Early childhood flu exposure may determine immunity in later life, but not all strains are equal: scientists
- People infected with H1N1 can fight off the H3N2 strain but the reverse is not necessarily true, finds paper
- Influenza immunity findings add weight to the argument that children should be vaccinated but the success of flu shots depends on several factors
Immune defence against general flu may depend on the specific type of viral strain a person first came into contact with in the early days of their life, according to a new study.
But getting H3N2 first could not provide similar protection against H1N1.
“Humans typically encounter only a limited number of viruses early in childhood and therefore have somewhat narrow immune memory skewed toward viral strains encountered early in life,” said Hensley and colleagues in a peer-reviewed paper published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS) this month.
H3N2 has been the dominant influenza strain in circulation on our planet over the past decade. It shares some similarities with H1N1, such as the ability to infect pigs. But there was a genetic gap between the viruses wide enough for scientists to put them in different groups.