It is interesting to see how different inventions came about during the course of human history, how they have had an impact on other industries of society and can give rise to amazing improvements within it.

This is the example of nebulization or atomization of a liquid.

When we speak of nebulization of a liquid, we mean forcing it through a small space so that it is subjected to pressure.

This process can be actuated in different ways: mechanically or by means of a propellant.

It was in 1899 that the inventors Helbing and Pertsch patented the first pressurized aerosols that used methyl chloride and ethyl chloride as propellants.

Later, during the twentieth century, improved results were achieved in this field, with the Norwegian engineer Erik Rotheim patenting the first aerosol with a valve, giving rise to the current concept of an aerosol.

Original drawings of the first spray aerosol, designed by Norwegian engineer Erik Rotheim in 1926 (Source: Wikipedia).

During the Second World War, great progress was made in this field for several reasons.

The first was directly linked to the development of aerosols that were capable of spraying an insecticide that would protect the soldiers against insects.

The second was due to the reduction in the population that was able to work in the fields and the need to industrialize agriculture and protect crops against a variety of infestations. 

The image below was released by the Research agency of the United States Department of Agriculture. 

Design of the first functional aerosols for the Second World War (Source: Wikipedia).  

In light of the industrialization of poultry farming and, together with the appearance of the first pandemics associated with Newcastle disease and avian influenza, there was a growing need to protect the birds.

The first vaccines, which were injectable, and therefore contained killed virus together with an adjuvant and were applied individually, led to the first live attenuated vaccines and the need for application on a broader scale.

Hence, from the nineteen fifties onwards, work was started on different routes of administration of the vaccines.

Hitchner et al., in 1954, were the first to use a Newcastle vaccine for intranasal spray administration.

Currently, different combinations of pressures are applied and the nozzles can be tweaked for better adjustment to the requirements of the different diseases, thereby improving the administration of the vaccine.

Depending on whether vaccination is being carried out on the farm or in the hatchery, the devices used can vary and can be mobile or, conversely, can be fixed on a conveyer belt inside the hatchery.

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