FluView Clinical

Attribute Details
Source Name fluview_clinical
Data Source United States Centers for Disease Control and Prevention (CDC)
Geographic Levels National, Department of Health & Human Services (HHS) Regions, Census Divisions, State (see Geographic Codes)
Temporal Granularity Weekly (Epiweek)
Reporting Cadence Weekly (typically Fridays)
Temporal Scope Start 2016w40
License Publicly Accessible US Government

Overview

This data source provides age-stratified clinical data based on laboratory-confirmed influenza reports from the US FluView dashboard.

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

Table of contents

  1. Estimation
    1. Percentages
  2. Lag and Backfill
  3. The API
    1. Parameters
      1. Required
      2. Optional
    2. Response
  4. Example URLs
    1. FluView Clinical on 2020w01 (national)
  5. Code Samples
    1. Legacy Clients

Estimation

Values are sourced directly from the CDC’s NREVSS (National Respiratory and Enteric Virus Surveillance System) clinical laboratories.

The metrics consist of weekly counts of influenza specimens (total tested and total positive for types A and B) and their corresponding positivity rates. Unlike the syndromic ILI data in the FluView endpoint, these metrics provide laboratory confirmation of influenza circulation.

Percentages

The CDC calculates three percentage metrics:

  • percent_positive: Percentage of total specimens that tested positive for influenza (A or B)
  • percent_a: Percentage of total specimens that tested positive for influenza A
  • percent_b: Percentage of total specimens that tested positive for influenza B

Lag and Backfill

The data is preliminary and subject to revision. Clinical labs may report data late or correct previously reported data. The issues and lag parameters allow access to historical versions of the data.

The API

The base URL is: https://api.delphi.cmu.edu/epidata/fluview_clinical/

Parameters

Required

Parameter Description Type
epiweeks epiweeks (see Date Formats) list of epiweeks
regions regions list of region labels: nat, states, hhs1-hhs10, cen1-cen9 (see Geographic Codes)

Optional

Parameter Description Type
issues issues (see Date Formats) list of epiweeks
lag # weeks between each epiweek and its issue integer

Notes:

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

Response

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 data was released string
epidata[].region region identifier string
epidata[].issue epiweek of publication integer
epidata[].epiweek epiweek for which data is valid integer
epidata[].lag number of weeks between epiweek and issue integer
epidata[].total_specimens total number of specimens tested integer
epidata[].total_a total specimens positive for influenza A integer
epidata[].total_b total specimens positive for influenza B integer
epidata[].percent_positive percentage of specimens testing positive for influenza float
epidata[].percent_a percentage of specimens testing positive for influenza A float
epidata[].percent_b percentage of specimens testing positive for influenza B float
message success or error message string

Example URLs

FluView Clinical on 2020w01 (national)

https://api.delphi.cmu.edu/epidata/fluview_clinical/?regions=nat&epiweeks=202001

{
  "result": 1,
  "epidata": [
    {
      "release_date": "2021-10-08",
      "region": "nat",
      "issue": 202139,
      "epiweek": 202001,
      "lag": 91,
      "total_specimens": 65177,
      "total_a": 5645,
      "total_b": 9664,
      "percent_positive": 23.4883,
      "percent_a": 8.66103,
      "percent_b": 14.8273
    }
  ],
  "message": "success"
}

Code Samples

Libraries are available for R and Python. The following samples show how to import the library and fetch national FluView Clinical data for epiweeks 201601-201701.

Install the package using pip:

pip install -e "git+https://github.com/cmu-delphi/epidatpy.git#egg=epidatpy"

# Import
from epidatpy import CovidcastEpidata, EpiDataContext, EpiRange
# Fetch data
res = Epidata.fluview_clinical(['nat'], [Epidata.range(201601, 201701)])
print(res['result'], res['message'], len(res['epidata']))

library(epidatr)
# Fetch data
res <- pub_fluview_clinical(regions = "nat", epiweeks =  epirange(201601, 201701))
print(res)

Legacy Clients

We recommend using the modern client libraries mentioned above. Legacy clients are also available for Python, R, and JavaScript.

Optionally install the package using pip(env):

pip install delphi-epidata

Place delphi_epidata.py from this repo next to your python script.

# Import
from delphi_epidata import Epidata
# Fetch data
res = Epidata.fluview_clinical(['nat'], [Epidata.range(201601, 201701)])
print(res['result'], res['message'], len(res['epidata']))

Place delphi_epidata.R from this repo next to your R script.

source("delphi_epidata.R")
# Fetch data
res <- Epidata$fluview_clinical(regions = list("nat"), epiweeks = list(Epidata$range(201601, 201701)))
print(res$message)
print(length(res$epidata))

  <!-- Imports -->
  <script src="delphi_epidata.js"></script>
  <!-- Fetch data -->
  <script>
    EpidataAsync.fluview_clinical('nat', [EpidataAsync.range(201601, 201701)]).then((res) => {
      console.log(res.result, res.message, res.epidata != null ? res.epidata.length : 0);
    });
  </script>