The document discusses Nipah virus infection. It covers the organism, history, epidemiology, transmission, disease in humans and animals, and prevention/control. Nipah virus is transmitted from its reservoir in fruit bats to pigs and humans. It causes severe respiratory disease and encephalitis in these hosts. Outbreaks have occurred in Malaysia, Singapore, India and Bangladesh through contact with infected pigs or bats/contaminated fruit. The disease poses a serious public health risk with fatality rates up to 75% in humans.

1. NIPAH VIRUS
INFECTION
N
Abdulrahman Mohammed
L-2102-V-21-D
School of Public Health and Zoonoses
GADVASU

2. OVERVIEW
 Organism
 History
 Epidemiology
 Transmission
 Disease in Humans
 Disease in Animals
 Prevention and Control
 Actions to Take

3. SYNONYMS
 Barking Pig Syndrome
 Porcine Respiratory and Encephalitis
Syndrome
 Porcine Respiratory and Neurologic
Syndrome

4. AGENT
 Genus Henipavirus
◦ Virus discovered, 1999
◦ Related to Hendra virus
 Severe, rapidly progressive
encephalitis in humans
◦ High mortality rate
◦ Close contact with infected pigs
 Severe, respiratory disease in pigs

5. NIPAH VIRUS STRUCTURE
Single-stranded negative sense RNA, 18,246 nucleotides in length

6. HISTORY
 1998-1999: Peninsular Malaysia
◦ Human febrile encephalitis, high mortality
◦ New virus discovered
 1999: Singapore
◦ Outbreak in abattoir workers
◦ Pigs imported from Malaysia
● Since 2001 – Bangladesh, India

7. Introduction
 Nipah is the name of the 1st village the virus struck near
Kuala Lumpur in Malaysia.
 Nipah virus is similar to Hendra virus that was discovered in
Australia in 1994.
 Nipah virus was discovered in 1999. It is a paramyxovirus in
the genus Henipavirus; Hendra virus is also within this
genus.
 Different variants of Nipah virus were involved in outbreaks in
Malaysia, Bangladesh, and India, and at least two major
strains of Nipah virus were isolated from pigs in Malaysia.
 Nipah virus causes severe, rapidly progressive encephalitis in
humans, and severe respiratory illness in pigs. Some pigs
may also demonstrate nervous system signs.
 Nipah virus infection has a high mortality rate in humans.
Transmission of the disease to humans is associated with
close contact with infected pigs. Nipah virus survives in the
environment for long periods in favorable conditions; it
survives for days in fruit bat urine and contaminated fruit juice

8. Center for Food Security and Public
Health, Iowa State University, 2011

9. THE MODE OF TRANSMISSION:
from animal to animal &
from animal to human (uncertain)
require close contact with contaminated tissue or body
fluids from infected animals.
Nipah antibodies have been detected in pigs, other
domestic & wild animals.
The role of species other than pigs in transmitting
infection to other animals - not yet determined.
It is unlikely that Nipah virus is easily transmitted to
man
Nipah is transmitted from animals to humans more
readily than Hendra.
Despite frequent contact between fruit bats & humans
there is no serological evidence of human infection
among bat careers.
Pigs were the apparent source of infection among most
human cases in Malaysian outbreak of Nipah, but other
sources, such as infected dogs and cats, cannot be
excluded.
Human-to-human transmission of Nipah virus - not
reported.

10. TRANSMISSION
Reservoir
 Flying foxes (fruit bats)
◦ Carry the virus
◦ Are not affected
 Virus found in
◦ Urine
◦ Partially eaten fruit (saliva?)
 No known secondary host

11.  The primary reservoir for Nipah virus are flying
foxes (also known as fruit bats) of the genus
Pteropus.
 Transmission of Nipah virus from bats to swine
has not been shown conclusively; however, there
are various biologically plausible means for
infected secretions of primary hosts to enter pigs,
including direct contact with infected secretions,
contaminated fruit or dead bats.
 Scavenging animals may also play a role in the
transport of virus into proximity of pigs. Flying
foxes are able to carry the virus without being
affected by it.
 Investigation of potential secondary hosts
(peridomestic species) have also been conducted.
Rats, house shrews, dogs, and chickens have
been tested, but no indication of a secondary host
has been found.

12. TRANSMISSION
 Pigs in Malaysia
◦ Direct contact
◦ Contact with body fluids
◦ Aerosolization of respiratory or
urinary secretions
◦ Vertical transmission across the placenta?
◦ Semen and iatrogenic spread?

