A new study has confirmed the transfer of humoral immunity against Nipah Virus (NiV) from mother to newborn baby for the first time.
A novel finding on the vertical transfer of immune properties by icddr,b scientists, and partners was recently published in the journal of Tropical Medicine and Infectious Disease.
This will also be a reference for vaccine recommendations for pregnant and young women against the Nipa Virus, said the study's lead researcher, Assistant Scientist and Deputy Project Coordinator for Emerging Infections and Infectious Diseases Division at icddr,b Dr Syed Moinuddin Satter.
NiV is a zoonotic virus (it is transmitted from animals to humans) and can also be transmitted through foods contaminated by animals or directly between people. Fruit bats from the genus Pteropus are its natural reservoir, and NiV is one of the present time's fatal emerging pathogens.
According to the World Health Organisation (WHO), the mortality rate for NiV is estimated at 40 per cent to 75 per cent, and in Bangladesh, it is about 71 per cent.
The survivors of NiV infection suffer from severe neurological complications. Besides, there is a high chance that these symptoms worsen progressively when a survivor becomes pregnant and approaches the term.
In January 2020, a baby girl aged below five years and her mother from Faridpur district were infected with NiV who consumed raw date palm sap. Unfortunately, the daughter passed away and the mother survived with significant residual neurological impairment.
The mother received medical attention in November 2021 and was under thorough antenatal follow-up by the National Nipah surveillance authority. A healthy male baby was born in August last year. As part of the follow-up, specimens were collected and tested for NiV infection at the reference laboratory to exclude vertical transmission.
Although tested negative for anti-Nipah IgM and PCR for NiV, a high titer of anti-Nipah IgG was observed. The transfer of humoral immunity against NiV from the mother to the neonate was confirmed for the first time, the study shows.
Dr Syed Moinuddin said, "To the best of our knowledge, this finding is the first to report the vertical transfer of NiV-specific immune properties. It warrants further exploration of its effectiveness in virus neutralisation and its potential to protect newborns."
icddr,b in partnership with the Government of Bangladesh, has been running the world's longest Nipah virus surveillance to detect Nipah Virus outbreaks, understand the disease transmission, and find new knowledge and insights that can help develop therapeutics and vaccines against this deadly infection, said Dr Tahmeed Ahmed, executive director at icddr,b.
"The effort has been rewarding, and I hope we will soon have effective preventive measures and treatments, and be able to save lives."
To warn people from consuming raw date palm sap, the Director of the Institute of Epidemiology, Disease Control and Research (IEDCR) Prof Dr Tahmina Shirin, said, "Recently, we are observing a profound interest among people to consume raw date palm sap and also involve in promoting this culture through social media.
"People indulge in it without knowing the havoc it can create. Even if someone says they have taken precautions while collecting raw date palm sap, we would urge everyone not to drink raw date palm sap because it is still unsafe."
In Bangladesh, the virus was first reported in 2001, and since then, the NiV has become endemic to this densely populated country, with confirmed cases reported almost every year. Until January 2023, a total of 331 cases of NiV infection have been reported, and 236 patients died.
