This is the documentation of the API for accessing the NIDSS Flu (nidss_flu) endpoint of the Delphi’s epidemiological data.

General topics not specific to any particular endpoint are discussed in the API overview. Such topics include: contributing, citing, and data licensing.

NIDSS Flu Data

Outpatient ILI from Taiwan’s National Infectious Disease Statistics System (NIDSS).

* Data is usually released on Tuesday


The base URL is:

See this documentation for details on specifying epiweeks, dates, and lists.



Parameter Description Type
epiweeks epiweeks list of epiweeks
regions regions list of region labels


Parameter Description Type
issues issues list of epiweeks
lag # weeks between each epiweek and its issue integer


  • If both issues and lag are specified, only issues is used. If neither is specified, the current issues are used.


Field Description Type
result result code: 1 = success, 2 = too many results, -2 = no results integer
epidata list of results array of objects
epidata[].release_date date when record was first published (yyyy-MM-dd) string
epidata[].region region string
epidata[].issue epiweek of publication integer
epidata[].epiweek epiweek during which the data was collected integer
epidata[].lag number of weeks between epiweek and issue integer
epidata[].visits total number of patients with ILI integer
epidata[].ili percent ILI float
message success or error message string

Example URLs

NIDSS Flu on 2015w01 (nationwide)

  "result": 1,
  "epidata": [
      "release_date": "2016-01-05",
      "region": "Nationwide",
      "issue": 201552,
      "epiweek": 201501,
      "lag": 51,
      "visits": 65685,
      "ili": 1.21
  "message": "success"

Code Samples

Libraries are available for JavaScript, Python, and R. The following samples show how to import the library and fetch national NIDSS Flu data for epiweeks 201440 and 201501-201510 (11 weeks total).

JavaScript (in a web browser)

<!-- Imports -->
<script src="delphi_epidata.js"></script>
<!-- Fetch data -->
  EpidataAsync.nidss_flu('nationwide', [201440, EpidataAsync.range(201501, 201510)]).then((res) => {
    console.log(res.result, res.message, res.epidata != null ? res.epidata.length : 0);


Optionally install the package using pip(env):

pip install delphi-epidata

Otherwise, place from this repo next to your python script.

# Import
from delphi_epidata import Epidata
# Fetch data
res = Epidata.nidss_flu(['nationwide'], [201440, Epidata.range(201501, 201510)])
print(res['result'], res['message'], len(res['epidata']))


# Import
# Fetch data
res <- Epidata$nidss_flu(list('nationwide'), list(201440, Epidata$range(201501, 201510)))
cat(paste(res$result, res$message, length(res$epidata), "\n"))