The key difference between inactivated and recombinant flu vaccine is that inactivated flu vaccine is a vaccine produced either via cell-based or egg-based technology, while the recombinant flu vaccine is a vaccine produced using recombinant DNA technology.
Influenza, commonly known as flu, is a highly infectious disease caused by a virus. Influenza vaccines (flu vaccines and flu shots) are produced against the Influenza virus. Inactivated flu vaccine and recombinant flu vaccine are two types of influenza vaccines. Such vaccines are usually developed twice a year since the influenza virus changes rapidly. Fever, mild temporary muscle pains, and tiredness are few symptoms after influenza vaccination. Both vaccines come in inactive or weakened viral forms.
CONTENTS
1. Overview and Key Difference
2. What is an Inactivated Flu Vaccine
3. What is a Recombinant Flu Vaccine
4. Similarities Between Inactivated and Recombinant Flu Vaccine
5. Side by Side Comparison – Inactivated vs Recombinant Flu Vaccine in Tabular Form
6. Summary
What is an Inactivated Flu Vaccine?
The inactivated flu vaccine is a vaccine made using killed viruses. After vaccination, it usually takes up to two weeks to be protected. Inactivated flu vaccines are produced either egg-based or cell-based techniques. In egg-based vaccines, the virus is injected into fertilized chicken eggs and allowed to replicate. This fluid that contains the virus is used as the inactivated flu vaccines. The virus is either killed or weakened depending on the type of inactivated flu vaccine. Cell-based vaccines do not require chicken eggs. The virus is grown in animal cells.
There are three different types of inactivated flu vaccines. They are live attenuated influenza vaccine (LAIV), quadrivalent influenza vaccine (egg grown (QIVe), cell-based (QUIVc)) and adjuvanted trivalent vaccine (aTIV). The live attenuated influenza vaccine is given as a nasal spray, and it contains an inactive virus. The quadrivalent and trivalent vaccines are injected into the deltoid muscle or thigh muscle. It provides protection against four strains of the flu virus. The adjuvanted trivalent vaccine gives protection against three strains of the flu virus. The quadrivalent and trivalent vaccination during pregnancy will protect both the mother and newborn baby. However, a live attenuated vaccine is not given to pregnant women.
What is a Recombinant Flu Vaccine?
The recombinant flu vaccine is produced using recombinant DNA technology. These vaccines also contain inactive or weakened viruses. The recombinant flu vaccines are not egg-based and cells-based. Instead, the viruses are created synthetically.
Figure 01: Recombinant Flu Vaccine
Scientists obtain DNA to extract the surface protein called hemagglutinin of the influenza virus. Hemagglutinin is an antigen that triggers the immune system to create antibodies that specifically target the virus. This DNA involved in the production of flu virus hemagglutinin antigen is then combined with baculovirus. Baculovirus is a virus that infects invertebrates. Baculovirus helps to transport DNA instructions to make the hemagglutinin antigen into a host cell. When this recombinant virus enters Food and Drug Administration qualified host cell line, the cells start to produce the hemagglutinin antigen rapidly. These antigens are then purified and packed as recombinant flu vaccines. The recombinant flu vaccine is also injected into the deltoid muscle or thigh muscle.
What are the Similarities Between Inactivated and Recombinant Flu Vaccine?
- Both inactivated flu vaccine and recombinant flu vaccines are produced against the Influenza virus.
- They contain killed or weakened virus.
- Both vaccines are injected into the deltoid muscle or thigh muscle.
What is the Difference Between Inactivated and Recombinant Flu Vaccine?
Inactivated flu vaccine consists of virus grown in chicken eggs or animal cells, while recombinant flu vaccine is produced synthetically using recombinant DNA technology. So, this is the key difference between inactivated and recombinant flu vaccine. Moreover, recombinant flu vaccines are produced within a shorter time than inactivated flu vaccines.
The below infographic lists the differences between inactivated and recombinant flu vaccine in tabular form.
Summary – Inactivated vs Recombinant Flu Vaccine
Inactivated flu vaccine and recombinant flu vaccines are vaccines used against the Influenza virus. Influenza virus, also known as the flu, is a highly infectious disease caused by a virus. The inactivated flu vaccine is produced via cell-based or egg-based technology while recombinant flu vaccine is produced synthetically using recombinant DNA technology. The inactivated flu vaccine and recombinant flu vaccine are injected into the deltoid muscle or thigh muscle. However, a live attenuated flu vaccine is injected as a nasal spray. Thus, this summarizes the difference between inactivated and recombinant flu vaccine.
Reference:
1. Inactivated influenza (flu) vaccine. (2021, March 09). Retrieved May 12, 2021, from here.
2. Recombinant influenza (flu) vaccine. (2021, January 25). Retrieved May 12, 2021, from here.
Image Courtesy:
1. “Flu Vaccine: Reverse Genetics” By NIAID (CC BY 2.0) via Flickr