Calcutta: Dengue has officially become a dirty word that many government, municipal and private hospitals won't mention even in death certificates.

Terms like "severe fever with thrombocytopenia", "flavivirus" and "capillary leak syndrome" are being used as substitutes for the vector-borne disease in prescriptions, hospital discharge summaries and even death certificates of people with a confirmed dengue diagnosis.

The reason? Denial is easier than taking the sting out of an outbreak increasing in intensity, say public health experts frustrated by the alleged suppression of dengue figures.

The health department estimates the number of people affected by dengue this year to be 20,000-odd, but independent sources in the public health sector believe the figure is much higher.The death toll stands at 40, including at least 10 in the Calcutta Municipal Corporation belt.

"The word 'dengue' is being avoided while writing death certificates, prescriptions and discharge summaries. State-run and municipal hospitals mention the symptoms rather than the diagnosis. If we don't mention the cause of the symptoms, the diagnosis is deemed incomplete," said a well-known doctor in Calcutta.

Private hospitals are just as wary of using the D-Word.

The family of Mita Chaudhuri, a 55-year-old woman from Behala who died on Thursday, said they had to pressure the hospital where she was being treated into mentioning the exact cause of death. Another private hospital did not want to mention dengue in the death certificate of Abirbhab Majumder, 10, his father Abhijit said.

Metro finds out how medical terminology is cloaking the dengue dagger.

Severe fever with thrombocytopenia: The term, according to doctors, denotes high fever with low blood platelet count. The clinical symptoms are fever, vomiting, diarrhoea, multiple organ failure, low platelet count and increased liver enzyme levels.

In dengue, a sharp drop in the patient's blood platelet count is one of the key indicators of the virus being active. The normal platelet count of a healthy individual ranges between 1.5 lakh and 4 lakh per microlitre of blood.

Flavivirus: The four strains of dengue belonging to group called flaviviruses that includes zika, West Nile fever, yellow fever and Japanese encephalitis. Flaviviruses grow within both insects and mammals, infecting humans and domesticated animals.

"Dengue is technically a flavivirus. But it is a generalised term and a way to avoid writing dengue," said a public health expert.

Last month, a doctor in a state-run hospital in Calcutta mentioned "flavivirus" in a dengue patient's prescription. "The doctor thought there might be trouble if he mentioned dengue. He figured that the way out was to mention the group that this virus belongs to," an official said.

Capillary leak syndrome: The term is used to describe a condition when plasma, or the liquid component of blood, escapes the circulatory system through the capillary walls, causing a fall in blood pressure and organ failure. The commonest cause of capillary leak is dengue, a doctor said.