Intelligently Evil Little Virus: Nipah Virus

Nipah virus has been all over the news and sitting here I am like what is this? With news headlines like ‘Napah virus ‘under control’ in India- but Britain and the world must be alert for signs of infected travellers’ from The Telegraph, ‘An outbreak of Nipah Virus in India can explain the future of infectious disease’ from UN Dispatch and ‘Nipah Virus, Rare and Dangerous, Spreads in India’ from the New York Times, SHOCK HORROR this disease sounds like the new Ebola. How delightfully horrifying.

But the real question before I decide if this virus is cool or not, what is Nipah virus?

It is transmitted from the natural host fruit bats to humans. Can I hear Ebola there?

There is the potential of it spreading. Hello Ebola!

Okay. Okay. Nipah virus is zoonotic. It was first identified in Kampang Sungai Nipah in Malaysia where the name derived from. The symptoms of the disease include fever, headache, drowsiness, mental confusion; caused by the severe inflammation that is occurring in the brain. It is fatal for up to 75% of people as coma occurs within 24 - 48 hours. Let’s say you recover, there is a 20% chance you will have personality changes, seizures or even relapse. Considering that according to the WHO Ebola virus disease has a fatality of 50%, Nipah virus is serious shit!

So far, the virus has remained fairly happy, confined in Asia. Starting in Kampang Sungai Nipah, Malaysia in 1998, then Singapore in 1999, then Bangladesh and India in 2001, 2004 and 2007 and Kerala, India recently. In Malaysia, pigs were the intermediate hosts putting the zoonotic aspect of transmission in the lime light. In the Bangladesh outbreak in 2004, fruit bats contaminated date palm sap and in India human to human transmission occurred making the spread of Nipah virus even more complicated.

  

The spread of Nipah virus is what the world is terrified of. As a zoonotic disease that is transmitted from bats, pigs, domestic animals and through direct human contact to bodily fluids, it would be difficult to control in crowded cities such as London in those filthy disease ridden underground tubes (trust me, read the included articles for more info). This included with the amazing transport links connecting people to and from all over the world, the 4 – 14 days of incubating (AKA hiding) that the virus takes and the lack of vaccine or effective treatment makes the lack of knowledge of Nipah virus in the first place amazing weaponry for surprise. 

There is lots out there about the symptoms, diagnosis, prevention, and outbreaks but how does this little virus cause disease? The pathology described in an infected human brain; ‘systemic vasculitis’, ‘perivascular cuffing’, ‘thrombosis’, ‘necrosis’ and ‘endothelial cell syncytia’. Gosh big words right. Don’t worry they just fly over my head as well.

Break it down chick! Vasculitis is the general term referring to the inflammation of arteries and veins that progresses to necrosis, leading to the narrowing of the vessels and systemic as this affects the blood vessels in the brain, lungs, heart and kidney. Lymphocytes or plasma cells are also seen to accumulate around the vessels affected referred to as perivascular cuffing. Thrombosis is simply blood clots in the vessel. Necrosis we should all know but if not it’s the death of cells, which can be caused by lack of blood supply.  Syncytia are multi nucleated large cells caused by the fusion of neighbouring infected cells so ‘endothelial cell syncytia’ refers to this occurring in endothelial cells which line the interior surface of blood vessels. This just creates a big mess in the brain!

This mess carries on in the spleen, kidneys and lungs. In tiny air sacs in the lungs, fibrinoid necrosis occurs (fibrin accumulation in the tissue) close to vessels as well as haemorrhage and oedema. In both the spleen and kidneys necrosis is seen.

Pathology of acute Nipah infection as seen in a Syrian Hamster: A: LIVER Large artery in liver showing focal, fibrinoid necrosis with surrounding inflammation. B: HEART Myocardial necrosis (thin arrow) with adjacent inflammation (thick arrow). C: HEART Multiple endothelial multinucleated syncytium (arrows) in pulmonary artery. D: LUNG Viral RNA was demonstrated in endothelial syncytia (thin arrows) and vascular smooth muscle (thick arrow) in the same lung. E: BRAIN Necrosis and karyorrhexis in a cerebral vessel. F: BRAIN Viral antigen localized to endothelium (thick arrow) and smooth muscle (thin arrows) in a meningeal blood vessel. (Image from A Golden Hamster Model for Human Acute Nipah Virus Infection Wong et al, 2003)

Finding out about this disease has freaked me the hell out! But I do have to say what an intelligently evil little virus. 

Further reading

Nine antibiotic-resistant superbugs found on London’s travel network, says study-https://www.independent.co.uk/life-style/health-and-families/nine-antibiotic-resistant-superbugs-london-tube-travel-network-buses-taxi-cab-a7736666.html

Tube travellers inhale 12m toxic particles a minute- https://www.thetimes.co.uk/article/tube-travellers-inhale-12m-toxic-particles-a-minute-hh2ss6f7m

Animal models of disease shed light on Nipah virus pathogenesis and transmission- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4268059/

Experimental Infection of Syrian Hamsters with Aerosolized Nipah virus- https://academic.oup.com/jid/advance-article-abstract/doi/10.1093/infdis/jiy357/5038367?redirectedFrom=fulltext

A Golden Hamster Model for Human Acute Nipah Virus Infection- https://ajp.amjpathol.org/article/S0002-9440(10)63569-9/fulltext?code=ajpa-site