Outbreak
of Foot and Mouth Disease (FMD) in Tamilnadu
, India
The
current outbreak of Foot and Mouth Disease (FMD) among cattle has significantly hit milk production in Tamil Nadu. Foot –
and Mouth disease is a viral disease that affects cloven-hoofed animals, including domestic
and wild bovids. The virus causes a high
fever for two or three days, followed byblisters inside the mouth and on the feet that may rupture and cause lameness. The disease was
initially described in the 16th century and was the first animal pathogen
identified as a virus.
The
FMD outbreak in world ( Last 6 months)
|
|
Country
|
|
|
|
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24/09/2013
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Xinjiang Production and Construction Corps
|
A
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Cattle
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18/09/2013
|
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Ikh burkhant
|
A
|
Cattle
|
|
05/09/2013
|
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Laxi
|
A
|
Cattle
|
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19/08/2013
|
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Naqu
|
A
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Cattle
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|
10/08/2013
|
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Qiaze
|
A
|
Cattle
|
|
05/08/2013
|
China (People's Rep. of)
|
Quma township
|
A
|
Cattle
|
|
05/08/2013
|
China (People's Rep. of)
|
Randui village
|
O
|
Cattle, Sheep / goats
|
|
22/07/2013
|
China (People's Rep. of)
|
Duobuzha
|
O
|
Cattle
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|
06/07/2013
|
Mongolia
|
Khar nuur
|
Pending
|
Cattle
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|
05/07/2013
|
China (People's Rep. of)
|
Zhuxi
|
A
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Cattle, Swine
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|
04/07/2013
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Mongolia
|
Sar Bastay
|
Pending
|
Cattle, Goats, Sheep
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|
|
|
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|
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09/06/2013
|
China (People's Rep. of)
|
Heping village
|
A
|
Cattle, Sheep, Swine
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|
08/06/2013
|
China (People's Rep. of)
|
Longzhong
|
O
|
Cattle
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|
30/05/2013
|
China (People's Rep. of)
|
Qudengyangge village
|
A
|
Cattle
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|
27/05/2013
|
Chinese Taipei
|
Wuri District
|
O
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Swine
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|
24/05/2013
|
China (People's Rep. of)
|
Yongjiu village
|
A
|
Cattle
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|
20/05/2013
|
China (People's Rep. of)
|
Zhonglou district
|
O
|
Swine
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|
17/05/2013
|
Chinese Taipei
|
Baozhong Township
|
O
|
Swine
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16/05/2013
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Chinese Taipei
|
Jinhu Township
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O
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Swine
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15/05/2013
|
China (People's Rep. of)
|
Xiaoquzi village
|
A
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Cattle
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Virus:
FMD is caused by a
non-enveloped Aphtovirus of the family Picornaviridae, existing in seven
distinct serotypes of FMD virus, namely, O, A, C, SAT 1, SAT 2, SAT 3 and Asia
1, most of them with many more subtypes. Infection or vaccination with one
serotype, or in some cases even a different sub-type of the same serotype, does
not confer immunity against another. The genomic nature of FMD virus is RNA.
Transmission : The
virus is spread easily by animated and non-animated vectors, notably the
incubating or clinically affected animal or its products, but may also spread
airborne over substantial distances.
FMD, characterised by
a vesicular condition of the feet, buccal mucosa and, in females, the mammary
glands, cannot be differentiated clinically from other vesicular diseases.
Pic: 1 : FMD Virus
Pathogenesis
Transmission of FMD
is generally by contact between susceptible and infected animals. Infected
animals have a large amount of aerosolized virus in their exhaled air, which
can infect other animals via the respiratory or oral routes. All excretions and
secretions from the infected animal contain virus, and virus may be present in
milk and semen for up to 4 days before clinical signs appear. Aerosolized FMD
virus can spread a considerable distance as a plume, depending on weather
conditions, particularly when the relative humidity is >60% and when the
topography of the surface over which it is dispersing does not cause turbulence.
FMD has been transmitted to calves via infected milk, and milk tankers carrying
infected milk have been implicated in the spread of disease between farms.
