Be aware about Biowarfare

Introduction:

Biological warfare (BW) also known as germ warfare. It is the use of biological toxins or infectious agents such as bacteria, viruses and fungi with the intent to kill or incapacitate humans, animals or plants as an act of war. Biological warfare is defined as the deliberate use of microorganisms or toxins derived from living organisms to induce death or disease in humans, animals or plants.

Biological warfare has been talked about for several decades. Many of the larger countries have been producing and stockpiling pathogenic microorganisms, for potential use against the army of an enemy country with which they might go to war. Ex. The anthrax bacterium.

At the same time, several countries have been experimenting with and stockpiling microorganisms that can infect and destroy important staple food crops for certain countries, e.g., rice, potatoes, wheat, or beans, which could affect the availability of food and thereby survival of the people, or at least, their will to fight and prolong the war.

This type of agricultural biological warfare has revolved around important pathogens of such crops,

e.g., Magnaporthe grisea, the fungus causing the blast disease of rice, Phytophthora infestans, the oomycete causing the late blight of potato and Puccinia graminis, causing the rust diseases of wheat and other small grains.

Biolgical weapons

It is also called germ weapon/ bio-weapons/ biological threat agents or bio-agents. Biological weapons are living organisms or replicating entities (viruses, which are not universally considered "alive") that reproduce or replicate within their host victims. Biological warfare agents

1) Bacteria — Xanthomonas oryzae pv. oryzicola (Rice bacterial blight), anthrax, plague.

2) Rickettsiae — Typhus and Q fever.

3) Viruses— TBRV Virus (Tomato Black Ring), Ebola virus

4) Fungi— Rice blast, cereal rust, wheat smut, and potato blight.

Toxins –

Poisons that can be weaponized after extraction from snakes, insects, spiders, marine organisms, plants, bacteria, fungi, and animals. An example of a toxin is ricin, which is derived from the seed of the castor bean. It is ease of production, ease of dissemination, low infective dose, and short incubation period.

This is difficult to diagnose in early stages, potential for high injury & mortality rates, high infectivity, short life cycle, stability in the environment, lack of availability of cost-effective treatments, absence of genetic resistance, potential to disrupt exports and effect economy.

Plant pathogens may be used as Bioweapons against India -

1) Viruses such as Rice tungro bacilliform virus with four variables isolated from South Asia. Rice tungro spherical virus whose Indian isolate is different from the South-East Asian isolates.

2) Cotton leaf curl virus which causes severe damage in Pakistan but has a limited distribution in India.

3) Groundnut bud necrosis virus having a wide host range.

4) Banana bunchy top virus with five identified strains.

5) Tobacco streak virus, citrus tristeza virus and Mungbean yellow mosaic virus with several strains reported.

6) Cereal rusts caused by Puccinia graminis (whose spores are air-borne of which a number of virulent pathotypes are known).

7)  Rice blast (Pyricularia oryzae, where a high degree of variability has been reported), Bulkholderia solanacearum (race 2 of which is not known in India).

8) Xanthomonas campestris pv. malvacearum (of which the most virulent pathovar in Africa – XcmN 89 is not known in India.

Pest (Insect)

1) Bemisia tabaci, (a highly polyphagous pest which attacks >600 host plant species has 16 known biotypes).

2) Brown plant hopper (Nilaparvata lugens, where biotypes from India differ from those in other Asian countries).

3) Rice gall midge (Orseolia oryzae, has six biotypes known from India),

4) Red flour beetle (Tribolium castaneum, whose strains show variability in level of pesticide resistance).

5) Races of nematodes - Meloidogyne incognita, M. javanica/ M. arenaria, Heterodera avenae.

How the biological warfare is differing from the bioterrorism?

The Biological warfare is usually directed against enemy armies and its purpose is to incapacitate or kill enemy soldiers.

In Bioterrorism the purpose is to frighten and terrorize civilian populations, although casualties in large numbers may or may not occur.

How Biological Agents Are Delivered?

Delivery of Biological Agents:-

 

Article compiled by Mr. Amol Vijay Shitole (Ph.D. Scholar)

Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola (M.S.)