How The Kerala Doctors Diagnosed Nipah Virus, Which Had Almost Slipped Undetectd
The earlier Nipah virus strike in Kozhikode was in 2018, claiming 17 lives. In the last 12 days of the virus resurfacing, only two casualties have been reported in the initial stages. However, the possibility of the virus going undetected, disguised as just another fever or death, is shocking. The repercussions of this could have been unthinkable, with several casualties.
The diagnosis could have misplaced the Nipah virus as another cause, because around this time, the symptoms seen in patients differ from what was seen before in 2018, as per medical experts.
Dr. Anoop A. S., a critical care specialist in Aster MIMS, Kozhikode, and an expert in infectious disease in the ICU who was instrumental in diagnosing Nipah then and now, said that encephalitis, or inflammation of the brain, was the symptom observed in 2018, along with neurological symptoms such as seizures, inability to think clearly or concentrate, involuntary shaking of limbs (convulsions), and loss of consciousness.
This time around, the symptoms that have been reported are respiratory-related and progress into bronchopneumonia, constricting the airways, leading to hypoxia or insufficient oxygen. The diagnosis becomes trickier because of the timing. The resurfacing of the Nipah virus coincided with the influenza outbreak, which usually occurs during the monsoon. Fever, cough, cold, and difficulty breathing are common occurrences now, making the diagnosis difficult.
The first patient, this time, passed away because of bronchopneumonia in a private hospital. The hospital missed the case as Nipah; they tested the case only for common influenza and COVID-19 and passed the body to relatives. Eight days after the first patient’s death, another death had occurred. Eight days after the first patient’s death, another death had occurred. The patient reached Aster MIMS for treatment.
Mohammed Ali, 49, from Maruthonkara Grama Panchayat, had passed away, and his two children, a brother-in-law and a relative, were brought in to MIMs with fever and cough. Breathing difficulties were also starting to show. Bronchopneumonia was detected in one of the patients, a child.
The team led by Dr. Anoop, going through patient history, found that their father had passed away due to bronchopneumonia and multiorgan failure just ten days ago. From the doctors who treated Mohammed Ali, the team learnt that he also suffered from slurred speech and double vision and was a bit confused towards the end. By then, the elder child had begun to have seizures. Putting things together, the team realised that there was a cluster of cases before them that needed immediate attention. Without any further delay, the cases were isolated, samples taken, and sent to Pune for further confirmation from the National Institute of Virology (NIV).
“We realised we have a cluster and an index case and the usual symptoms. They are from the same area, which was the epicentre of the Nipah outbreak in 2018,” Dr. Anoop said.
Mohammed’s hometown, Maruthonkara, was only a five-kilometre distance from Janakikadu (literal translation: Janaki Forest), which houses bats of several species and had tested positive for the Nipah virus in 2018. Janakikadu is a woodland, also promoted as an eco-tourist spot, which belonged to a Janaki Amma before it was taken over by the government.
Another patient was brought to Aster MIMS 12 days after Mohammed’s death, a 40-year-old patient from Ayanchery. He complained of cough for three days, then developed low oxygen level in his blood, hypoxaemia, and later died of cardiac arrest after being admitted.
Taking the patient’s history, the doctors found that Ayanchery was 20 km away from Mohammed’s Maruthonkara. The patient had been a caregiver for one of his relatives at the same hospital where Mohammed was treated and eventually died. With this, the health officials were alerted, the body of the patient was not released, and a screen test was undertaken, which tested positive for Nipah. Further, samples for confirmation were sent to Pune’s Institute of Virology.
The virus could have undergone mutations, Virologist Rajendra Pilankatta, also a member of the core committee of experts at the Institute of Advanced Virology, Thiruvananthapuram, said. He said that the Malaysian strain of the virus would not spread from one person to another, unlike the Bangladesh strain, which would spread. Kerala has the Bangladesh strain. Thailand has both strains in their country. He also added that the respiratory problems were seen more in pigs, and encephalitis is seen more in humans.
As a measure to find the origin of the infection, Prof. Pilankatta suggested that a survey of the area would aid in understanding if there were any changes in the biodiversity that were aiding in the spread of the virus. He also stressed the health survey as a measure to combat the spread of the infection. The direct contact of humans with fruit bats could be few, but there could be intermediaries present in the form of pigs, dogs, fruits, and other crops that could spread the infection, he said. Farming on the edges of forest areas in that region was not uncommon.
Nipah is a stable virus that can stay alive in fruit juices for three days and in bat urine for two days. Today, the contacts of the dead, who are suspects, have gone up above 700 people; some places have been declared containment zones, with schools and other institutions shut for the time being. The state has begun to take the necessary measures. It is advised to wear N95 masks, wash hands frequently with soap and water, or use alcohol-based sanitiser, and to keep social distance.
