Abstract
We report here a Nipah virus (NiV) outbreak in Kozhikode district of Kerala state, India, which had caused fatal encephalitis in a 12-year-old boy and the outbreak response, which led to the successful containment of the disease and the related investigations. Quantitative real-time reverse transcription (RT)-PCR, ELISA-based antibody detection, and whole genome sequencing (WGS) were performed to confirm the NiV infection. Contacts of the index case were traced and isolated based on risk categorization. Bats from the areas near the epicenter of the outbreak were sampled for throat swabs, rectal swabs, and blood samples for NiV screening by real-time RT-PCR and anti-NiV bat immunoglobulin G (IgG) ELISA. A plaque reduction neutralization test was performed for the detection of neutralizing antibodies. Nipah viral RNA could be detected from blood, bronchial wash, endotracheal (ET) secretion, and cerebrospinal fluid (CSF) and anti-NiV immunoglobulin M (IgM) antibodies from the serum sample of the index case. Rapid establishment of an onsite NiV diagnostic facility and contact tracing helped in quick containment of the outbreak. NiV sequences retrieved from the clinical specimen of the index case formed a sub-cluster with the earlier reported Nipah I genotype sequences from India with more than 95% similarity. Anti-NiV IgG positivity could be detected in 21% of Pteropus medius (P. medius) and 37.73% of Rousettus leschenaultia (R. leschenaultia). Neutralizing antibodies against NiV could be detected in P. medius. Stringent surveillance and awareness campaigns need to be implemented in the area to reduce human-bat interactions and minimize spillover events, which can lead to sporadic outbreaks of NiV.
Highlights
Nipah virus (NiV) causes a highly lethal disease with acute severe encephalitis and acute respiratory distress syndrome in humans
Nipah virus infection was confirmed by detection of viral RNA in the blood (7 × 105 genome copies/ml), bronchial wash (3.5 × 104 genome copies/ml), ET secretion (1.1 × 107 genome copies/ml), and cerebrospinal fluid (CSF) (3.5 × 104 genome copies/ml) by Quantitative Reverse Transcription (qRT)-PCR and by the detection of anti-Nipah immunoglobulin M (IgM) antibodies in serum sample of the patient
Nipah virus outbreaks have been reported from Malaysia, Singapore, Bangladesh, and India with a range of clinical presentations and case fatality rates of 40–100% [1–6, 8]
Summary
Nipah virus (NiV) causes a highly lethal disease with acute severe encephalitis and acute respiratory distress syndrome in humans. The virus is transmitted to humans by direct contact with the respiratory secretions or body fluids of infected animals, such as bats and pigs, or by consumption of contaminated fruits/palm sap. Both animal-to-human and human-to-human transmission have been documented [1–3]. An outbreak of encephalitis among the human population was observed in Meherpur, Bangladesh in 2001 where the source of infection was traced down to drinking the contaminated raw palm sap or climbing the trees coated with bat excrement [4]. The presence of NiV was detected among Pteropus medius (P. medius) from Maynaguri, West Bengal in 2010 and Cooch Bihar district, West Bengal, and Dhubri district, Assam in 2015 [7, 8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
