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By Dr. Ibne Ali, IMN PyrophosUpdated October 20265 min read

Ranikhet Disease / Newcastle Disease – ND in Poultry

Introduction: What is Ranikhet Disease?

  • Ranikhet disease (RD), also known as Newcastle disease (ND) or pseudo-plague, is a sudden and severe, rapidly spreading viral disease affecting wild and domestic birds.
  • It is characterized by rapid onset, respiratory symptoms, nervous manifestations, and varying mortality.
  • Ranikhet disease primarily affects chickens and turkeys, but most poultry and many wild and domestic birds are susceptible.
  • For nd treatment in poultry we will see in another blog
  • It has a worldwide distribution.
  • In India, Ranikhet is the most dreaded viral disease of poultry and is considered the number one cause of deaths every year.
  • The first outbreaks were recorded in 1926 in Java, Indonesia, and Newcastle, England (hence the name 'Newcastle disease'). In India, the disease was first reported from Ranikhet, Uttaranchal, in 1927, hence the name 'Ranikhet disease'.
  • The economic impact of ND is huge, including direct losses (mortality) and indirect costs like vaccination and testing in disease-free countries. In developing countries like India where eggs and poultry meat are main protein sources, endemic NDV significantly impedes poultry industry development.
  • From a public health perspective, ND is considered a minor zoonosis. Transmission to humans is anecdotal and usually results in ocular infection (conjunctivitis, eyelid edema, watery eyes). Headache and fever are sometimes observed. Newcastle disease is a minor zoonosis generally resulting in conjunctivitis.

The Virus: Cause, Classification, Structure, Genetic Variation

  • Ranikhet disease is caused by a group of closely related viruses that form the avian paramyxovirus type 1 serotype (APMV-1 or PMV-1).
  • Newcastle disease virus (NDV) is part of the genus Avulavirus, belonging to the family Paramyxoviridae.
  • These viruses are enveloped, single-stranded RNA viruses with negative polarity.
  • They have a nucleocapsid with helical symmetry, surrounded by an envelope derived from the host cell membrane.
  • The envelope has spicules of two glycoproteins:
  • Hemagglutinin-neuraminidase (HN): responsible for virus attachment to cellular receptors.
  • F glycoprotein: induces fusion of the viral envelope with the cell membrane, allowing viral RNA entry.
  • All avian paramyxoviruses agglutinate red blood cells of birds.
  • Nine different serotypes of avian paramyxovirus (PMV-1 to PMV-9) are distinguished using hemagglutination inhibition (HI) tests. NDV strains belong to PMV-1.
  • Antigenic variations exist within the PMV-1 group, identifiable using monoclonal antibodies. Cross-reactions can occur between PMV-1 and PMV-3 viruses, particularly those isolated from turkeys and psittacines.
  • Considerable genetic diversity is linked to spatio-temporal origin and host species.
  • Sequencing the fusion (F) protein gene has identified at least six distinct lineages of NDV (1-6).
  • Complete genome analysis shows two major divisions (Class I and II), with Class II further subdivided into eight genotypes (I-VIII).
  • These genetic variations can affect antigenicity and potentially vaccination effectiveness.

How it Spreads (Epidemiology – Practical Points)

Virocon IMN Pyrophos

Viral outbreak support

Virocon

Phytobiotic support with herbal antioxidants, capsicum, garlic and allium extracts, vitamins E and C and probiotics. Supportive care in viral outbreaks such as ND, IB, IBD, IBH, LPAI, CIA and Marek’s; helps reduce mortality.

Dose: 1 g per 5 kg body weight or 3 g per litre. Give in the morning in fresh water and let birds finish it in 3–4 hours.

500 g ₹579MRP ₹950

  • Ranikhet disease virus is highly contagious and spreads easily.
  • Transmission Routes:
  • Fecal-Oral Route: Through ingestion of contaminated feed and drinking water. Viruses primarily growing in the intestine are spread this way.
  • Airborne Route: Through inhalation of aerosol and droplets shed from the respiratory tract. Birds with respiratory disease shed virus in mucus particles. Coughing helps make the virus airborne. The European epidemic of 1970-1972 had a very pronounced respiratory tropism and spread rapidly via airborne transmission.
  • Virus Shedding: Infected birds shed the virus through aerosol and/or droppings after replicating in their respiratory and/or digestive tracts.
  • Survival: Although enveloped, NDV is relatively stable outside the host. It can survive for several days or even months in the presence of organic material, depending on temperature and surrounding moisture. In infected carcasses, the virus can survive for several weeks at cool temperatures or several years if frozen. Faeces, where virus concentrations can be high, are an excellent medium for survival; they remain infective for over a month even at 37°C.
  • Key Sources and Vectors (Practical Points):
  • Humans and Equipment: The greatest possibility for spread is often by humans and their equipment. Spread occurs via contaminated material (fomites) like soil, litter, equipment, clothes, and shoes. Movement of people and vehicles must be limited and include disinfection and change of clothing/footwear. Vaccinators moving farm to farm have been involved in virus spread. Humans themselves can carry the virus, potentially in the conjunctival sac of the eye. Mechanical transfer of infectious material (usually faeces) is a common human-mediated spread method.
  • Live Birds: Movement of live birds is a major factor. This includes commercial poultry, wild birds, pet/exotic birds (like psittacines), game birds, and racing pigeons. Exotic birds, particularly psittacines, can act as healthy carriers of PMV-1 virus and represent a significant source of contamination.
  • Contaminated Feed and Water: Feed and drinking water can become contaminated by droppings. Feed can be contaminated by infected wild birds, such as pigeons.
  • Poultry Products: Movement of poultry products, including dead birds and faeces (e.g., for fertilizer), can spread the virus.
  • Eggs: Eggs laid by infected breeders may occasionally contain the virus, though they rarely hatch. However, if broken in the hatchery, they can contaminate hatched chicks. Virus may also penetrate the shell after laying. Cracked or broken infected eggs serve as a virus source for chicks.
  • Wild Birds and Other Wildlife: Can spread the disease by infection or mechanical transfer. Preventing contact between poultry and wild birds (pigeons, waterfowl) is important for biosecurity. Ducks and geese may carry viral strains, generally nonpathogenic for chickens. Wild ducks often are the source of asymptomatic enteric lentogenic strains.
  • Vaccines: Live viruses used for vaccination are a reservoir because vaccinated poultry can replicate and disseminate them. Contamination of vaccines has also occurred.
  • Factors Influencing Spread:
  • Crowded conditions, like intensive broiler houses, facilitate rapid airborne spread and successive batches without proper cleaning.
  • If birds are not in direct contact (e.g., layers in cages), spread via faeces in feed/water may be slower.

Problem in your flock? Send photos of the birds and droppings on WhatsApp for a first opinion from Dr. Ibne Ali.

WhatsApp: 98715 84101
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