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
K e to s i s It is also known as acetonemia in bovines or pregnancy toxaemia in sheep and is associated with ketonemia, ketonuria and low blood glucose. E t iol

BEE DISEASES - Suffer from nosema diseases caused by Nosema apis. SILK WORM DISEASES - Pebrine disease caused by Nosema.

Anton van Leeuwenhoek was the first to propose placing microorganisms into the Kingdom Monera. True or False

Define Aerobic Exercise or Aerobic Energy System? To produce necessary energy, the body uses an aerobic pathway and an anaerobic pathway. Exercise that relies heavily on oxygen

Q. Illustrate Omega Taxonomy? After synthesising a basic classification, the taxonomist can attempt to improve upon it. Therefore, the observed facts are interpreted in Omega t

What do you understand by Arthropodization? Many of the traits that we consider unique to the Arthropoda may not be independent traits. Instead, they may be the consequence of

Q. Causes of reduced Serum HDL levels? Possible causes of reduced Serum HDL levels: - Cigarette smoking - Hypertriglyceridemia - Obesity - Genetic factors - Lack

Define Nutrition Management and Feeding the Premature Infant There are numerous nutritional risk factors in premature infants. These include: Elevated metabolic rate, th

Q. What are target organs of the hormones? Target tissues, Target organs and target cells are those specific organs, cells and tissues upon which each hormone produces and acts

Explain the Transfer from liquid medium to solid media? Here the steps involved include: 1. Inoculating loop is sterilized by incineration and allowed to cool, as described