Monday, December 9, 2013

Outbreak of Foot and Mouth Disease (FMD) in Tamilnadu , India.

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)
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24/09/2013
China (People's Rep. of)
Xinjiang Production and Construction Corps
A
Cattle
18/09/2013
Mongolia
Ikh burkhant
A
Cattle
05/09/2013
China (People's Rep. of)
Laxi
A
Cattle
19/08/2013
China (People's Rep. of)
Naqu
A
Cattle
10/08/2013
China (People's Rep. of)
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
06/07/2013
Mongolia
Khar nuur
Pending
Cattle
05/07/2013
China (People's Rep. of)
Zhuxi
A
Cattle, Swine
04/07/2013
Mongolia
Sar Bastay
Pending
Cattle, Goats, Sheep





09/06/2013
China (People's Rep. of)
Heping village
A
Cattle, Sheep, Swine
08/06/2013
China (People's Rep. of)
Longzhong
O
Cattle
30/05/2013
China (People's Rep. of)
Qudengyangge village
A
Cattle
27/05/2013
Chinese Taipei
Wuri District
O
Swine
24/05/2013
China (People's Rep. of)
Yongjiu village
A
Cattle
20/05/2013
China (People's Rep. of)
Zhonglou district
O
Swine
17/05/2013
Chinese Taipei
Baozhong Township
O
Swine
16/05/2013
Chinese Taipei
Jinhu Township
O
Swine
15/05/2013
China (People's Rep. of)
Xiaoquzi village
A
Cattle









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.

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