What is dengue fever?
Dengue fever is a disease caused by a family of viruses that are transmitted by mosquitoes. It is an acute illness of sudden onset that usually follows a benign course with symptoms such as headache, fever, exhaustion, severe muscle and joint pain, swollen glands (lymphadenopathy), and rash. The presence (the "dengue triad") of fever, rash, and headache (and other pains) is particularly characteristic of dengue. Other signs of dengue fever include bleeding gums, severe pain behind the eyes, and red palms and soles.
Dengue (pronounced DENG-gay) strikes people with low levels of immunity. Because it is caused by one of four serotypes of virus, it is possible to get dengue fever multiple times. However, an attack of dengue produces immunity for a lifetime to that particular serotype to which the patient was exposed.
Dengue goes by other names, including "breakbone" or "dandy fever." Victims of dengue often have contortions due to the intense joint and muscle pain, hence the name breakbone fever. Slaves in the West Indies who contracted dengue were said to have dandy fever because of their postures and gait.
Dengue hemorrhagic fever is a more severe form of the viral illness. Manifestations include headache, fever, rash, and evidence of hemorrhage in the body. Petechiae (small red or purple blisters under the skin), bleeding in the nose or gums, black stools, or easy bruising are all possible signs of hemorrhage. This form of dengue fever can be life-threatening and can progress to the most severe form of the illness, dengue shock syndrome.
Sign & Symptoms
Signs and symptoms of dengue fever vary, depending on the form and severity of the disease.
Dengue fever
With the mild form of the disease, you may experience some or all of these signs and symptoms:
■High fever, up to 105 F (40.6 C)
■A rash over most of your body, which may subside after a couple of days and then reappear
■Severe headache, backache or both
■Pain behind your eyes
■Severe joint and muscle pain
■Nausea and vomiting
Sign and symptoms usually begin about four to seven days after being bitten by a mosquito carrying a dengue virus. Mild dengue fever rarely causes death, and your symptoms will usually subside within a week after starting.
Dengue hemorrhagic fever
More-severe forms of the disease usually begin the same way as the mild form (dengue fever) then become worse after several days.
Dengue hemorrhagic fever — a more severe form of the disease than initial dengue fever — can cause signs and symptoms of dengue fever plus:
■Significant damage to your blood and lymph vessels
■A decrease in the number of blood cells that help your blood clot (platelets)
■Bleeding from the nose and mouth
■Bleeding under the skin, which gives the appearance of bruising
■Death
Dengue shock syndrome — Dengue shock syndrome — the most severe form of the disease — may cause signs and symptoms of mild dengue fever plus:
■Severe abdominal pain
■Frequent vomiting
■Disorientation
■Fluid (plasma) leakage from blood vessels
■Heavy bleeding
■A sudden drop in blood pressure (shock)
■Death
Severe signs and symptoms may appear after your fever has improved. In a small number of cases, people with a severe form of the disease die of it. Modern supportive hospital care decreases this risk.
Causes:
Dengue fever is caused by any one of four dengue viruses spread by the Aedes aegypti mosquito. These mosquitoes thrive in and near human habitations, where they breed in even the cleanest water.
Mosquitoes transmit the virus back and forth between humans. When a mosquito bites a person infected with a dengue virus, the virus enters the mosquito's bloodstream. It then circulates before settling in the salivary glands. When the infected mosquito then bites another person, the virus enters that person's bloodstream, where it may cause the serious illness.
You can become infected with dengue fever more than once. This happens when you're exposed to a different one of the four dengue viruses from the one to which you were previously exposed. Infection a second time is typically what causes the more severe form of the disease — dengue hemorrhagic fever.
How is dengue fever contracted?
The virus is contracted from the bite of a striped Aedes aegypti mosquito that has previously bitten an infected person. The mosquito flourishes during rainy seasons but can breed in water-filled flower pots, plastic bags, and cans year-round. One mosquito bite can inflict the disease.
The virus is not contagious and cannot be spread directly from person to person. There must be a person-to-mosquito-to-another-person pathway.
What is the treatment for dengue fever?
Because dengue fever is caused by a virus, there is no specific medicine or antibiotic to treat it. For typical dengue, the treatment is purely concerned with relief of the symptoms (symptomatic). Rest and fluid intake for adequate hydration is important. Aspirin and nonsteroidal anti-inflammatory drugs should only be taken under a doctor's supervision because of the possibility of worsening hemorrhagic complications. Acetaminophen (Tylenol) and codeine may be given for severe headache and for the joint and muscle pain (myalgia).
What is the prognosis for typical dengue fever?
Typical dengue is fatal in less than 1% of cases. The acute phase of the illness with fever and myalgias lasts about one to two weeks. Convalescence is accompanied by a feeling of weakness (asthenia), and full recovery often takes several weeks.
How can dengue fever be prevented?
The transmission of the virus to mosquitoes must be interrupted to prevent the illness. To this end, patients are kept under mosquito netting until the second bout of fever is over and they are no longer contagious.