Fodder can become contaminated after contact with infected animals and
iatrogenic spread of FMD has been reported.The horses, dogs, and cats are not
affected by FMD, they can act as mechanical vectors, as can humans.
The primary site of
infection and replication is usually the mucosa of the pharynx, although the
virus can enter through skin abrasions or the GI tract. Virus is distributed
through the lymphatic system to sites of replication in the epithelium of the
mouth, muzzle, feet, and teats, and also to areas of damaged skin (eg, the
knees and hocks of pigs kept on concrete). Vesicles develop at these sites and
rupture, usually within 48 hr. The viremia persists for 4−5 days. Antibody
production can be detected from 3–4 days after the first clinical signs and is
usually sufficient to clear the virus.
The incubation period
for FMD is 2–14 days, depending on the infecting dose, susceptibility of the
host, and strain of virus—in pigs, it may be as short as 18 hr with some
strains of FMD virus. The clinical signs are more severe in cattle and
intensively reared pigs than in sheep and goats.
In cattle and pigs,
after the incubation period, anorexia and fever of up to 106°F (41°C) may
develop. Cattle salivate and stamp their feet as vesicles develop on the
tongue, dental pad, gums, lips, and on the coronary band and interdigital cleft
of the feet. Vesicles may also appear on the teats and udder, particularly of
lactating cows and sows, and on areas of skin subject to pressure and trauma,
such as the legs of pigs. Young calves, lambs, kids, and piglets may die before
showing any vesicles because of virus-induced damage to the developing cells of
the myocardium. Milk yield drops dramatically in milking animals, and all
animals show a loss in condition and growth rate that may persist after
recovery. Sheep and goats may develop only a few vesicles on the coronary band
and in the mouth. Vesicles in the mouth, even when severe, usually heal within
7 days, although recovery of the tongue papillae takes longer. Lesions on the
mammary gland and feet frequently develop secondary infections, resulting in
mastitis, underrunning of the sole, and chronic lameness. In pigs, the complete
horn of the toe may be lost. Cattle and deer may also lose one or both horns of
the foot, and deer may shed their antlers.
Prevention and
control
The initial measures
in the global strategy for dealing with FMD are early detection and warning
systems and prevention and rapid response measures and mechanisms in place.
This contributes to monitoring the occurrence, prevalence and characterisation
of FMD viruses.
Protection of FMD
free countries, areas or zones is enhanced with stringent import and
cross-border animal movement controls and surveillance.
It is essential for
livestock owners and producers to maintain sound biosecurity practices to
prevent introduction/spread of the virus. Measures that are recommended at the
farm level include:
·
control
the introduction of new animals to existing stock;
·
control
over access to livestock by people and equipment;
·
maintain
sanitation of livestock pens, buildings, vehicles and equipment ;
·
monitor
and report illness;
·
appropriate
disposal of manure and dead carcasses.
Contingency planning
for potential outbreaks will identify the elements included in a response
effort to eradicate the disease, such as:
humane destruction of
all infected, recovered and FMD-susceptible contact animals;
appropriate disposal
of carcasses and all animal products;
surveillance and
tracing of potentially infected or exposed livestock;
strict quarantine and
controls on movement of livestock, equipment, vehicles, and;
thorough disinfection
of premises and all infected material (implements, cars, clothes, etc.)
In endemic areas, culling may be complemented
by vaccination for susceptible livestock. Vaccines used must protect against
the particular virus strain prevalent in the area.
Herbal Medicine to Treat FMD
According to TANUVAS , There are two types of herbal
medications to treat animals affected with FMD. The first involves the making
of a herbal and spicy mixture using ingredients like cumin, garlic, pepper,
turmeric, coconut shavings, fenugreek and applying it on the ulcerated and
blistered gums of the infected animal, thrice a day, in small quantities to
ensure it is chewed properly.
Another herbal medicine involves a concoction of
herbal leaves fried in gingelly oil. This mixture is applied to the blistered
limbs of infected cattle to keep it free from maggots and speed up the healing
process.
References:
