease blood supply to vital organs  There may also be organ dysfunction and severe bleeding, typically from the gastrointestinal tract. Shock (dengue shock syndrome) and hemorrhage (dengue hemorrhagic fever) occur in less than 5% of all cases of dengue; however, those who have previously been infected with other serotypes of dengue virus ("secondary infection") are at an increased risk. This critical phase, while rare, occurs relatively more commonly in children and young adults.

The recovery phase occurs next, with resorption of the leaked fluid into the bloodstream. This usually lasts two to three days. The improvement is often striking, and can be accompanied with severe itching  and a slow heart rate. Another rash may occur with either a maculopapular  or a vasculitic  appearance, which is followed by peeling of the skin. During this stage, a fluid overload  state may occur; if it affects the brain, , it may cause a reduced level of consciousness or seizures.  A feeling of fatigue may last for weeks in adults.

Spread by the Aedes Aegypti mosquito

• The mosquito breeds in clean stagnant water and bites only during the day.

Risk Factors

Severe disease is more common in babies and young children, and in contrast to many other infections, it is more common in children who are relatively well nourished. Other risk factors for severe disease include female sex, high body mass index  and viral load.  While each serotype can cause the full spectrum of disease, virus strain is a risk factor. Infection with one serotype is thought to produce lifelong immunity to that type, but only short-term protection against the other three. The risk of severe disease from secondary infection increases if someone previously exposed to serotype DENV-1 contracts serotype DENV-2 or DENV-3, or if someone previously exposed to DENV-3 acquires DENV-2. Dengue can be life-threatening in people with chronic diseases such as diabetes and asthma.

Associated problems

Dengue can occasionally affect several other body systems either in isolation or along with the classic dengue symptoms. A decreased level of consciousness occurs in 0.5–6% of severe cases, which is attributable either to inflammation of brain by virus or indirectly as a result of impairment of vital organs, for example, the liver.

Other neurological disorders have been reported in the context of dengue, such as transverse myelitis and Guillain barre' syndrome, infection of heart and acute liver failure  are among the rarer complications.

A pregnant woman who develops dengue is at higher risk of miscarriage, low birth weight  birth, and premature birth.

Classification

The World Health Organisation  2009 classification divides dengue fever into two groups: uncomplicated and severe. 

Severe dengue is defined as that associated with severe bleeding, severe organ dysfunction, or severe plasma leakage while all other cases are uncomplicated. 

The 1997 classification divided dengue into an undifferentiated fever, dengue fever, and dengue hemorrhagic fever. Dengue hemorrhagic fever was subdivided further into grades I–IV. 

Grade I is the presence only of easy bruising or a positive tourniquet test in someone with fever 

Grade II is the presence of spontaneous bleeding into the skin and elsewhere, 

Grade III is the clinical evidence of shock, and 

Grade IV is shock so severe that blood pressure and pulse cannot be detected. Grades III and IV are referred to as "dengue shock syndrome"

Food

Best Foods to Recover From Dengue Fever

• Pomegranate.
• Coconut Water.
• Turmeric.
• Fenugreek (Methi)
• Orange.
• Broccoli.
• Spinach.

Prevention

                                        "PREVENTION IS MOST IMPORTANT."

Avoid mosquitoes. Mosquitoes that carry dengue fever most often feed during the day, usually in the early morning and late afternoon hours.

• Stay indoors during those times, keep the air conditioning on, and keep screen doors and windows closed.
• Travel during the times of day when the mosquitoes are less active.
• Take steps to cover your skin. Wear full-bodied clothing. Even if it is hot, try to wear long sleeves, long pants, socks and shoes, and even work gloves, when you need to be outside during the times of day when the mosquitoes are more active.

• Sleep under mosquito netting.

Bite Prevention

Apply a topical mosquito-repellent product. Products that contain DEET are reported to be effective.

• Other insect-repellent products that may be helpful include those that contain picaridin, oil of lemon eucalyptus.

Inspect your property. Mosquitoes that carry dengue fever are most often found close to dwellings.

