Dengue Virus

Dengue virus
A TEM micrograph showing Dengue virus virions (the cluster of dark dots near the center).
Virus classification
Group: Group IV ((+)ssRNA) Family: Flaviviridae Genus: Flavivirus Species: Dengue virus

Treatment

The mainstay of treatment is timely supportive therapy to tackle shock due to haemoconcentration and bleeding. Close monitoring of vital signs in critical period (between day 2 to day 7 of fever) is critical. Increased oral fluid intake is recommended to prevent dehydration. Supplementation with intravenous fluids may be necessary to prevent dehydration and significant concentration of the blood if the patient is unable to maintain oral intake. A platelet transfusion is indicated in rare cases if the platelet level drops significantly (below 20,000) or if there is significant bleeding. The presence of melena may indicate internal gastrointestinal bleeding requiring platelet and/or red blood cell transfusion.

Aspirin and non-steroidal anti-inflammatory drugs should be avoided as these drugs may worsen the bleeding tendency associated with some of these infections. Patients may receive paracetamol preparations to deal with these symptoms if dengue is suspected.^[8]

[edit] Traditional and emerging treatments

Emerging evidence suggests that mycophenolic acid and ribavirin inhibit dengue replication. Initial experiments showed a fivefold increase in defective viral RNA production by cells treated with each drug.^[9] In vivo studies, however, have not yet been done. Unlike HIV therapy, lack of adequate global interest and funding greatly hampers the development of treatment regime.

In Brazilian traditional medicine, dengue is treated with cat's claw herb, which is for inflammation and does not prevent dengue.^[10]

In Malaysia, dengue is treated by some using natural medicine. Mas Amirtha and Semalu developed by the Alternative Medicine Research Institute, Center for Asia.^{[citation needed]} The treatment is speculated to be able to arrest and reverse the viral infection and prevent the disease from advancing into a critical stage, though no evidence has yet shown effectiveness. In Philippines dengue patients use tawa-tawa herbs and sweet potato tops juice to increase the platelets counts and revived the patients.

sign and symptoms

The disease manifests as a sudden onset of severe headache, muscle and joint pains (myalgias and arthralgias—severe pain that gives it the nick-name break-bone fever or bonecrusher disease), fever, and rash.^[6] The dengue rash is characteristically bright red petechiae and usually appears first on the lower limbs and the chest; in some patients, it spreads to cover most of the body. There may also be gastritis with some combination of associated abdominal pain, nausea, vomiting, or diarrhea. Some cases develop much milder symptoms which can be misdiagnosed as influenza or other viral infection when no rash is present. Thus travelers from tropical areas may pass on dengue in their home countries inadvertently, having not been properly diagnosed at the height of their illness. Patients with dengue can pass on the infection only through mosquitoes or blood products and only while they are still febrile. The classic dengue fever lasts about six to seven days, with a smaller peak of fever at the trailing end of the disease (the so-called biphasic pattern). Clinically, the platelet count will drop until the patient's temperature is normal. Cases of DHF also show higher fever, variable haemorrhagic phenomena, thrombocytopenia, and haemoconcentration. A small proportion of cases lead to dengue shock syndrome (DSS) which has a high mortality rate. DHF combined with a cirrhotic liver has been suspected in rapid development of hepatocellular carcinoma (HCC). Given that the Dengue virus (DEN) is related to the Hepatitis C virus, this is an avenue for further research as HCC is among the top five cancerous causes of death outside Europe and North America. Normally HCC does not occur in a cirrhotic liver for ten or more years after the cessation of the poisoning agent. DHF patients can develop HCC within one year of cessation of poisoning agent.