Between September 12-15, 2023, the Ministry of Health and Family Welfare in India reported six confirmed cases of the Nipah virus, including two fatalities, in Kerala’s Kozhikode district. All of the affected individuals were males aged between 9 to 45 years. Besides the initial case, which remains a mystery in terms of infection source, the remaining infected individuals were either relatives or hospital contacts of the first patient. By September 27, 2023, contact tracing efforts had tracked 1,288 contacts of the infected individuals, encompassing both high-risk contacts and healthcare practitioners. The quarantine period imposed upon these contacts spanned 21 days.
In relation to testing, there were 387 tests conducted from the onset of the outbreak, leading to six positive cases of Nipah virus. The remaining samples all returned negative results. From September 15, no additional cases were detected. This constitutes the sixth Nipah Virus outbreak in India since 2001. This zoonotic ailment spreads to humans through contact with infected animals such as bats and pigs, or via less common transmission routes such as direct contact with an infected individual.
Patients infected with the Nipah virus experience severe symptoms like acute respiratory infection and potentially fatal encephalitis. To stem or altogether prevent infection, public health officials emphasize the importance of raising public awareness about the risk factors and implementing preventive measures. Case management should primarily concentrate on providing supportive care measures and rigorous support in case of severe respiratory and neurological complications.
In response to the outbreak, a multi-sectorial coordination strategy involving enhanced surveillance, contact tracing, hospital preparedness for case management, and infection control was initiated by both state and national authorities.
The confirmed cases remained clinically stable by September 27, 2023. Kerala’s State Government declared containment zones in nine villages in the Kozhikode district and imposed movement restrictions, social distancing, and mandatory mask-wearing in public areas. Major public events in the district were also prohibited until October 1, 2023. Bordering districts and states were issued alerts for intensified surveillance.
Nipah virus infection rates in infections across Bangladesh, India, Malaysia, and Singapore typically range from 40% to 100%. Currently, there are no vaccines or effective therapies available for this disease. The current outbreak marks the third in Kerala’s Kozhikode district, the fourth in the state of Kerala since 2018, and the sixth in India.
In response to the outbreak, the Department of Health and Family Welfare of the State Government of Kerala collaborated with the Ministry of Health and Family Welfare and its institutions, ICMR, and NIV, Pune, and National Institute of Epidemiology, Chennai. A response plan was initiated entailing quarantine measures, social distancing, mandatory mask-wearing, and comprehensive public and animal disease surveillance.
Managing Nipah virus infections involves providing supportive care to patients suffering from severe respiratory and neurological complications. Reducing the risk of transmission involves boiling freshly collected date palm juice, washing and peeling fruits before consumption, and avoiding areas known for bat roosting. In addition, infected animals should be handled wearing protective clothing, contact with infected pigs should be avoided and samples taken from infected animals should be handled by trained staff in equipped laboratories. Isolation, infection prevention, hand hygiene, and safe burial practices are crucial in healthcare settings to reduce human-to-human transmission.