Would you rather have one shot or multiple shots? Unless you are an aichmophiliac, your answer would probably be one.
Aichmophilia is the obsessive interest in sharp or pointy objects. Not sharp like a hounds-tooth jacket, but sharp like knives, swords, and needles. For everyone who does not have aichmophilia, the U.S. Food and Drug Administration (FDA) has just approved a combination “diphtheria-tetanus-pertussis-hepatitis B-poliomyelitis-invasive haemophilus influenza type B disease” vaccine.
Of course, this name wouldn’t quite flow off the tongue and the acronym DTPHPHIB spells absolutely nothing with far too many consonants. Therefore, Sanofi and Merck, who developed the vaccine in a joint-partnership, are calling this combination vaccine Vaxelis.
Vaxelis is a hexavalent vaccine, which is a heckuva lot of valents. The prefix hexa- means six. So, a hexapod is an insect with 6 legs. A hexagon is a shape with 6 sides. A a hexa-doughnut would be a doughnut with 6 of something.
A vaccine’s valence is the number of different types of antigens the vaccine contains. An antigen is something that stimulates your immune system to react. Usually, for a vaccine, it is either a part of or the entire body of a virus or bacteria. The vaccine essentially says, “hey, check this out immune system. This is what you want to be ready to defend against.” Therefore, a vaccine isn’t a mysterious concoction but a way of exposing you to a microorganism without you actually getting the disease.
The valence of a vaccine then translates into the number of different types of microorganisms that the vaccine can protect you against. A monovalent vaccine has a single type of antigen and stimulates your immune system to ward off one type of microbe. A bivalent has two and protects against two. A trivalent vaccine like the measles-mumps-rubella (MMR) vaccine, has three. A quadrivalent has four. A pentavalent vaccine has five like the diphtheria, tetanus, pertussis (whole cell), hepatitis B (rDNA) and Haemophilus influenzae type B conjugate vaccine. This is often referred to as the DTP-HepB-Hib vaccine, which is much easier to say and sounds a bit like a cheer.
Therefore, the hexavalent Vaxelis is designed to offer protection against six diseases and significantly reduce the number of shots you need to get as a little kid. Thus, to be fully immunized against diphtheria, tetanus, pertussis, hepatitis B, polio, and invasive haemophilus influenza type B disease, you will only have to get three doses of Vaxelis between your turning 6 weeks and turning 5 years old. If you are already older than 5 and have been through all the traditional shots, sorry. If you are going to drift past the 6 week to 5 years old age range into old age before 2020, you are also out of luck. Sanofi and Merck won’t be able to get their production lines in place to offer the vaccine widely until at earliest 2020.
That’s not the case in the European Union or EU, where Vaxelis was approved by regulators about 3 years ago to reach the market in early 2016. Vaxelis wasn’t even the first hexavalent vaccine to have been marketed in the EU with Sanofi’s Hexyon and GlaxoSmithKline’s Infanrix Hexa having already reached the market back then.
This hexavalent vaccine is the latest of ongoing efforts to reduce the number of shots kids have to get. Besides being welcome by those who are not aichmophiliacs, reducing the number of required shots can help simplify somewhat the operations of a doctor’s offices and also simplify supply chains by reducing the number of vaccine that need to be ordered, stored, and transported. Typically, a combination vaccine with more antigens doesn’t mean that the doctor will have to use a giant syringe. A single Vaxelis injection should look like a typical single injection that is delivered into a muscle in the arm or thigh, just with a greater variety of antigens.