Designing efficacious norovirus vaccines remains a major challenge due to several factors:
(1) the extreme genetic variability within the norovirus family and within genogroups
(2) the rapid evolution of antigenically dissimilar pandemic GII.4 norovirus strains
(3) the lack of lasting immunity upon natural exposure to noroviruses in at least a proportion of the population.
It might be an ecosystem
Hope this helps
The aorta carries oxygenated blood from the right ventricle to the rest of the body for energy and metabolism.
<span>That is provided by the vestibular apparatus, which in each ear includes the utricle,saccule, and three semicircular canals. Hope this helped :)</span>
Answer:
Explanation:
because the earths core shakes when boiling under neath