13.  It is unclear how the virus was transmitted from bats to
pigs in Malaysia. However, it is suspected that fruit
trees close to pig confinement areas are foraged by
the bats and the virus is spread by urine or saliva-contaminated
partially-eaten fruit on which the pigs
feed.
 The majority of human cases (93%) have been related
to close contact with pigs, either from direct contact or
contact with body fluids, urine, or feces.
 Aerosolization of urinary or respiratory secretions may
be a possible route of transmission and is being
investigated.
 The role of dogs and cats (in close contact with
infected pigs) in the transmission of the disease is also
being explored.
 Anecdotal evidence suggests that vertical
transmission may occur across the placenta.
 Transmission in semen and iatrogenic spread on re-used
needles have also been suggested.

14. TRANSMISSION
 Person-to-person
◦ Not reported in Malaysia
◦ Likely in Bangladesh and India
 Nosocomial infections
 Bat-to-person
◦ Not reported in Malaysia
◦ Common in Bangladesh and India
 Contaminated fruit, unpasteurized date palm
juice

15. How did people get infected in
Malaysia?
 The outbreak was concentrated
among pig farmers
-92% of cases reported contact with
pigs
Compared to controls, persons with
Nipah encephalitis were:
-5.6 times more likely to have close
contact with pigs
-3.7 times more likely to have contact
with sick pigs

16. Nipah wildlife studies
 Numerous wild animals trapped and tested
 8 different species of fruit bats sampled
- 4 of the 8 species had antibody
against Nipah virus
 Nipah virus isolated
-urine from Pteropus hypomelanus in
Malaysia
-Urine from Pteropus lylei
-in Cambodia
-in Thailand

17. These are several of the hog confinement barns that were affected
during the Malaysia Nipah virus outbreak. The reservoir fruit bats live in
these caves and feed on the fruit trees that are in close proximity to the
hog confinement barns.
Photo courtesy of James Roth, DVM, PhD, ISU

18. This picture shows additional hog confinement barns in Malaysia. There are
many fruit trees and caves close to this location
Photo courtesy of James Roth, DVM, PhD, ISU

19. How does Nipah virus transmit from
wildlife to humans in Bangladesh?

20. Date palm sap collection
 Late November through March/April
-A tap is cut in the tree in the evening a
clay pot is placed under the tap
-Each morning the pot is removed
-Some sap is sold fresh early in the
morning
 Fruit bats are a nuisance
-drink juice
-defaecate into juice
occasionally drown in juice

21. Date palm sap distribution
 One of the fatal cases was the son of
a date palm sap collector
-drank date palm sap daily
 Heard bats in his date palm trees at night
-found bat excrement on his pot
 Several days prior to the outbreak he sent
date palm sap to his relatives in a nearby
homestead
- 3 cases occurred in the family

22. EPIDEMIOLOGY
 1998-1999: Malaysia
◦ 265 persons hospitalized; 105 deaths
◦ Primarily adult males with swine contact
◦ Disease in swine
 Severe respiratory disease
 Transmitted by movement of infected pigs
 1.1 million pigs culled
 Great economic loss
◦ Surveillance and testing

24. Epidemiology
 Shortly after the 1999 outbreak in Singapore, a
serological survey of various risk groups was
conducted in Singapore. From the 1,469 persons
tested, 22 were found to be infected with Nipah
virus. Ten of these individuals were asymptomatic.
Of the 12 persons (54.6%) demonstrating
symptoms, 9 had encephalitis, 2 pneumonia, and
1 had both.
 1999: Singapore
◦ 22 seropositive persons (1.5%)
◦ All were male abattoir workers
◦ 12 symptomatic
 Encephalitis, pneumonia, or both
◦ 10 asymptomatic

25. Epidemiology
 India reported two outbreaks of Nipah virus encephalitis in the eastern state
of West Bengal, bordering Bangladesh, in 2001 and 2007. Seventy one
cases with 50 deaths (70% of the cases) were reported in two outbreaks.
 An outbreak in Siliguri, West Bengal, India in 2001 was linked to nosocomial
transmission in hospitals and ended after effective barrier nursing
precautions were put in place.
 A second outbreak was reported in 2007 in Nadia district of West Bengal.
Thirty cases of fever with acute respiratory distress and/or neurological
symptoms were reported and five cases were fatal. All five fatal cases were
found to be positive for NiV by RT-PCR.
 A 2004 outbreak of Nipah virus occurred in the Faridpur District of
Bangladesh in mid-March 2004. Thirty-four human cases were identified,
and 26 people (76%) died of the disease. Transmission of the disease may
have occurred through close contact with infected patients or exposure to a
common source).
 2001: Siliguri, 2007: Nadia, India
◦ Nosocomial transmission
 2004: Bangladesh
◦ 34 cases; 26 deaths
◦ Transmission
 Close contact
 Exposure to common source

