Avian Flu Diary: The IDs Of March: Another Suspected Nipah Cluster In Bangladesh ?

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Just over a year ago the WHO released their 2018 revised list of Blueprint Priority Diseases, which selected Infectious Diseases (IDs) with a `. . . potential to cause a public health emergency' and for which there is an ` . . . absence of efficacious drugs and/or vaccines'.

Crimean-Congo haemorrhagic fever (CCHF)

Ebola virus disease and Marburg virus disease

Lassa fever

Middle East respiratory syndrome coronavirus (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS)

Nipah and henipaviral diseases

Rift Valley fever (RVF)

Zika

Disease X

Although it was only first identified a couple of decades ago, one of the most fascinating pathogens in the rogue's gallery above is the Nipah virus.

The virus first came to light in 1998, when Nipah - normally carried by fruit bats common to S.E. Asia - sparked an outbreak in Malaysia, which spread first from bat to pigs - and then from pigs to humans - eventually infecting at least 265 people, killing 105 (see Lessons from the Nipah virus outbreak in Malaysia).

Since then, we've seen a couple of dozen outbreaks in India, Pakistan, and most commonly, Bangladesh.

In May of 2018 the Indian Government announced their third NiV outbreak since 2001, which began in Kerala and eventually led to the infection of 20 people (see Nipah Transmission In Kerala Outbreak), many of whom were exposed in a healthcare setting.

In the 2013 paper The pandemic potential of Nipah virus by Stephen P. Luby, the author writes (bolding mine):

Characteristics of Nipah virus that increase its risk of becoming a global pandemic include: humans are already susceptible; many strains are capable of limited person-to-person transmission; as an RNA virus, it has an exceptionally high rate of mutation: and that if a human-adapted strain were to infect communities in South Asia, high population densities and global interconnectedness would rapidly spread the infection.

And last July, in IJID: Enhancing Preparation For Large Nipah Outbreaks Beyond Bangladesh, we looked at a new open-access article that appeared in the International Journal of Infectious Diseases, that discussed the potential of the Nipah virus producing a large urban epidemic, similar to what we saw in West Africa with Ebola in 2014.

Ten days ago, Bangladeshi media reported on the deaths of 5 family members in the district of Thakurgaon, in the far north-west of Bangladesh. CIDRAP carried published a synopsis on March 4th.

Bangladesh confirms Nipah case in suspected family cluster

Lab tests in the investigation into the early February deaths of five family members in Bangladesh revealed that one was infected with Nipah virus, according to a report from the Daily Star, Bangladesh's largest English-language newspaper, which cited a statement from the country's Institute of Epidemiology, Disease Control and Research (IEDCR).

The family members are from Baliadangi upazila in Rangpur division in the far northwest of the country. IEDCR committees have conducted investigations at hospitals and other locations, collecting samples from health workers, as well as other family members, neighbors, and villagers. None of other family member tested positive.

The IEDCR said it's not known if the patient whose sample was positive had a history of drinking raw date palm sap, a known risk factor for the disease because of virus contamination through bat droppings. The agency said the four others may have been infected by the individual whose samples were positive.

Nipah virus is harbored by bats, which can transmit the disease to people and other animals. It is one of three priority areas targeted by the Coalition for Epidemic Preparedness and Innovations (CEPI). In 2018, a Nipah virus outbreak in India's Kerala state was linked to 17 deaths. In 2018, Bangladesh recorded three Nipah virus cases, one of them fatal, according to a list from the IEDCR.

Mar 4 Daily Star story
IEDCR yearly distribution of Nipah virus cases

Today, Bangladeshi media are reporting another similar case, from the same region, with three family members hospitalized with suspected Nipah infection.

3 of a family suspected to be infected with Nipah virus

Publish Date - March 15, 2019, 12:02 PM
UNB NEWS - UNB NEWS

Thakurgaon, Mar 15 (UNB)– Three members of a family from Baliadangi Upazila’s Ujarmoni village are suspected to have been infected with the deadly Nipah Virus.

The victims have been named as Dulali Begum, 28, wife of Nasirul Islam, her son Siam, 8 and daughter Nitu, 4. They were taken to Rangpur Medical College Hospital on Thursday, said ABM Maniruzzaman, the resident medical officer of Baliadangi Upazila Health Complex.

He said the victims had been suffering from fever for the last three days. They also reported headache and vomiting. The trio was first taken to Thakurgaon Modern Sadar Hospital and later shifted to RMCH.

Nipah virus is transmitted from animals to humans and can also be transmitted through contaminated food or directly between people, according to World Health Organisation. There is no vaccine for the virus, which is spread through body fluids and can cause inflammation of the brain.

Dulali’s husband Nasirul Islam said his wife and children fell sick after eating jujube on Wednesday night.

Thakurgaon Civil surgeon Dr Abu Mohammad Khairul Kabir said their blood samples had been collected for testing. A medical team from the Institute of Epidemiology, Disease Control and Research is scheduled to visit RMCH.

While their illness could be due to something other than Nipah, there are reasons - beyond their symptomology and close proximity to the last outbreak - to suspect the virus. All three reportedly ate Jujube (aka red dates, Chinese dates) prior to falling ill.

As the virus is carried by fruit bats of the Pteropodidae family - which have a preference for roosting in the tops of trees rather than caves - this allows them to contaminate fruit (and date juice collection jars) with their virus laden urine and feces.

Past epidemiological investigations have fingered the consumption of raw (uncooked) date palm juice in Bangladesh as Nipah’s primary route into the human population. While Jujube comes from a different type of tree, the same principal could apply.

Date Palm Sap Collection – Credit FAO

Collection of date palm juice is a seasonal activity (December - May) in Bangladesh, which not surprisingly, is the same time period that defines their Nipah season.

For more on the Nipah virus, and other bat-borne pathogens of concern, you may wish to revisit last January's review of: