pyerviss

Unofficial Python API to ERVISS, the European Respiratory Virus Surveillance Summary

Weekly ILI, ARI and SARI rates for EU/EEA countries as pandas DataFrames, from ECDC's ERVISS data, with ILI and ARI history back to 2014.

Disclaimer: pyerviss is an independent, unofficial project. It is not affiliated with, endorsed by, or maintained by the European Centre for Disease Prevention and Control (ECDC) or ERVISS. The data is mirrored from ECDC's public repository and processed here (units are harmonized, history is added from other sources, and rows ECDC later removes are kept), so it can differ from the official figures. For official data, see erviss.org.

Installation

pip install pyerviss

Requires Python 3.10+.

Usage

import pyerviss as pv

# ILI rates for Italy and Malta (names or ISO2 codes) in the 2024/25 season
df = pv.get_ili(countries=["Italy", "MT"], season="2024/25", age_groups="total")

# SARI rates for people aged 65+ between two dates (weeks or dates, inclusive)
df = pv.get_sari(start="2024-10-01", end="2025-03-31", age_groups="65+")

# ARI rates for all countries
df = pv.get_ari()

Every query returns one row per country, week and age group:

• date is the last day (Sunday) of the ISO week.
• A season such as "2024/25" runs from 2024-W40 to 2025-W39.
• value is a rate per 100,000 of denominator: population, consultations or admissions (see Units).
• Data before 2022-W25 is only available for the "total" age group.

Finding out what is available:

pv.coverage("ili")         # per country: first/last week, number of weeks, age groups
pv.list_countries("sari")  # countries with SARI data
pv.list_seasons()          # ["2014/15", ..., "2025/26"]
pv.latest_week()           # most recent week with data, e.g. "2026-W38"

Data is downloaded on first use and cached locally (~/.cache/pyerviss on Linux), then checked for updates at most once an hour. Without a connection, the cached copy is used. pv.update_data() checks for updates now and pv.clear_cache() removes the cache.

Data

data/ mirrors ILI, ARI and SARI rates from ECDC's Respiratory_viruses_weekly_data, synced daily and merged cumulatively (rows ECDC removes are kept). ILI and ARI (total age group) also go back to 2014-W40, imported once from the RespiCast ERVISS snapshots of 2024-10-11 for weeks ECDC no longer publishes.

Units

Every value is a rate per 100,000 of the row's denominator, which differs by country:

Rates with different denominators are not directly comparable. Slovakia's SARI data is based on ICU admissions only. The sync fails if a country's values change scale by orders of magnitude, which would indicate a unit change upstream.

Credits

Data from the European Centre for Disease Prevention and Control (ECDC), European Respiratory Virus Surveillance Summary (ERVISS), published in EU-ECDC/Respiratory_viruses_weekly_data; see that repository for the data's terms of use. Historical ILI and ARI data via the European RespiCast Hub.

License

The code is released under the MIT License.