26. Epidemiology
 2005: Bangladesh
◦ 44 cases; 12 deaths
◦ Contaminated palm fruit juice
 2007: Bangladesh
◦ 7 cases; 3 deaths
◦ Person-to-person transmission
◦ 2013 Since the deadly
pathogen appeared in
Bangladesh 12 years ago, 188
cases and 146 deaths have
been reported; including 12
infections and 10 deaths so far
in 2013.

27.  In 2005, an outbreak began in the Tangail District on
Bangladesh when 13 people lost consciousness after drinking
palm fruit juice. The fruit may have either been contaminated
with fruit bat droppings or saliva as the fruit may have been
partially eaten by the bats. Blood samples from the suspected
cases were sent to the CDC to confirm Nipah virus infection,
and one was a confirmed positive. There were a total of 44
cases and 12 deaths from Nipah virus as of February, 2005).
 In February 2007 an outbreak of Nipah virus encephalitis
occurred in Thakurgaon District of northwest Bangladesh.
Seven people were infected, three of whom died. Although
the source of infection for the index case was not identified,
50% of Pteropus bats sampled from near the outbreak area 1
month after the outbreak had antibodies to Nipah virus
confirming the presence of the virus in the area. The outbreak
was spread by person-to-person transmission.

28. Morbidity and mortality due to Nipah
or Nipah-like virus encephalitis,
South-East Asia Region, 2001-2012
Year/Month Location No. cases No. deaths
Case Fatality
Rate
Jan-Feb 2001 Siliguri (India) 66 45 68%
Apr-May
Meherpur
13 9 69%
2001
(Bangladesh)
Jan-03
Naogaon
(Bangladesh)
12 8 67%
Jan 2004
Rajbari(
Bangladesh)
31 23 74%
Apr-04
Faridpur
(Bangladesh)
36 27 75%
Jan-Mar 2005
Tangail
(Bangladesh)
12 11 92%

29. Jan-Feb 2007
Thakurgaon
(Bangladesh)
7 3 43%
Mar-07
Kushtia,Pabna,
Natore
(Bangladesh)
8 5 63%
Apr-07
Naogaon
(Bangladesh)
3 1 33%
Apr-07 Nadia (India) 5 5 100%
Feb-08
Manikgonj
(Bangladesh)
4 4 100%
Apr-08
Rajbari and
Faridpur
(Bangladesh)
7 5 71%
Jan-09
Gaibandha,
Rangpur and
Nilphamari
(Bangladesh)
3 0 0%
Rajbari
(Bangladesh)
1 1 100%
Feb-Mar 2010
Faridpur,
Rajbari,Gopalg
16 14 87.50%

30. Feb-Mar 2010
Faridpur,
Rajbari,Gopalg
anj,Madaripur
(Bangladesh)
16 14 87.50%
Jan-Feb 2011
Lalmohirhat,
Dinajpur,
Comilla,
Nilphamari and
Rangpur
(Bangladesh)
44 40 91%
Feb-12
Joypurhat,
Rajshahi,
Natore, Rajbari
and Gopalganj
(Bangladesh)
12 10 83%
Total 280 211 75%

31. Disease in Humans
Incubation period: Between 4 & 18 days
In many cases infection is mild or unapparent (sub-clinical).
In symptomatic cases:
onset is usually with "influenza-like" symptoms, with
high fever & muscle pains
Disease may progress to: Inflammation of brain (encephalitis) with
drowsiness, disorientation, convulsions &
coma.
50% of clinically apparent cases die

32. NIPAH PATHOLGY
 Causes a diffuse vasculitis
 The brain is the most severely
affected organ
-tropism to the brain stem
 Virus commonly identified in
-lung
-Kidney

33. Nipah case definition
 Person with fever plus
- New onset seizures OR
- Altered mental status OR
-Severe shortness of breath
 Antibody against Nipah virus
OR
-Part of a cluster of similar cases in the
same
region, at least one of whom was Nipah
antibody positive

34. Disease in Human
 Complications (Malaysian outbreak)
◦ Septicemia (24%)
◦ GI bleeding (5%)
◦ Renal impairment (4%)
 Asymptomatic
◦ Relapse or late-onset encephalitis
◦ Residual neurological deficits
 Treatment: Supportive, ribavirin