• Ensure that there is no accumulation of water in and around their houses and in their neighbourhood.
• They like to breed in water that is held in artificial containers, like gallon drums, flower pots, pet dishes, or old tires.
• Get rid of any standing water containers that are not needed.
• Check for hidden sources of standing water. Clogged drains or gutters, wells, manholes, and septic tanks may have areas of standing water. Clean these areas or repair them so they no longer hold unwanted water.
• Eliminate containers that hold standing water around or near the outside of your home. Clean flower pot saucers, birdbaths, fountains, and pet dishes at least once a week to get rid of any larva.
• Maintain swimming pools and put mosquito-eating fish in small ponds.
• Make sure doors and windows have screens that fit tightly, and all doors and windows close properly.

Window screen

1. Anti larval measures : by adding insecticides  or biological control agents to these areas. With regards to vector control, a number of novel methods have been used to reduce mosquito numbers with some success including the placement of the guppy (Poecilia reticulata) or copepods in standing water to eat the mosquito larvae
2. Generalized spraying with organophosphate or pyrethroid insecticides, while sometimes done, is not thought to be effective.

Vaccine

• On 5 December 2022 the European Medicines agency  approved Qdenga, a live tetravalent attenuated vaccine for adults, adolescents and kids from four years of age. 
• The 2016 vaccine Dengvaxia is only recommended in individuals who have been previously infected, or in populations with a high rate of prior infection by age nine.

Dengue Fever : Aspirin or any pain killer should be avoided because of increased bleeding tendency. Close monitoring for feature of DHF/DSS.

                     "DENGUE DOES NOT HAVE ANY SPECIFIC TREATMENT. Most treatment are symptomatic as it is a self limiting illness"

               "THE ONLY RECOMMENDED DRUG IS PARACETAMOL FOR FEVER."

Treatment

Treatment Symptomatic

There is no specific anti viral therapy for dengue.

There are no approved direct antiviral treatments for Dengue fever. Most

Most cases of dengue fever are mild and go away on their own after about a week.

There are no specific Antiviral drugs for dengue; however, 

• Can be self healing : Condition usually improves over a time without treatment.

Treating Dengue fever

Seek medical attention as soon as possible. While there is no specific treatment for dengue fever, the risks of developing bleeding problems caused by the infection warrant medical care.

• Most people get better in about two weeks with general supportive care.

Follow recommended treatments. The most common methods of treating dengue fever is to take steps to allow your body to heal.

• Get plenty of bed rest.
• Drink lots of fluids.
• Take medicine to control your fever.
• Acetaminophen is recommended in treating your fever and the discomforts caused by dengue fever.

Avoid aspirin products. Due to the risk of bleeding, aspirin products are not to be taken to treat the pain or fever associated with dengue fever.

• Ask your doctor about taking over-the-counter anti-inflammatory agents. Medications like ibuprofen and naproxen can help reduce the fever and treat discomfort.
• In some cases, ibuprofen or naproxen may not be appropriate if you are taking prescription medications that are similar, or if there is a reason to think you may be susceptible to GI bleeding these agents can sometimes cause.

• 

                               Aspirin (or blood thinners)be avoided because of increased bleeding tendency. 
Follow the directions on the label of the product you are using. Do not take more than the amount recommended.

• Talk to your doctor if you are taking any medications for pain, or agents that work to thin your blood, before you take additional over-the-counter products.

• Fluid  Replacement :  Replacing fluids lost through sweating, bleeding, vomiting or diarrhea to treat or prevent dehydration. Maintaining proper fluid balance is important. 
• Once a person tested positive should drink lots of fluids to avoid dehydration.
• Oral Rehydration Therapy : Giving fluid by mouth to treat dehydration caused by Diarrhea. Treatment depends on the symptoms. Those who can drink, are passing urine, have no "warning signs" and are otherwise healthy can be managed at home with daily follow-up and oral rehydration therapy. Coconut water, juice, soups can be given.
• Antiemetic if nausea.
• I.V Fluids : Delivering fluids, medication or blood directly  into a vein.
• Those who have other health problems, have "warning signs", or cannot manage regular follow-up should be cared for in hospital. In those with severe dengue care should be provided in an area where there is access to an intensive care unit.
• Intravenous hydration, if required, is typically only needed for one or two days. 
• In children with shock  due to dengue a rapid dose of 20 mL/kg is reasonable. The rate of fluid administration is then titrated to a urinary output  of 0.5–1 mL/kg/h, 
• Stable vital signs  and normalization of hematocrit. The smallest amount of fluid required to achieve this is recommended.
• Invasive medical procedures such as nasogastric intubation, intramuscular injections  and arterial punctures are avoided, in view of the bleeding risk. Paracetamol  (acetaminophen) is used for fever and discomfort while NSAID  such as ibuprofen and aspirin  are avoided as they might aggravate the risk of bleeding.
• Blood transfusion is initiated early in people presenting with unstable vital signs in the face of a decreasing hematocrit, rather than waiting for the hemoglobin concentration to decrease to some predetermined "transfusion trigger" level. Packed red blood cells or whole blood  are recommended, while platelets and fresh frozen plasma are usually not. There is not enough evidence to determine if corticosteroids  have a positive or negative effect in dengue fever.
• During the recovery phase intravenous fluids are discontinued to prevent a state of fluid overload. If fluid overload occurs and vital signs are stable, stopping further fluid may be all that is needed. If a person is outside of the critical phase, a loop diuretic such as furosemide  may be used to eliminate excess fluid from the circulation.

