The World Health Organization (WHO) defines dengue as a “viral infection transmitted to humans through the bite of infected mosquitoes”. It states that the primary vector that transmits the disease are the Aedes aegypti mosquitoes.
According to the global health body, while severe dengue is a leading cause of “serious illness and death” in some Asian and Latin American countries, there is no “specific treatment for dengue/severe dengue”.
“Early detection of disease progression associated with severe dengue, and access to proper medical care lowers fatality rates of severe dengue to below 1 per cent,” the WHO adds.
Dr Farah Adam Mukadam, family physician at Kauvery Hospital, Electronic City (Bengaluru) says the Aedes mosquito “has a rather emboldening nickname — the tiger mosquito”.
“Striped and buzzing around during the day (and not at night) is what makes it different from the malaria mosquito. The dengue virus lives in the salivary glands of the Aedes mosquito and is transferred to the body of the victim when the mosquito bites,” she states.
According to the doctor, the dengue virus starts multiplying in the human body and one of the first symptoms is fever. The illness, she states, is divided into three stages: fever stage (medically called the ‘febrile’ stage); critical stage (complications can happen); convalescent stage (recovery time).
“The classical symptom which a doctor looks for in a fever patient is eye pain and joint pains,” says the expert, adding that the dengue virus afflicts ‘arthralgia’ and not ‘arthritis’.
“Arthralgia is joint pain and inflammation and is temporary in nature — it is like the virus has just licked the joint. Arthritis is a longer effect of the Chikungunya virus (this virus ‘bites’ the joint) and needs more time to recover.”
Dr Mukadam adds that after the joint pain sets in, the next thing to happen is liver inflammation, whose symptoms include loss of appetite, nausea and vomiting. In milder cases, it can be controlled with “simple anti-gastritis meds”.
“Unless the patient is vomiting non stop — which is not letting them keep even the meds down — we do not admit at this stage. It is at this stage that the infection can take a turn for the worse. If the patient’s vomiting has not stopped, admission to the hospital may be necessary for IV fluids,” the doctor warns.
She states that a patient presenting with fever even in a dengue-endemic area is not tested till 48 hours of fever having been passed. “Their blood is drawn to confirm if it’s a dengue. Urine routine examination, liver enzymes and complete blood count are done. Blood cells in the urine, highly elevated liver enzymes and a plummeting platelet count point towards the infection taking a dangerous turn.”
It should be noted that the “hallmark of this viral infection” is the dropping platelet count. “Platelets are the cells present in our bloodstream that help with the function of clotting. Serial platelet counts are done in dengue patients to assess which direction the counts are heading. A serial lowering count is observed and if the count drops below 20,000 cells/ml, the patient needs to be admitted.”
The doctor also says one must look for signs of bleeding. “Spontaneous nose or gum bleeds, tiny dots on the skin — which means blood in the skin (medically called ‘petechiae’) — or an unexpected vaginal bleed are all to be watched out for. A simple pinkish itchy rash is seen in the recovery phase of the infection, but it is not to be confused with petechiae,” she explains.
Dr Mukadam cautions that there are changes happening in the blood circulation, too. “Fever accompanied with low blood pressure, cold feet and fingertips or seizures require urgent management. Prolonged low blood circulation can lead to ‘shock’ that entails low blood supply to vital organs like the brain, kidneys and heart. It could even lead to coma and death.”
She added that low blood pressure with a rapid and weak pulse needs close observation, since these are warning signs of a “failing circulation”. “The recovery period can be unremarkable with post-viral fatigue or as serious as fluid accumulation around the lungs — a condition known as ‘pulmonary edema’.”