An image warning recently vaccinated people to stay away from babies, young children, pregnant women, immunocompromised people, the elderly, and terminally ill people for at least two weeks has been shared over 1,000 times on Facebook.
However, the post exaggerates the risk posed by vaccines to people with a compromised immune system, and the other groups mentioned by the post are not listed as at risk in public health guidelines. Public Health England says that “vaccination of close contacts of vulnerable people has a major benefit by reducing the risk of exposure to wild-type infection”.
Vaccines can be divided into two main types: live vaccines and inactivated vaccines. Inactivated vaccines contain either a killed version of the bacteria or virus, or a harmless bit of it, and cannot cause the disease they protect against. Live vaccines contain a “weakened version” of the bacteria or virus and do not cause the disease in healthy people.
That said, according to the Vaccine Knowledge Project at the University of Oxford, “live vaccines are not suitable for people whose immune system does not work, either due to drug treatment or underlying illness.”
“This is because the weakened viruses or bacteria can multiply too much and might cause disease in these people.”
It told us that the only real risk to immunocompromised people from live vaccines is to those with T-cell immunodeficiency. This is where the body has a very low number of t-cells (a type of white blood cell). This could be because someone has HIV, is undergoing cancer treatment or has a rare genetic disorder.
Public Health England (PHE) advises those close to immunocompromised people to have their full schedule of vaccines, and that they should be offered extra immunisations. It says: “this will reduce the risk of exposure of vulnerable individuals to the serious consequences of vaccine-preventable infections.” It also advises that those in close contact with immunocompromised people have their required vaccines to reduce “the risk of exposure to wild-type infection.”
For babies, young children, the elderly and pregnant women, PHE provides no guidelines or warnings on interacting with people who have recently received live vaccinations. It also says that having a pregnant household member does not mean someone shouldn’t get the routine vaccinations. Like the Vaccine Knowledge Project, the only group it says is vulnerable to the transmission of live vaccines is those with immunodeficiency.
For those who may have temporarily weakened immune systems, like those receiving chemotherapy or bone marrow transplants, it is recommended to avoid receiving live vaccines for a period after treatment.
Cancer Research UK recommends that people receiving chemotherapy avoid contact with people who have recently had oral vaccines or flu vaccine nasal spray. It says PHE advises people getting chemotherapy to avoid contact with people who have had the chicken pox and have developed a rash, and only if that rash can’t be covered. Cancer Research UK also says to take precautions when changing the nappies of babies who have received the rotavirus vaccine. However, it also reiterates that it's usually safe to be in contact with adults who have had live vaccines as injections, and children who have had most of the standard childhood immunisations.
People who receive a stem cell transplant are kept in isolation after their treatment while their new immune systems develop. Lead Nurse Hayley Leonard, at Anthony Nolan, the blood cancer charity, told us: “There is a theoretical risk that when you've had a live vaccine you could secrete the virus before you become immune and therefore infect an immunocompromised person [who has had a stem cell transplant]. I'm sure the risk is tiny but yes [transplant] centres might advise this.”