Lumpy skin disease (LSD) is caused by the lumpy skin disease virus (LSDV) which affects cattle and water buffalo. It is characterized by fever, skin nodules, swollen lymph nodes, and reduced milk production. Transmission occurs through arthropod vectors like mosquitoes and flies. Diagnosis involves collecting blood, skin samples, or semen from infected animals showing symptoms like nodules and fever. Treatment focuses on isolation, supportive care, and prevention of secondary infections. Controlling vectors and movement of animals from infected areas are important for prevention along with vaccination of healthy animals near outbreak sites.
2. Introduction:
Lumpy skin disease (LSD) is caused by lumpy skin disease
virus a virus from the family Pox viridae, genus Capripox virus.
The disease is characterized by fever, multiple firm,
circumscribed skin nodules of 2-5 cm in size ,enlarged lymph
nodes, oedema of limbs and dewlap and reduction in milk
production.
LSDV is highly host specific and causes diseases only in cattle
(Bos indicus and B. taurus) and water buffalo (Bubalus bubalis).
Holstein Friesian or crossbred cattle exhibiting higher
morbidity and mortality due to LSD when compared with local
zebu cattle as per the study conducted in Ethiopia.
3. LSDV is not zoonotic disease but is an exotic disease and
categories as LIST A disease of OIE.
Morbidity rate varies between 10 and 20% and Mortality
rates of 1 to 5% .
The principal means of transmission is believed to be by
arthropod vector. Though no specific vector has been
identified to date, mosquitoes (e.g. Culex mirificens and Aedes
natrionus), biting flies (e.g. Stomoxys calcitrans and Biomyia
fasciata) and male ticks (Riphicephalus appendiculatus and
Amblyomma hebraeum) could play a role in the transmission
of the virus.
•Infected bulls can excrete the virus in the semen, however
transmission of LSD via infected semen has not been
demonstrated.
4. Clinical Signs
The incubation period is between 4 and 14 days even up to 28 days
LSD signs range from in apparent to severe disease.
Fever that may exceed 41°C.
Cutaneous nodules of 2–5 cm in diameter develop, particularly on the head,
neck, limbs, udder, genitalia and perineum within 48 hours of onset of the
febrile reaction. These nodules are circumscribed, firm, round and raised,
and involve the skin, subcutaneous tissue and sometimes even the underlying
muscles.
The nodules either regress or progress to necrosis, ulcers and finally
scars.
Capripox viruses are very resistant and remain viable for long
periods, on or off the animal host e.g. they may persist for up to 6
months in shaded animal pens, and for at least 3 months in dry
scabs on the fleece, skin and hair from infected animals
5. Large nodules may become necrotic and eventually fibrotic and persist for
several months (“sit- fasts”); the scars may remain indefinitely. Small nodules may
resolve spontaneously without consequences.
Marked reduction in milk yield in lactating cattle.
Rhinitis, conjunctivitis and excessive salivation.
Enlarged superficial lymph nodes.
Vesicles, erosions and ulcers may develop in the mucous membranes of the
mouth and alimentary tract and in the trachea and lungs.
Limbs and other ventral parts of the body, such as the dewlap, brisket, scrotum
and vulva, may be oedematous, causing the animal to be reluctant to move.
Bulls may become permanently or temporarily infertile.
Pregnant cows may abort and be in anoestrus for several months.
14. Diagnosis:
The following specimens should be collected and sent to the laboratory.
•Whole Blood:
Collect sufficient volume of blood (a minimum of 5 ml) from the jugular Or tail vein
(coccygeal vein) in sterile vaccutainers (10 ml) with EDTA (purple stoppers) and store
at refrigerated temperature (40C) Until shipping in ice.
•Skin nodular lesions or scabs: Collect skin biopsy from skin nodules or scabs (2-4
numbers) preferably from upper body surface of each animal in sterile leak-proof
containers with sufficient volumes of viral transport medium or sterile phosphate
buffer saline with antibiotic (Streptopenicillin) and store at refrigerated temperature
(40C) until shipping in ice. If shipping period is >48 hrs., ship in dry ice.
•Semen: In case of affected bulls used for breeding, besides blood, collect 2-3 ml of
raw semen in sterile leak-proof containers and store at -80oC or liquid nitrogen until
shipping in dry ice.
3. Referral lab for confirmation : NIHSAD Bhopal .
15. Clinical Surveillance
Clinical surveillance of susceptible cattle population for nodular skin
lesions should be carried out along with recording of morbidity and mortality
data in LSD-suspected areas.
Monthly clinical surveillance data should be send to DAHD in the format
annexed.
Treatment
Sick animals are to be kept in isolation.
Symptomatic treatment of affected animals may be carried out in
consultation with veterinarian.
Administration of antibiotics for 5-7 days to check secondary infection may
be considered on case to case basis to check secondary bacterial infection.
16. Administration of anti-inflammatory and anti-histamine preparation
may also be considered.
In case of pyrexia, paracetamol can be given.
Application of antiseptic ointment with fly-repellent property over the
eroded skin is recommended.
. Parenteral / oral multivitamins is advised.
Feeding of liquid food, soft feed and fodder and succulent pasture is
recommended for the infected animals.
17. Prevention and Control:
•Awareness campaign about the disease and its clinical signs.
•Immediate isolation of sick/ infected animals from the healthy animals.
•Any animal suspected of febrile nodular skin disease should not be introduced
into the unaffected holding or farm.
•Vector control : Efforts should be made to reduce the vector population in
affected areas. Unaffected animal should be applied with insect (ticks, flies,
mosquitoes, fleas, midges) repellent to minimize mechanical transmission of
LSD.
•Ensure strict control of animal movement from affected areas to free areas and
to local animal markets.
•Trade of live cattle, participation in fairs, shows should be banned immediately
upon confirmation of the disease in the affected areas.
•Cattle markets located within 10 km radius of the epicentre of infection should
be closed
18. • Thorough cleaning and disinfection of affected personnel, premises and
contaminated environment including vehicles plying through the affected
animal holdings should be carried out.
Appropriate chemicals/disinfectants ; [Ether (20%), chloroform,
formalin (1%), phenol (2%/15 minutes), Sodium hypochlorite (2–3%),
iodine compounds (1:33 dilution), quaternary ammonium compounds
(0.5%)].
Disposal of carcass of LSD-affected animals.
In cases of mortality, animal carcass should be disposed of by deep burial.
19. Guidelines for Goat Pox Vaccination in Bovines in suspected LSD cases.
1. As per the GOI advise Goat pox vaccine (Uttarakhasi strain) can be given
to bovine both cattle and buffaloes .
2. Calves of 4 months and above can be vaccinated.
3. Only Unaffected healthy animals should be vaccinated.
4. 100 dose of goat pox vaccine vial needs to be diluted with 100 ml of
chilled normal saline and administer 1 ml of vaccine to each animal by
subcutaneous route.
5. Ensure that each dose should contain 103 TCID50 GPV.
6. Vaccination can be given on neck region preferably.
7. Ring vaccination of animals in and around 5 km radius from the
epicentre of LSD out break should be carried out.
8. Maintenance of cold chain and change of needles should be followed for
effective vaccination.