Bush meat trade poses virus threat
Nearly 75% of emerging infectious
diseases in humans are of zoonotic origin, with majority of them originating
from contact with wildlife. These infectious diseases acquired via the wildlife
trade are increasingly becoming a concern to global public health.
SARS, avian flu, swine flu and
Ebola all began in animals before somehow mutating and spreading to humans. SARS
emerged as a respiratory and gastrointestinal disease in southwest China and
within months had spread to 29 other countries, eventually leading the 8098
cases and 714 deaths. Masked palm civets traded in the markets of Guangdong
were found to be infected and a large proportion of the early cases were
restaurant workers who butchered wildlife from these markets.
In a new study conducted by Smith
K. M. and colleagues published in the PLoS One journal, they reported
potentially dangerous viruses entering the US through illegally imported
wildlife products. For this study bush
meat was defined according to the Oxford Dictionary as the meat of African wild
animals. The researchers examined bush meat passing through the John F Kennedy
(JFK) airport in New York from October 2008 to September 2010. Also at the beginning of
April 2010, products seized from the Philadelphia, Washington Dulles, George
Bush International, Houston and Atlanta Hartsfield-Jackson International were
included in the study.
Figure 1: Non-human primate bush meat specimens confiscated at US airports.
Examples of smuggled simian bush meat (a) skull (b) hand (c) skull and torso, and (d) arm.
The researchers
examined 44 animals – 35 rodents and 9 primates. Simian foamy virus (SFV) and
two herpesviruses - cytomegaloviruses (CMV) and lymphocryptoviruses (LCV) - were
detected in the smuggled non-human primate (NHP) bush meat. SFV and CMV were
detected in two non-human primates originating from Nigeria namely the
Nigerian-Cameroon chimpanzee and the greater white-nosed monkey. These
non-human primates have been classified has “endangered” and “vulnerable”
respectively by the International Union for Conservation.
SFV is a zoonotic infection
of humans. The mode of transmission is poorly understood and infected people reported sustaining a
NHP exposure (mostly bites) others did not, suggesting a less invasive mode of
infection is possible. These viruses are probably not easily spread from
human-to-human, although persistent infection has been documented. Several SFV-positive
people reported donating blood while infected and because blood banks do not
screen for SFV, secondary transmission via contaminated blood donations may be
possible.
The herpesviruses
detected are not considered dangerous to humans however related viruses cause
disease in humans.
These results are the first
demonstration that illegal bush meat importation could act as a conduit for
pathogen spread, and therefore implementation of disease surveillance of the
wildlife trade will help facilitate prevention of disease emergence.

Comments
Post a Comment