Rubella vaccine

Schedule

There are two main ways to deliver the rubella vaccine. The first is initially efforts to immunize all people less than forty years old followed by providing a first dose of vaccine between 9 and 12 months of age. Otherwise simply women of childbearing age can be vaccinated.^[1]

While only one dose is necessary two doses are often given as it usually comes mixed with the measles vaccine.^[1]

Pregnancy

Women who are planning to become pregnant are recommended to have rubella immunity beforehand, as the virus has a potential to cause miscarriage or serious birth defects.^[5] Immunity may be verified by pre-pregnancy blood test, and it is recommended that those with negative results should refrain from getting pregnant for at least a month after receiving the vaccine.^[5]

The vaccine theoretically should not be given during pregnancy. However, more than a thousand women have been given the vaccine when they did not realize that they were pregnant and no negative outcomes occurred. Testing for pregnancy before giving the vaccine is not needed.^[1]

If a low titre is found during pregnancy, the vaccine should be given after delivery. It is also advisable to avoid becoming pregnant for the four weeks following the administration of the vaccine.^[6]

HPV-77

The first successful strain to be used was the HPV-77, prepared by passing the virus through the cells of an African green monkey kidney 77 times. The efforts to develop the vaccine were conducted by a team of researchers at the National Institutes of Health's Division of Biologics Standards. Led by Harry M. Meyer and Paul D. Parkman, the team included Hope E. Hopps,^[8] Ruth L. Kirschstein, and Rudyard Wallace among others, the team began serious work on the vaccine with the arrival of a major rubella epidemic in the United States in 1964. Prior to arriving at the National Institutes of Health (NIH), Parkman had been working on isolating the rubella virus for the Army. He joined the laboratory of Harry Meyer.^[9]

Parkman, Meyer, and the team from the NIH tested the vaccine at the Children's Colony in Conway, Arkansas in 1965 while a rubella epidemic still raged across the United States.^[10] This residential home provided care for children with cognitive disabilities and children who were ill. The ability to isolate children in their cabins and control access to the children made it an ideal location for testing a vaccine without starting an epidemic of rubella. Each of the children's parents provided consent for the participation in the trial.^[9]

In June 1969, the NIH issued the first license for commercial production of the rubella vaccine to the pharmaceutical company Merck Sharp & Dohme.^[11] This vaccine made use of the HPV77 rubella strain and was produced in duck embryo cells. This version of the rubella vaccine was in use for only a few years before the introduction of the combined measles, mumps, and rubella (MMR) vaccine in 1971.^[12]

RA 27/3

Most of the modern Rubella vaccines (including the combination vaccine MMR) contain the RA 27/3 strain,^[13] which was developed by Stanley Plotkin and Leonard Hayflick at the Wistar Institute in Philadelphia. The vaccine was attenuated and prepared in the WI-38 normal human diploid cell strain which was developed by Hayflick^[14][15] and gifted to Plotkin by him.

In order to isolate the virus, instead of taking swab samples from the throats of infected patients, which could have been contaminated with other resident viruses, Plotkin decided to utilize aborted fetuses provided by the department of Obstetrics and Gynecology of the Hospital of the University of Pennsylvania. At the time, abortion was illegal in most of the United States (including Pennsylvania), but doctors were allowed to perform "therapeutic abortions" when the life of the woman was in danger. Some started to perform them also on women infected with rubella.^[16] Several dozens of aborted fetuses were collected and studied by Plotkin. The kidney tissue from fetus 27 produced the strain that was used to develop the attenuated rubella vaccine. The name RA 27/3 refers to "Rubella Abortus", 27th fetus, 3rd organ to be harvested (the kidney).^[17]

The vaccine was first approved by the UK in 1970. The strain became the preferred vaccine used by pharmaceutical companies over the HPV-77, due to several considerations, including its higher immunogenicity; Merck made it its mainstay rubella vaccine in 1979.^[7]

Parkman and his team did not monetize their patents, wanting the vaccine to be freely available.^[18]