An equine respiratory enterovirus. Some biological and physical properties.

This research explores the impact of an equine respiratory virus on animals (monkeys, rabbits, and guinea pigs), noting its replication process and difficulty in its isolation from guinea pig tissues. The study also recorded the virus’ effect on a human volunteer and its reaction to varying pH levels.

Animal Experimentation

In the above-mentioned experiments, the researchers inoculated three kinds of animals intranasally with the equine respiratory virus, noted to be:

• Monkeys
• Rabbits
• Guinea pigs

After inoculation, the animals were killed at distinct intervals and attempts were made to isolate the virus from tissue culture extracted from the homogenized tissues and organs. The results were as follows:

• All three species were found to be susceptible to the virus, with reproduction of the virus occurring in the respiratory tract and associated lymph glands.
• The virus was least readily isolated from guinea pig tissues indicating a lesser susceptibility or reproduction capability in this species.

Additionally, viraemia (presence of viruses in the blood) was identified in monkeys and rabbits, but was minimally detected in the guinea pigs. The virus was also found in the urine and kidney cultures of some animals, which had by then developed antibodies against the virus.

Human Experimentation

An individual volunteered to be intranasally inoculated with the virus as well, and the results were:

• The volunteer developed severe pharyngitis and swelling of the pharyngeal lymph glands.
• Viraemia occurred, accompanied by fever, and the condition lasted for four days.

Virus Stability

The final part of the research was understanding the stability of the virus under varying conditions. It was found that:

• The virus was unstable at a pH level of 5.0 and below. This indicates that the virus is active and can replicate in environments with a pH higher than 5.0.
• The stability of the virus in distilled water was not increased by the addition of magnesium chloride. This tells us that the virus is not dependent on this specific chemical compound for its stability.