agricultural intensification and nipah virus emergence
TRANSCRIPT
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