The prevention of dengue requires control or eradication of the mosquitoes carrying the virus that causes dengue. In nations plagued by dengue fever, people are urged to empty stagnant water from old tires, trash cans, and flower pots. Governmental initiatives to decrease mosquitoes also help to keep the disease in check but have been poorly effective.
To prevent mosquito bites, wear long pants and long sleeves. For personal protection, use mosquito repellant sprays that contain DEET when visiting places where dengue is endemic. Limiting exposure to mosquitoes by avoiding standing water and staying indoors two hours after sunrise and before sunset will help. The Aedes aegypti mosquito is a daytime biter with peak periods of biting around sunrise and sunset. It may bite at any time of the day and is often hidden inside homes or other dwellings, especially in urban areas.
There is currently no vaccine available for dengue fever. There is a vaccine undergoing clinical trials, but it is too early to tell if it will be safe or effective. Early results of clinical trials show that a vaccine may be available by 2012.
Treatments and drugs
No specific treatment for dengue fever exists.
For a mild form of the disease, your doctor may recommend:
■Drinking plenty of fluids to avoid dehydration from vomiting and high fever.
■Taking acetaminophen (Tylenol, others) to alleviate pain and reduce fever. Don't take aspirin or other nonsteroidal anti-inflammatory drugs, such as ibuprofen (Advil, Motrin, others) and naproxen sodium (Aleve, others). These can increase the risk of bleeding complications.
For a more severe form of the disease, treatment consists of:
■Supportive care in a hospital
■Intravenous (IV) fluid and electrolyte replacement
■Blood pressure monitoring
■Transfusion to replace blood loss
If you have any form of dengue fever, you may also be kept away from mosquitoes, to avoid transmitting the disease to others.
Prevnted
Since cases of dengue appearing in New York are imported, control measures are limited to advising travelers to affected areas to minimize exposure to infected mosquitoes. Use of mosquito netting and repellents may be helpful in minimizing exposure.
REFERENCES:
Canada. Public Health Agency of Canada. "Dengue in South East Asia." Aug. 23, 2007..
"Dengue Fever in Key West." Florida Department of Health..
Switzerland. World Health Organization. "Planning Social Mobilization and Communication for Dengue Fever Prevention and Control.".
Switzerland. World Health Organization. "Vector-Borne Viral Infections.".
United States. Centers for Disease Control and Prevention. "Dengue." May 20, 2010..
United States. Centers for Disease Control and Prevention. "Locally Acquired Dengue -- Key West, Florida, 2009-2010." Morbidity and Mortality Weekly Report 59.19 May 21, 2010: 577-581..
Dengue fever is a disease caused by a family of viruses that are transmitted by mosquitoes. It is an acute illness of sudden onset that usually follows a benign course with symptoms such as headache, fever, exhaustion, severe muscle and joint pain, swollen glands (lymphadenopathy), and rash. The presence (the "dengue triad") of fever, rash, and headache (and other pains) is particularly characteristic of dengue. Other signs of dengue fever include bleeding gums, severe pain behind the eyes, and red palms and soles.
Dengue (pronounced DENG-gay) strikes people with low levels of immunity. Because it is caused by one of four serotypes of virus, it is possible to get dengue fever multiple times. However, an attack of dengue produces immunity for a lifetime to that particular serotype to which the patient was exposed.
Dengue goes by other names, including "breakbone" or "dandy fever." Victims of dengue often have contortions due to the intense joint and muscle pain, hence the name breakbone fever. Slaves in the West Indies who contracted dengue were said to have dandy fever because of their postures and gait.
Dengue hemorrhagic fever is a more severe form of the viral illness. Manifestations include headache, fever, rash, and evidence of hemorrhage in the body. Petechiae (small red or purple blisters under the skin), bleeding in the nose or gums, black stools, or easy bruising are all possible signs of hemorrhage. This form of dengue fever can be life-threatening and can progress to the most severe form of the illness, dengue shock syndrome.
Sign & Symptoms
Signs and symptoms of dengue fever vary, depending on the form and severity of the disease.
Dengue fever
With the mild form of the disease, you may experience some or all of these signs and symptoms:
■High fever, up to 105 F (40.6 C)
■A rash over most of your body, which may subside after a couple of days and then reappear
■Severe headache, backache or both
■Pain behind your eyes
■Severe joint and muscle pain
■Nausea and vomiting
Sign and symptoms usually begin about four to seven days after being bitten by a mosquito carrying a dengue virus. Mild dengue fever rarely causes death, and your symptoms will usually subside within a week after starting.
Dengue hemorrhagic fever
More-severe forms of the disease usually begin the same way as the mild form (dengue fever) then become worse after several days.
Dengue hemorrhagic fever — a more severe form of the disease than initial dengue fever — can cause signs and symptoms of dengue fever plus:
■Significant damage to your blood and lymph vessels
■A decrease in the number of blood cells that help your blood clot (platelets)
■Bleeding from the nose and mouth
■Bleeding under the skin, which gives the appearance of bruising
■Death
Dengue shock syndrome — Dengue shock syndrome — the most severe form of the disease — may cause signs and symptoms of mild dengue fever plus:
■Severe abdominal pain
■Frequent vomiting
■Disorientation
■Fluid (plasma) leakage from blood vessels
■Heavy bleeding
■A sudden drop in blood pressure (shock)
■Death
Severe signs and symptoms may appear after your fever has improved. In a small number of cases, people with a severe form of the disease die of it. Modern supportive hospital care decreases this risk.
