When a 12-year-old boy bleeding from his lungs was admitted to the intensive care unit of Bhatia Hospital in South Mumbai, his doctors were puzzled. The boy had come walking to the hospital with a high-grade fever, which has been a common symptom across Mumbai and many other Indian cities this season. His platelets had dropped to 15,000 units from the normal count of more than 2 lakh units. But in addition to these symptoms, he seemed to develop life-threatening complications within a week of contracting the fever.
“His reports turned out negative for all known infections including malaria and chikungunya,” said Dr Aditya Aggarwal, chest physician at the hospital. “He had low blood platelet count which again is a symptom of dengue infection. We repeated the dengue test; it was negative all three times.”
Aggarwal consulted his colleague and senior paediatrician Dr P Samdani, who also was unable identify the problem. But, both doctors fear that the child might have an infection of the lesser-known Hantavirus.
Hantavirus is a pathogen that causes pulmonary failures that can be fatal and is transmitted through contact with rodents and their urine or droppings. The boy lives in a slum in the southern neighbourhood of Colaba where rodent infestation is not uncommon. Mumbai has never recorded a case of Hantavirus yet.
“His clinical picture fits into the definition of Hantavirus infection,” said Aggarwal. “I don’t have a very good feeling about this case but we are doing our best,” said the doctor.
Explaining the rise in fever cases, Dr DT Mourya in an email to Scroll.in said that vector-borne viral infections, influenza and other respiratory infections show seasonal variations and can manifest as febrile illnesses, which are fevers. “Besides there are other causes of fever," he said. "Despite best efforts and keeping in mind the large population it is very difficult to provide accurate diagnosis in every case.”
But clinicians across the country are coming across patients whose symptoms they are unable to explain. Many patients this year have heard their doctors diagnosing them with “viral fever” from which they seem to recover with pain relievers, fever-reducing drugs, rest and hydration. However, there is a sub-set of patients who develop severe complications like the 12-year-old Mumbai boy.
Dr Om Shrivastav who was consulting on a case of 31-year-old dentist who died at Sir JJ Hospital while being treated for fever recounts that the patients organs seems to have been compromised. “We really don’t know what happened to her,” he said.
The dentist who lived on the hospital campus with her husband had initially tested positive for dengue but when the advance tests did not show the presence of dengue antibodies.
“In 80% of cases where patients develop hemorrhage, it is either the flavivirus or the filovirus,” said Shrivastav. Yellow fever and dengue fever belong to the flavivirus family. These viruses are known to cause encephalitis, which is an inflammation of the brain. Viruses like Ebola belong to the filovirus family and are known to cause severe haemorrhagic fever.
“There was a need to test her serum samples for other viruses which can cause the symptoms she had,” said Shrivastav, who advocates the setting up diagnostic facilities to test the not-so-common viruses.
When a doctor is unable to find the cause of a fever he jots down a phrase in the case notes – "unknown etiology". This could happen If a hospital does not have the appropriate diagnostic facilities.
Dr T Jacob John, vaccinologist and epidemiologist at Christian Medical College in Vellore, recounted a case of a 45-year-old man from Ooty who had developed fever and chills but did not test positive for dengue infection. “The doctors said they did not know the cause for fever,” said John. The patient had delirium and hallucinations when he was admitted at the Christian Medical College hospital . “The doctors recognized that the hallucinations were a result of the hypoxia in the brain," John explained. Hypoxia is a low level of oxygen in the blood supply to the brain. "The patient had also started developing acute respiratory distress syndrome.”
The patient, doctors suspected, was infected with an adenovirus and the tests were performed and throat swab confirmed an abundance of the pathogen, the presence of which could have gone unnoticed in a less equipped hospital.
What then is a mystery fever, that one sees so often in newspaper headlines? “In case of a 'mystery', you are on to a new disease and if infectious, a new agent," said John. "Leptospirosis was rampant in Kerala but unknown to the health ministry, until 1999, when shown with lab tests.”
In the first week of August, the Integrated Disease Surveillance Programme operating under the National Centre for Disease control recorded four fever outbreaks in different parts of the country. More than 150 cases of fever were recorded in four districts in India, according to the surveillance team. “Fever is a symptom and not a disease,” said Dr K Bajan, senior intensivist at PD Hinduja Hospital in Mumbai. “I always tell my colleagues to not stop hunting. We only know one percent of viruses, rest are unknown.”
When the regular viruses are eliminated as causes of infection, doctors presume that some virus has caused the fever.
“In six out of ten children I treat, we cannot really trace the cause for the illness,” said Samdani, adding that there is always this suspicion of mutation of the virus which could be responsible for the varied symptoms.
Officials at National Institute of Virology in Pune said that mutation in viruses are common. As in influenza, the changes known as antigenic drifts are routinely monitored by NIV as the National Influenza Center in collaboration with international partners and there is nothing “unusual” that the rest of the world has not experienced,” said Mourya.
Understanding the dilemma doctors face while treating "unknown" cases, The Indian Society of Critical Care Medicine issued guidelines in 2012 to treat tropical illnesses. The expert committee relied on a syndrome-based approach to manage undifferentiated fevers, fever with low platelets, fever with acute respiratory distress syndrome, fever with encephalopathy and fever with multi-organ dysfunction syndrome. They classified viruses and bacteria that trigger these symptoms in patients to enable a quick diagnosis.
Meanwhile, Aggarwal plans to send the Mumbai boy's samples for Hantavirus testing despite the patient's family being too poor to afford the expensive test. If the test is inconclusive, the child too will be classified as a case of "fever of unknown origin".