Clinical Manifestations of Nipah Virus-Infected Patients Who Presented to the Emergency Department During an Outbreak in Kerala State in India, May 2018

Background: An outbreak of Nipah virus (NiV) disease occurred in the Kozhikode district of Kerala State in India in May 2018. Several cases were treated at the emergency medicine department (ED) of the Government Medical College, Kozhikode (GMCK). The clinical manifestations and outcome of these cases are described.

Methods: The study included 12 cases treated in the ED of GMCK. Detailed clinical examination, laboratory investigations, and molecular testing for etiological diagnosis were performed.

Results: The median age of the patients was 30 years and the male to female ratio was 1.4:1.0. All the cases except the index case contracted the infection from hospitals. The median incubation period was 10 days, and the case fatality ratio was 83.3%. Ten (83.3%) patients had encephalitis and 9 out of 11 patients whose chest X-rays were obtained had bilateral infiltrates. Three patients had bradycardia and intractable hypotension requiring inotropes. Encephalitis, acute respiratory distress syndrome, and myocarditis were the clinical prototypes, but there were large overlaps between these. Ribavirin therapy was given to a subset of the patients. Although there was a 20% reduction in NiV encephalitis cases treated with the drug, the difference was not statistically significant. The outbreak ended soon after the introduction of total isolation of patients and barrier nursing.

Conclusion: The outbreak of NiV disease in Kozhikode in May 2018 presented as encephalitis, acute respiratory distress and myocarditis or combinations of these. The CFR was high. Ribavirin therapy was tried but no evidence for its benefit could be obtained.