How Kerala’s fight against the Nipah virus has evolved over the years

The lessons from the previous bouts of the infection, coupled with two consecutive years of facing the Covid-19 pandemic in 2020 and 2021, have helped Kerala take the virus head-on in its fourth foray into Kozhikode villages.

The first outbreak in 2018

The outbreak of 2018, which claimed 17 lives out of 18 confirmed cases, had caught the state health department off-guard. The government had no past experience of handling a disease with such a high fatality rate. At the time, the disease was identified only after the virus had already started spreading among human, and claimed a few victims.

What the state then followed was the protocol for Ebola virus disease (EVD), which had been reported mainly in sub-Saharan Africa. Social distancing, contact tracing and isolation became new concepts in Kerala’s society. Images of health workers in PPE kits filled the TV screens for the first time.

Still, during the first outbreak, the health department had only limited knowledge to fall back on to fight the alien virus. But a coordinated effort was launched for the virus’s containment. Apart from the health department, the revenue district administration took up the lead in coordinating with various stakeholders. Route maps of confirmed cases were published to identify contacts and make people self-report. All contacts were put under home quarantine, then unprecedented in Kerala.

At one point in time, 3,000 persons had been under quarantine. A call centre was launched in Kozhikode to give psychological support to all those under quarantine. Isolation wards were opened at the government medical college hospital, which took care of all patients and suspected cases. Several ad-hoc committees were formed. Slowly a procedure was in the making at the war-room of Kozhikode, wards of the medical college hospital and fields of the affected villages.

Developing a protocol

In early June 2019, the health department issued a short Nipah virus infection control guideline. Later in that month, when a case was reported in Ernakulam, the health department, with the support of various other departments, streamlined surveillance activities, contact tracing, quarantine, isolation, and treatment. A medical board, treatment protocol, use of monoclonal antibody protocol and point of care testing were framed.

It was the back-to-back confirmation of Nipah in 2018 and 2019 (then one case in Ernakulam) that forced the health department to work out a systematic approach to deal with any future outbreaks.

Thus, even while tackling the virus in 2019, during its second revisit to Kerala, the health department was already engaged in building structures and processes. A resource group of senior doctors held several brainstorming meetings for preparing guidelines, capacity building, and coordinating the fight against Nipah. At one stage, WHO representatives were also involved in protocol preparation and mock drills were held. The guidelines covered diagnosis, surveillance, treatment and sample collection. These guidelines have been revised twice since they first came up and have been very valuable.

In fact, on January 30, 2020, when Kerala reported the country’s first coronavirus case in Thrissur, the experience of handling Nipah for the past two years held Kerala in good stead. From day one of the coronavirus, the state could roll out its Nipah guidelines, including contact tracking, publication of route map, isolation, treatment and containment at the grassroots level.

An outbreak amidst the pandemic in 2021

In 2020, the state did not report any Nipah case, but the protocol of 2019 was updated and sent across the system. The protocol was again updated in 2021, making it more comprehensive in all aspects, including the treatment algorithm.

In September 2021, when a 12-year-old boy died in Kozhikode due to Nipah, the state was in the trenches in its battle against a second wave of the Covid-19 pandemic. But this helped deal with Nipah as the society at large has been used to quarantining and isolation, and there was a higher degree of compliance among the public with regard to wearing masks.

That year Nipah was confined to a single case as health workers and society were almost insulted due to Covid-19 protocol.

Detection has come a long way since 2018

In 2018, the health department diagnosed people with the Nipah virus only after a few victims died. The state did not have the lab facilities to confirm Nipah. A private hospital in Kozhikode, where a few first cases were treated, sent samples to Manipal Centre for Virus Research (MCVR), which was first to confirm Nipah in Kozhikode. Then it was re-confirmed by the NIV Pune as per the protocol.

During the outbreak of 2019, a POC micro-PCR assay for Nipah detection and ELISA testing facility was started at the govt medical college in Kochi with technical support from NIV, Pune. Since then, government labs have been upgraded in Kerala mainly in the wake of Covid-19.

In 2023, Nipah was detected at the biosafety level-2 lab at the Government Medical College hospital in Kozhikode, but final confirmation came from NIV Pune which has biosafety level-4 lab. In Kozhikode, the government lab could detect the virus in six hours. Apart from the facility in Kozhikode, the state has two other virology labs in Thiruvananthapuram and Alappuzha. Besides, Rajiv Gandhi Centre for Biotechnology in Thiruvananthapuram has launched a biosafety level-2 mobile lab, which would deliver results in three hours.

Managing Nipah in 2023

Currently, Nipah is being managed as per the guidelines issued in 2021. The state health department was alerted by unusual fever cases in Kozhikode in the morning of August 11. The department began collecting fever data and issued orders for surveillance. A local investigation was also launched. Samples were sent for testing on August 11 at the lab in Kozhikode.

But even before receiving confirmation from the lab, the department considered the cases as Nipah and launched control measures accordingly. On August 11 night, Kozhikode lab reported that samples tested positive for the viruses. On that night, samples were rushed to NIV Pune via a flight from Kochi. On August 12 morning, senior officials of the health department, led by Minister Veena George, reached Kozhikode and chalked out an action plan and control measures.

As per the action plan of 2021, a Nipah core committee with 19 multi-discipline teams was formed and a control room was opened. At Kozhikode Medical College, 75 isolation rooms were made ready with plans A, B and C to meet any situation. Contacts of the suspected cases were reviewed in a meeting. Simultaneously, at the villages of the suspected cases, officials of the health department, and presidents of eight panchayats huddled together to finalize the action plan, which would involve multiple departments. On August 12 night when NIV-Pune confirmed Nipah in Kozhikode, the government machinery was already fully operational.

At the control room, which functions round the clock, health workers give psychological support to those under isolation or in-home quarantine through their phones. At villages where positive cases were reported, ASHA workers and grassroots-level health department officials do the leg work mainly mapping the fever cases. Officials of animal husbandry and forest departments are scouting for fruit bats, known to be the reservoirs of the virus.

At nine panchayats, which have been declared as containment zones, respective local self-government bodies have deployed volunteers, rapid response teams, to help people in home quarantine. These volunteers, who had also been on the field during the Covid-19 pandemic, ensured supply and support for those in quarantine. They also help the police and revenue authorities to ensure that people do not move in and out of the containment zones.

Infection control system at hospitals in 2018 and 2023

A striking similarity between the outbreaks of 2018 and 2023, is the role of hospitals in transmission of the virus. Epidemiological linkages of 2018 cases showed most of the cases were infected in healthcare settings at government hospitals/clinics in the late stages of illness.

In hospitals, the infection control system was either not in place or was of a minimal level in 2018 which led to exposure of a large number of health workers. One nurse named Lini Puthussery, then working at the taluk hospital at Perambra, died of an infection while treating a patient.

When Nipah revisited in 2023, it was prima facie found that the index case came into contact with the second victim at a private hospital, leading to the development of a cluster at the latter’s home. Over 150 health workers are under observation.

One of the health workers from a private hospital has tested positive.