Pox diseases, Biology

Pox diseases


Small-pox in human beings and pox in a few animal species are closely related to each other. It is shown by the fact that the vaccine for the prevention of small pox consists of the virus of cow-pox collected from calves artificially infected with the disease. However, small pox has since been globally eradicated. Its other forms of animal pox viruses, viz. swine pox, horse pox, fowl pox and sheep pox with the possible exception of buffalo pox and campe pox are not transmissible to human beings. Pox diseases affecting human beings and animals have in all probability their origin in a  virus analogous to cow pox.


The pox viruses belong to the family Poxviridae and are classified into different genera, viz. Orthopoxvirus including vaccinia, cow-pox , camel-pox, buffalo-pox, ectromelia, horse-pox , monkey-pox and rabbit-pox viruses: Avipoxvirus including fowl-pox, canary-pox,pigeon-pox, quail-pox and turkey-pox; Capripoxvirus including sheep-pox, goat-pox and lumpy skin disease viruses; Leporipox including myxoma, rabbit fibroma, hare fibroma and squirrel fibroma viruses; Parapox including contagious ecthyma pseudo-cow-pox and Milker's nodule viruses. These viruses exhibit cross- reactivity with the production of cytoplasmic inclusion bodies.


Pox is transmitted by cutaneous inoculation or by smearing the infected material on an abraded surface of skin or on mucous membrane. In sheep, the infection is believed to be transmitted by inhalation since it is the lungs that are mostly affected. Pox viruses in a dry state can maintain their infectivity and virulence for several years at 4oC. In a wet state, the viruses are killed when exposed to 60oC for 10 min. The most effective and inexpensive chemical for inactivating pox viruses is potassium permanganate in a dilution of 1:1000. The majority of pox viruses can be grown on the chorio-allantoic membrane of fertile hen eggs. The lesions produced on the membrane are characteristic of a particular pox virus. Pox diseases can be easily reproduced in monkeys and rabbits.


The period of incubation in pox disease is 2 to 5 days. In cows, buffaloes, sheep and goats the disease usually commences with a rise in body temperature accompanied by marked constitutional disturbance. Five well marked stages of lesions viz. roseola stage consisting of diffused redness due to congestion and resembles a flea bite, which later turns into a raised hard area, the so-called  popular  stage. From the congested blood vessels in the papules, lymph exudes and vesicles are formed. The disease is now regarded as having reached the vesicular stage. In the next or the popular stage, the serous fluid becomes turbid with pus-producing organisms and the lesions are light yellow in appearance. The pustules dry up and form scabs in the last or the crust stage. The successive stages mentioned above appear at intervals of about 3 days and the full course run by the disease is of about 2 to 3 weeks. Recovered animals are usually resistant to further attacks of the disease.


Suitable vaccines are available or in offing against sheep pox, goat pox, swine pox, fowl pox, buffalo pox and camel pox.

Posted Date: 9/17/2012 9:22:35 AM | Location : United States







Related Discussions:- Pox diseases, Assignment Help, Ask Question on Pox diseases, Get Answer, Expert's Help, Pox diseases Discussions

Write discussion on Pox diseases
Your posts are moderated
Related Questions
describe each and every step in nutrition in animals?

Describe the appearance of a single E. coli colony. Why can it be considered genetically homogenous?

Q. What is the significance of magnesium for plants? What are the other major biological functions of magnesium? Magnesium is basically vital for plants because it is part of t

Alterations occurring in fruits and vegetables You may already be aware that fruits and vegetables vary greatly in their chemical composition. Though, some generalizations are

Define measuring body composition- Multiple isotope Dilution? Multiple isotope dilution (Total and extracellular body water): It is based on the principle that certain substanc

What is a biosphere? A biosphere is a set of all of the ecosystems of the planet.

explain in detail various types of epithelial tissue

Walking In the process of walking the motion of the two legs is coordinated so that one foot or the other is always in contact with ground. Walking is the best form of exercise

Segregation and Treatment of Dressing Waste In many departments waste is less and normally they do not have treatment facility for the bio-medical waste. In their case, interme

Q. Explain Natural History of Mitral Stenosis ? Untreated, mitral stenosis is a serious disease with observed 10-year mortality of 70-80 per cent in sy