Causes:
Dengue fever is caused by any one of four dengue viruses spread by the Aedes aegypti mosquito. These mosquitoes thrive in and near human habitations, where they breed in even the cleanest water.
Mosquitoes transmit the virus back and forth between humans. When a mosquito bites a person infected with a dengue virus, the virus enters the mosquito's bloodstream. It then circulates before settling in the salivary glands. When the infected mosquito then bites another person, the virus enters that person's bloodstream, where it may cause the serious illness.
You can become infected with dengue fever more than once. This happens when you're exposed to a different one of the four dengue viruses from the one to which you were previously exposed. Infection a second time is typically what causes the more severe form of the disease — dengue hemorrhagic fever.
How is dengue fever contracted?
The virus is contracted from the bite of a striped Aedes aegypti mosquito that has previously bitten an infected person. The mosquito flourishes during rainy seasons but can breed in water-filled flower pots, plastic bags, and cans year-round. One mosquito bite can inflict the disease.
The virus is not contagious and cannot be spread directly from person to person. There must be a person-to-mosquito-to-another-person pathway.
What is the treatment for dengue fever?
Because dengue fever is caused by a virus, there is no specific medicine or antibiotic to treat it. For typical dengue, the treatment is purely concerned with relief of the symptoms (symptomatic). Rest and fluid intake for adequate hydration is important. Aspirin and nonsteroidal anti-inflammatory drugs should only be taken under a doctor's supervision because of the possibility of worsening hemorrhagic complications. Acetaminophen (Tylenol) and codeine may be given for severe headache and for the joint and muscle pain (myalgia).
What is the prognosis for typical dengue fever?
Typical dengue is fatal in less than 1% of cases. The acute phase of the illness with fever and myalgias lasts about one to two weeks. Convalescence is accompanied by a feeling of weakness (asthenia), and full recovery often takes several weeks.
How can dengue fever be prevented?
The transmission of the virus to mosquitoes must be interrupted to prevent the illness. To this end, patients are kept under mosquito netting until the second bout of fever is over and they are no longer contagious.
The prevention of dengue requires control or eradication of the mosquitoes carrying the virus that causes dengue. In nations plagued by dengue fever, people are urged to empty stagnant water from old tires, trash cans, and flower pots. Governmental initiatives to decrease mosquitoes also help to keep the disease in check but have been poorly effective.
To prevent mosquito bites, wear long pants and long sleeves. For personal protection, use mosquito repellant sprays that contain DEET when visiting places where dengue is endemic. Limiting exposure to mosquitoes by avoiding standing water and staying indoors two hours after sunrise and before sunset will help. The Aedes aegypti mosquito is a daytime biter with peak periods of biting around sunrise and sunset. It may bite at any time of the day and is often hidden inside homes or other dwellings, especially in urban areas.
There is currently no vaccine available for dengue fever. There is a vaccine undergoing clinical trials, but it is too early to tell if it will be safe or effective. Early results of clinical trials show that a vaccine may be available by 2012.
Treatments and drugs
No specific treatment for dengue fever exists.
For a mild form of the disease, your doctor may recommend:
■Drinking plenty of fluids to avoid dehydration from vomiting and high fever.
■Taking acetaminophen (Tylenol, others) to alleviate pain and reduce fever. Don't take aspirin or other nonsteroidal anti-inflammatory drugs, such as ibuprofen (Advil, Motrin, others) and naproxen sodium (Aleve, others). These can increase the risk of bleeding complications.
For a more severe form of the disease, treatment consists of:
■Supportive care in a hospital
■Intravenous (IV) fluid and electrolyte replacement
■Blood pressure monitoring
■Transfusion to replace blood loss
If you have any form of dengue fever, you may also be kept away from mosquitoes, to avoid transmitting the disease to others.
Prevnted
Since cases of dengue appearing in New York are imported, control measures are limited to advising travelers to affected areas to minimize exposure to infected mosquitoes. Use of mosquito netting and repellents may be helpful in minimizing exposure.
REFERENCES:
Canada. Public Health Agency of Canada. "Dengue in South East Asia." Aug. 23, 2007.
"Dengue Fever in Key West." Florida Department of Health.
Switzerland. World Health Organization. "Planning Social Mobilization and Communication for Dengue Fever Prevention and Control."
Switzerland. World Health Organization. "Vector-Borne Viral Infections."
United States. Centers for Disease Control and Prevention. "Dengue." May 20, 2010.
United States. Centers for Disease Control and Prevention. "Locally Acquired Dengue -- Key West, Florida, 2009-2010." Morbidity and Mortality Weekly Report 59.19 May 21, 2010: 577-581.