35.  Septicemia, bleeding from the gastrointestinal tract, renal
impairment, and other complications can occur in severely ill
patients.
 In the Malaysia outbreak, the mean time from onset of illness to
death was 10.3 days. Duration of illness for those that recovered
was 14.1 days.
 Cases that progress to encephalitis are often fatal. Surviving
patients may have mild to severe residual neurological deficits, or
remain in a vegetative state.
 Patients who recover from neurologic disease may relapse with
encephalitis several months to several years later. Encephalitis can
also occur as long as four years or more after an asymptomatic or
non-encephalitic infection.
 In the Malaysian outbreak, the subclinical infection rate was
estimated to be 8 to 15%. The case fatality rate in the various
outbreaks has varied from 33% to approximately 75%; the overall
case fatality rate for all outbreaks in Bangladesh between 2001 and
February 2005 was 64%. Current treatment involves intensive
supportive care. Early treatment with ribavirin may reduce the
severity of the disease.

36. Disease in Animals
◦ Highly contagious
◦ May be asymptomatic
◦ Acute fever (>104°F)
◦ Severe respiratory disease
 Characteristic cough – harsh, “barking”
◦ Neurological changes
◦ Low mortality

37. Disease in Animals
 Dog
◦ Distemper-like signs
◦ Fever, respiratory distress
◦ Ocular and nasal discharge
 Cat
◦ Fever, depression
◦ Severe respiratory signs
 Horses
◦ Encephalitis

38. Diagnosis
 Differentials for swine
◦ Classical swine fever, PRRS,
pseudorabies, swine enzootic pneumonia,
porcine pleuropneumonia
 Diagnostic tests
◦ ELISA
◦ Immunohistochemistry
◦ PCR
◦ Virus isolation

39. Treatment
 No effective drug therapies available
yet.
 Ribavirin-reduces mortality
 Recent development for NiV antivirals
focus on inhibitors of fusion and receptor
binding
 Soluble versions of the G glycoprotein
and Ephrin B2 shown to inhibit NiV
envelope-mediated infection
 No passive immunoprophylaxis, antiviral
chemoprophylaxis, or vaccine is
currently available

40. Recommended Actions
 Nipah virus is a very dangerous pathogen. It has been classified as
a Biosafety level 4 agent. If you suspect a potential Nipah virus
outbreak, contact your state veterinarian, or your state public health
veterinarian IMMEDIATELY!
 Avoid all contact with potentially infected species (pigs, dogs, cats),
until the proper authorities are consulted.
 Because Nipah virus can be transmitted from person-to-person,
barrier nursing should be used when caring for infected patients.
Patients should be isolated, and personal protective equipment,
such as protective clothing, gloves, and masks should be used.
 IMMEDIATELY notify authorities
 Federal
◦ Area Veterinarian in Charge (AVIC)
 State
◦ State veterinarian
 Quarantine

41. Prevention and Control
 Keep fruit bats away from
pigs
 Do not drink unpasteurized
fruit juices
 Wash, peel, and/or cook all
fruit thoroughly before
eating

42. Malaysia outbreak control
 Outbreak ceased following the culling
of over 2 million pigs
-Fruit trees no longer permitted above
pig pens
-Pork industry decimated
No cases of Nipah recognized in
Malaysia from people or animals since

43. Nipah virus (NiV) causes seasonal outbreaks
in humans in Bangladesh that coincide with the
date palm sap harvesting season, November to
March
After intervention (Khan et al.,
2012) from 83% to 2%
A picture taken by infrared night observation
showing a small fruit bat (in circle) licking sap
from the shaved surface of a date palm tree
without any intervention

44. Nipah as a
Biological Weapon
 CDC Category C Bioterrorism Agent
 Emerging pathogen
 Potentially high morbidity
and mortality
 Major health impact
 Aerosolization potential
 Economic impact
 Social disruption (fear, panic)

45. References
 Oxford Textbook of Zoonoses
 World Health Organization
-www.who.int
 World Organization for Animal Health (OIE)
◦ www.oie.int
 U.S. Department of Agriculture (USDA)
◦ www.aphis.usda.gov
 Centers for Disease Control and Prevention
-www.cdc.gov
 Center for Food Security and Public Health
◦ www.cfsph.iastate.edu
 USAHA Foreign Animal Diseases
(“The Gray Book”)
◦ www.usaha.org/pubs/fad.pdf

46. THANK YOU
FOR
LISTENING