Expect several weeks to recover. Most people recover from dengue fever in about two weeks.

• Many people, especially adults, continue to feel tired, and somewhat depressed, for several weeks to months following an infection with dengue fever.

Seek emergency medical attention. If your symptoms persist or you develop any signs of bleeding contact your doctor immediately or seek emergency medical care. Some symptoms to watch that are warning signs indicating your body may be having trouble maintaining the integrity of your blood vessels include the following:

• Persistent nausea and vomiting.
• Vomiting up blood or coffee-ground material.
• Blood in your urine.
• Abdominal pain.
• Difficulty breathing.
• Trouble with nosebleeds or bleeding gums.
• Bruising easily.
• Dehydration.
• Decreased blood platelets.
• Emergency medical care will likely result in hospitalization. Once you are hospitalized you will be treated with supportive care that can be life-saving.
• Examples of care that can be provided includes fluid and electrolyte replacement, and treatment or prevention of shock.

Monitor for possible complications

Continue your medical care. Stay in contact with your doctor and report any changes you may experience as you recover from dengue fever, or if symptoms recur or worsen.

• Your doctor will know how to intervene should your condition deteriorate into either dengue hemorrhagic fever or dengue shock syndrome.

Watch closely for persistent symptoms. If symptoms persist beyond seven days, involve problems with continued vomiting, vomiting up blood, severe abdominal pain, difficulty breathing, purplish areas under the skin similar to bruises, and continued problems with nosebleeds or bleeding gums, then you should seek immediate medical attention.

• You may be developing dengue hemorrhagic fever, which is a serious and life-threatening medical condition.
• If you develop those symptoms, then you are in a 24 to 48 hour window where your capillaries, which are the tiniest blood vessels in your body, become more permeable, or leak.
• The leaky capillaries allow fluid to leak from your blood vessels and accumulate in your chest and abdominal cavity, causing conditions medically termed as ascites and pleural effusions.
• Your body is experiencing circulatory system failure which leads to shock. If not immediately reversed, death is likely.

Seek emergency medical attention. If you are showing any signs of dengue hemorrhagic fever or dengue shock syndrome, then you need immediate hospitalization and medical attention. This condition is life-threatening.

• Dengue shock syndrome is recognized by early symptoms that include a decrease in appetite, continued fever, continued vomiting, and persistent symptoms associated with dengue fever. The maximum risk of shock is between the third and seventh day of illness.
• If left untreated, internal hemorrhaging will continue. Symptoms of hemorrhaging include bleeding under the skin, persistent bruising and purplish rashes, worsening of symptoms, abnormal bleeding, cold and clammy arms and legs, and sweating.
• Symptoms like this indicate the person is in, or will quickly be in, a state of medical shock.
• Dengue shock syndrome can be fatal. If the person survives, they may experience brain disease, loss of brain function, liver damage, or seizures.
• Treatment for dengue shock syndrome will include controlling the loss of blood, fluid replacement, attempts to establish a normal blood pressure, oxygen, and possibly a transfusion to restore platelets and provide fresh blood to vital organs.

Prognosis

Most people with dengue recover without any ongoing problems. The risk of death among those with severe dengue is 0.8% to 2.5%, and with adequate treatment this is less than 1%. However, those who develop significantly low blood pressure may have a fatality rate of up to 26%. The risk of death among children less than five years old is four times greater than among those over the age of 10. Elderly people are also at higher risk of a poor outcome.

        https://madhuchhandacdmo.blogspot.com/2021/09/dengue.html