Agricultural Intensification andNipah Virus Emergence

Jonathan Epstein DVM, MPH@epsteinjon

EcoHealth Alliance@ecohealthnyc #onehealth2016

Projections of livestock intensification

“Meat consumption in developing countries has risen from 10 kg per person per year in 1964-66 to 26 in 1997-99. It is projected to rise still further, to 37 kg per person per year in 2030.”

“A continued shift in production methods can be expected…towards more intensive and industrial methods.”

-UN Food and Agriculture Organization

World Agriculture: Towards 2015/2030. FAO 2002

Sg. Nipah

Ipoh

Nipah virus index farm

• 30,000+ pigs

• Network of other large farms

• Adjacent to primary forest / fruit bat habitat

Nipah virus in Malaysia, 1998-1999

Human encephalitic cases

11Jan97 16Aug97 16May98 3Oct98 2Jan99

Perak

01

23

4

27Mar99

Selangor

Nu

mb

er

of

case

s0

12

34

26Dec98

Negeri Sembilan

Week of onset of illness

01

02

03

04

0

Num

ber

of

cases

7%

(29)

Distribution of NiV in Malaysian

Pteropus spp.

Pulau Tioman

Tanjung Agas

47%

(34)

Lenggong52%

(27)

K. Berang

38%

(13)

58%

(24)

38%

(26)

Tk. Memali

17%

(12)

Muar

Benut

6%

(1164)

Pig and mango production, Malaysia

Pulliam, Epstein et al., J. R. Soc. Interface 2012

12

Intervention: buffer zone

• No orchards near livestock enclosures

• Removes bat-livestock interface

• Still allows for income from cultivation

www.freemalaysiatoday.com

Nipah virus in Bangladesh and India

• 20+ outbreaks reported since 2001

•>300 cases (~75% cfr; up to 100%)

• Spatial and seasonal patterns

• Bat-to-human transmission1,2

• Human-to-human transmission

1. Hsu et al. EID 2005; 2. Gurley et al, 2008

Spillover via date palm sap

1. Luby et al Emer. Infect. Dis. 20052. Khan et al., EcoHealth 2011Photo (left) J. Epstein EcoHealth Alliance (right) S.U. Khan

Henipaviruses in domestic animals

• Non-neutralizing Abs found in cattle (6.5%), goats(4.3%) and pigs (44.2%)1

• Clinically “normal” animals

• Farmers feed bitten fruit

1. Chowdhury S, Khan SU, Crameri G, Epstein JH, Broder CC, et al. (2014), PLoS Negl. Trop Dis.Photo: J. Epstein, EcoHealth Alliance

Blocking access to date palm sap

• Bamboo skirt: simple, inexpensive, easy, but time consuming

• Effective at excluding pests

• Incentive to adopt? • Financial, not health related1

1. Nahar et al. Global Health Promotion. 2014 Photo J. Epstein EcoHealth Alliance

Evidence for Henipavirus infection in bats*

Confirmed human Henipavirus infection

Henipavirus Distribution

Conclusions

• Agricultural intensification drives disease emergence

• Simple interventions needed to disrupt wildlife-livestock-human interfaces

• Behavior change to adopt interventions