Current Situation
Bangladesh is currently experiencing an outbreak of Nipah virus cases. First reported in the country in 2001, Nipah virus cases have appeared seasonally between December and April since that time. After a successful public health campaign in 2015, there were no reported cases in 2016. However, cases have been on the rise since then, and this current outbreak is trending to surpass 2015 case numbers.
Pathogen and Reservoir
Nipah virus (NiV) is a zoonotic virus of the Paramyxoviridae family. The primary reservoir is fruit bats of the genus Pteropus, locally known as flying foxes.
Fig.1: Photo credit: Dan Arendtsz
Transmission
In Bangladesh, transmission has been primarily associated with consumption of raw date palm sap. The seasonal availability of date palm sap is associated with the annual outbreaks of NiV. Fruit bats drink the sap and urinate, defecate, and occasionally drown in the date palm pots.
In addition to bat-to-human transmission, human-to-human transmission of the virus occurs through close contact and sharing of food.
Clinical Considerations
NiV diagnosis is necessary for determining a patient’s most appropriate treatment. People with the disease symptoms should visit a health facility for blood, urine, and cerebrospinal fluid lab testing. Polymerase chain reaction and serological testing help detect the virus and antibodies against it, respectively (Banerjee et al., 2019). Once detected, supportive care is advisable, including intravenous fluids and respiratory support for patients with severe symptoms. Antiviral therapy may also be considered when necessary. Managing the virus prevents transmission.
Fig. 2: NiV transmission route (Skowron et al., 2022).
Prevention Strategies
Bangladesh’s health department should disseminate the below information to the public to prevent NiV spread and its implications. Firstly, the disease is spread through bat-to-human and human-to-human transmission. The bat-to-human NiV transmission is primarily caused by human consumption of contaminated date palm pap and contact with the animal (Banerjee et al., 2019). The first preventive strategy is avoiding consuming raw date palm sap. As a result, people should boil palm sap before consumption to reduce the risk of contracting NiV, as it is mainly contaminated by fruit bats that urinate and defecate on the collection pots. Being the natural reservoirs of NiV, fruit bats’ saliva may also cause the disease. Consequently, the public should avoid coming in contact with bats, which involves cleaning surfaces where they rest and washing objects or fruits thoroughly before consuming them. Further, it is necessary to cover date palm pots with protective skirts to reduce the exposure of bats to the sap during extraction. Therefore, avoiding contact with fruit bats and preventing them from accessing sap-tapping pots by enclosing them reduces NiV transmission.
Human-to-human NiV transmission occurs through contact with infected people and respiratory secretions, including sneezing and coughing. As a result, it is advisable to avoid close contact with NiV-infected patients. Further, people should prioritize respiratory hygiene, which involves covering one’s mouth and nose when coughing or sneezing (Skowron et al., 2022). People should also wash their hands regularly with soap and avoid sharing food, utensils, or bedding with relatives. Caregivers usually have an enhanced chance of contracting or spreading NiV as they are highly likely to come in contact with infected people. Consequently, they should wear personal protective equipment (PPE), gloves, goggles, and masks when caring for infected people. Avoiding large gatherings is also necessary as crowds enhance the risk of exposure from infected individuals. Hence, prioritizing hygiene and avoiding contact with infected people can reduce human-to-human NiV transmission.
References
Banerjee, S., Gupta, N., Kodan, P., Mittal, A., Ray, Y., Nischal, N., … & Wig, N. (2019). Nipah virus disease: A rare and intractable disease. Intractable & Rare Diseases Research, 8(1), 1–8.
Skowron, K., Bauza-Kaszewska, J., Grudlewska-Buda, K., Wiktorczyk-Kapischke, N., Zacharski, M., Bernaciak, Z., & Gospodarek-Komkowska, E. (2022). Nipah virus–Another threat from the world of zoonotic viruses. Frontiers in Microbiology, 12, 811157.
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