Date Range
Use this slider to filter the data based on the sample date. This may include inferred dates for ancestral nodes in the tree, and thus the date range here can be wider than the sample collection range.
1969-04-26
2024-12-01
Color By
Change the metadata field which the visualisation is coloured by.
The phylogeny, map and frequencies panel (if available) will all be coloured in a consistent fashion.
The phylogeny, map and frequencies panel (if available) will all be coloured in a consistent fashion.
Region
Filter Data
Use this box to filter the displayed data based upon filtering criteria.
For instance, start typing a country's name to filter the data accordingly.
Data is filtered by forming a union of selected values within each category, and then taking the intersection between categories (if more than one category is selected).
Scroll to the bottom of the main page (under the data visualisation) to see an expanded display of filters and available values.
Filter options prefixed with "(M)" are filters specific to the Measurements panel. They will have no effect on the phylogeny tree or other panels.
Data is filtered by forming a union of selected values within each category, and then taking the intersection between categories (if more than one category is selected).
Scroll to the bottom of the main page (under the data visualisation) to see an expanded display of filters and available values.
Filter options prefixed with "(M)" are filters specific to the Measurements panel. They will have no effect on the phylogeny tree or other panels.
Type filter query here...
Tree
This panel displays the evolutionary relationships among samples, illustrating their genetic relatedness and inferred ancestry.
The exact options available depend on the dataset and specific analysis performed.
If Branch Length is available, you can choose to display the tree branches in terms of (nucleotide) divergence or (inferred) time. It is often helpful to toggle on confidence intervals to gauge the uncertainty in the reconstruction of internal node dates.
The exact options available depend on the dataset and specific analysis performed.
If Branch Length is available, you can choose to display the tree branches in terms of (nucleotide) divergence or (inferred) time. It is often helpful to toggle on confidence intervals to gauge the uncertainty in the reconstruction of internal node dates.
none
Sample Name
Select...
Map
This panel displays the geographical distribution of samples.
The geographic resolution chooses the metadata values which define where samples are placed on the map. This can be the same as the selected color-by but is often not!
The geographic resolution chooses the metadata values which define where samples are placed on the map. This can be the same as the selected color-by but is often not!
country
Entropy
This panel displays the observed diversity across the current genome or a selected CDS. All options are in the panel itself.
Animation Options
Change various options relating to how the animation proceeds.
Display
Control whether to show the tree and the map side-by-side (grid) or expanded (full).
Language
English
Real-time tracking of influenza A/H9N2 virus evolution
Built with nextstrain/avian-flu. Maintained by Louise Moncla. Data updated 2025-03-20. Enabled by data from 
.Showing 2897 of 2897 genomes sampled between Dec 1976 and Nov 2024.
Phylogeny
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