Serial passage is a virus

Virus

A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...

 attenuation

Attenuation

In physics, attenuation is the gradual loss in intensity of any kind of flux through a medium. For instance, sunlight is attenuated by dark glasses, X-rays are attenuated by lead, and light and sound are attenuated by water.In electrical engineering and telecommunications, attenuation affects the...

 technique developed originally by Louis Pasteur

Louis Pasteur

Louis Pasteur was a French chemist and microbiologist born in Dole. He is remembered for his remarkable breakthroughs in the causes and preventions of diseases. His discoveries reduced mortality from puerperal fever, and he created the first vaccine for rabies and anthrax. His experiments...

 in the 1880s. It is similar to selective breeding

Selective breeding

Selective breeding is the process of breeding plants and animals for particular genetic traits. Typically, strains that are selectively bred are domesticated, and the breeding is sometimes done by a professional breeder. Bred animals are known as breeds, while bred plants are known as varieties,...

, and can be used to create an attenuated strain of a virus to develop vaccine

Vaccine

A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins...

s, or to increase the virulence of a viral strain in order to create epidemic

Epidemic

In epidemiology, an epidemic , occurs when new cases of a certain disease, in a given human population, and during a given period, substantially exceed what is expected based on recent experience...

s.

The process involves infecting a series of host organisms with a virus. Each time the virus is given some time to incubate, and then the next host is infected with the incubated virus. The virus may mutate repeatedly into a form that is resistant to a wide variety of host immune system defenses, or a weaker strain may result.

Pasteur produced an early rabies

Rabies

Rabies is a viral disease that causes acute encephalitis in warm-blooded animals. It is zoonotic , most commonly by a bite from an infected animal. For a human, rabies is almost invariably fatal if post-exposure prophylaxis is not administered prior to the onset of severe symptoms...

 vaccine by using serial passage to transmit the virus until an attenuated developed which could be used to stimulate an immune response without causing a pathological infection.

Scientists have observed that non-virulent forms of HIV

HIV

Human immunodeficiency virus is a lentivirus that causes acquired immunodeficiency syndrome , a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive...

 can give rise to virulent strains after serial passage occurs in primate

Primate

A primate is a mammal of the order Primates , which contains prosimians and simians. Primates arose from ancestors that lived in the trees of tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment...

s.

Serial passage is also used in antimicrobial testing to determine how quickly an organism can acquire resistance to an antibiotic.

External links

• Brief mention of Pasteur's work with rabies serial passage