- - -

Avian influenza’s “internal factor" of selenium deficiency and an epidemic prevention strategy of "treating the cause”

Qu Yuan Qu Lai Qu Shaozhong

The spread of avian influenza all over the world can not be explained by external factors alone. According to dialectics, the internal factor is the basis and the external is the condition. The external factor can only act through the internal factor. What is the internal factor of avian influenza? Study shows that the internal factor of avian influenza is the consumption of selenium —the only element that has direct relation with viruses in the body of birds - in the peak period (autumn, winter and spring) of egg laying, which causes body imbalance and susceptibility to virus attack.

Let us examine the fact that the selenium composition in eggs is very high, with goose egg containing 336 mg/kg, duck egg 307 mg/kg, all reaching the selenium rich standard (280 mg/kg). The selenium composition of hen’s egg is 223 mg/kg, approaching selenium rich standard, and exceeding by far the selenium content of flour (47 mg/kg), rice (70 mg/kg) and beef (43 mg/kg). It can be said that birds are providing high selenium nurture to humans. However, the sources of selenium nurture for birds are not so good.

Taking chicken as an example, a hen can lay eggs 15-18 kg, and the egg/forage ratio should be between 2.6 and 2.8:1. If the selenium composition of egg can reach 233mg/kg, the selenium composition of forage should be 83mk/kg. (not including that consumed by chickens in their life and activity). But in some countries and regions deficient in selenium, it is difficult to reach this level (because the selenium in the soil is provided to animals through plants, and if soil is lacking selenium, feed grains are of course lacking selenium).

When income falls short of expenditure, e.g. high production of egg and low intake of selenium, the bird organism will lose its balance. As selenium is an important element needed by immune system, extreme lack of selenium will increase the possibility of being infected with avian influenza. This can be analyzed from macroscopic and microscopic view.

1. As seen from macroscopic view, the spread of avian influenza over the world is related to selenium deficiency

Fact: over 40 countries and regions are lacking selenium, including Europe, the USA, Canada, Asia and Southeast Asia. China is seriously deficient in selenium.

On the selenium distribution map of China, one can see a large selenium deficiency band running from the Northeast to the Southwest composed of 45 parts of provinces and municipalities. In addition, other areas are also short of selenium. There is only one third of the territory of our country where the soil reaches the normal critical value of 0.1mg/kg published internationally in terms of selenium composition and the remaining two thirds are selenium deficient area. The area with serious lack of selenium, (≤0.02mg/kg) accounts for 29% .

As bird forage is inexpensive, the materials of forage are usually taken from local resources, and the selenium in the food chain determines the selenium intake of local birds. Serious lack of selenium and high production of egg make hens lose their internal balance and cause a serious decline of resistance. The break-out and spread of avian influenza have coincides with these areas, and each time, this can be confirmed on the selenium distribution map of china. (See Fig. 1)