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Notices and Updates

For updates, including data corrections, new aggregates, and any other changes to the API, we encourage you to subscribe to our COVID-19 API mailing list.

Introducing Version 2 API and the Wave 12 and Wave 13 aggregates

We are excited to share with you that a new version of the API is available! The Version 2 API optimizes performance of the API. The new Version 2 API is accessed through a small change in the URL - you will need to change “api” to “apiv2” For example: https://covidmap.umd.edu/apiv2/resources?indicator=covid&type=daily&country=Brazil&daterange=20200501-20220518

The returned JSON will use a slightly different set of keys: country, (region), survey_date, indicator, sample_size, pct, se, (pct_unw, se_unw) where the indicator names will now appear in the returned keys of JSON. Wildcard(*) is temporarily not supported, so the URL must contain specified indicator names, and country and region if applicable.

The V1 API will remain in production and support requests for indicators from Wave 11 and prior. The V2 API is backwards compatible and contains all indicators from previous waves as well as any indicators from Wave 12 and forward.

As Wave 13 launched on Jan 30, 2022, NEW aggregate indicators for Wave 12 and 13 are available now! These new indicators are only available in V2 API. Check out the new indicators in the vaccine and parenting category

Incorrect Wave 12 data release (Dec 19,2021 - Jan 10, 2022)

Wave 12 of the COVID-19 Trends and Impact Survey (CTIS) launched December 19, 2021. However, we noticed some pipeline issues and worked on the fix. All the data product were up-to-date after 01/10/2022. Thus, any collected data of wave 12 between 12/19 and 01/10 should be void and recollected again.

All notices

Date Notice
02/21/2022 As wave 13 launched on Jan 30, 2022, NEW aggregated indicators for wave 12 and 13 are available now! Checkout the new indicators in vaccine and parenting category!
12/19/2021 Wave 12 of the COVID-19 Trends and Impact Survey (CTIS) launched December 19, 2021. However, we noticed some pipeline issues and worked on the fix. All the data product were up-to-date after 01/10/2022. Thus, any collected data of wave 12 between 12/19 and 01/10 should be void and recollected again.
12/17/2021 On Dec 17th, 2021, Data collection was paused for several hours for all countries due to a system update. Be cautious about the lower sample size when using any of the data product on that day.
08/17/2021 New indicators from questions C13a and C0a are available now. The newly added 6 indicators starting 05/20/2021 can be found in the indicator categories of behavior
07/20/2021 New indicators from questions V18a and V18b are available now. The newly added 24 indicators starting 05/20/2021 can be found in the indicator categories of vaccine
06/29/2021 New aggregate indicators for survey version 11 are available now. The newly added 63 indicators starting 05/20/2021 can be found in the indicator categories of symptoms,module, and vaccine
06/07/2021 A new version of the survey (V11) was launched on 05/20/2021. This was a major revision of the survey, and we have observed discontinuities in the covid and flu aggregate indicators as a result of these revisions.

To test the effects of the changes to the survey, 20% of respondents have been receiving the old version of the survey (V10) and 80% have been receiving the new version of the survey (V11) since its launch on 05/20/2021. To enable monitoring of the observed discontinuities in the existing covid and flu aggregate indicators, we added two new aggregate indicators to the API, cli_w11 and ili_w11, which are calculated using the same methodology. These new indicators (cli_w11 and ili_w11) will be calculated using the 80% of respondents receiving V11 while the existing indicators (covid and flu) will be backfilled to be calculated using the 20% of respondents receiving V10. The new and existing indicators will be backfilled to 05/20/2021 and will continue to be reported in this manner until at least 06/17/21.

There is also a blog post about the wave 10 and wave 11 CLI trend break here.
06/03/2021 A new version of the survey (V11) was launched on 05/20/2021. This was a major revision of the survey, and as a result of these revisions, we have observed discontinuities in our covid (COVID-like illness) and flu (influenza-like illness) aggregate indicators that are reported in our API.
To test the effects of the changes to the survey, 20% of respondents have been receiving the old version of the survey (V10) and 80% have been receiving the new version of the survey (V11) since its launch on 05/20/2021. To enable monitoring of the observed discontinuities in the existing covid and flu aggregate indicators, we will be adding two new aggregate indicators to the API,which are calculated using the same methodology. These new indicators (cli_w11 and ili_w11) will be calculated using the 80% of respondents receiving V11 while the existing indicators (covid and flu) will be changed to be calculated using only the 20% of respondents receiving V10. The new and existing indicators will be backfilled to 05/20/2021 and will continue to be reported in this manner until at least 06/17/21.
We are continuing analyses of these discontinuities, but in the interim, we encourage users of the aggregate data to re-pull the backfilled “covid” and “flu”indicators when they become available. To be notified when they are ready, please subscribe to our survey listserv. We encourage both users of the aggregate data as well as microdata users to use caution for comparing data collected after 05/20/2021 to data collected before 05/20/2021 for other indicators as well. We also encourage microdata users to use data from the 20% of the respondents who have been receiving the old version of the survey (V10) to evaluate the effects of the survey revisions for the survey questions used in their analyses.
05/20/2021 We have implemented an updated for aggregate indicators in the UMD Open Data API. They are vaccinated_appointment_or_accept, appointment_or_accept_covid_vaccine, accept_covid_vaccine_no_appointment, appointment_not_vaccinated, vaccine_tried, activity_large_event, activity_public_transit, activity_restaurant_bar, activity_shop, activity_spent_time, activity_work_outside_home and an update for the Item # for tested_positive_recent,tested_positive_recent,and hesitant_sideeffects.
05/11/2021 We have implemented an updated for aggregate indicators in the UMD Open Data API. They are flu_vaccine_thisyr, flu_vaccine_lastyr, and avoid_contact.
05/03/2021 A new version of the survey (V10b) was launched on 04/26/2021. V10b remains the same configuration as V10 and only differs in the backend survey response collection process . Due to a data processing issue in our pipelines, we have found a bug that causes survey responses for this version(V10b) to not be included in the microdata and aggregations provided by the API. Microdata files and aggregates from 4/27/2021 to 5/1/2021 were affected. As of 5/3/2021, we have implemented a hotfix and backfilled the data to include these missing responses. Re-downloading the data will correct any issues with missing responses.
04/29/2021 We have implemented an updated for aggregate indicators in the UMD Open Data API. They are pay_test, reduce_spending, symp_chills, symp_sleep_changes, testing_rate, tested_positive_14d, tested_positive_recent, symp_fever, symp_cough, symp_diff_breathing, symp_fatigue, symp_stuffy_nose, symp_aches, symp_sore_throat, symp_chest_pain, symp_nausea, symp_eye_pain, symp_headache, sick_spend_time_7d ,and ever_tested.
04/29/2021 Recent Update for issue with standard errors and informed_access:
Issue #1: Non-CLI/ILI standard errors
Overview
Weighted and unweighted standard errors were switched in our API for the Global COVID-19 Symptom Survey. While implementing the fix, we aligned the weighted standard error definition with that used in the contingency table aggregates and for CLI/ILI. This definition is as follows, where x bar is the weighted mean: std_equation
Scope
This issue affects standard errors previously reported in our aggregate data API for all indicators except CLI and ILI. It affects both daily and smoothed estimates, even though only weighted estimates are reported for smoothed (i.e., the SEs previously reported for smoothed weighted estimates were unweighted).
This issue does not affect individual-level survey responses that are provided to entities who have signed a microdata use agreement. It also does not affect the US data which has been collected and distributed by Carnegie Mellon University.
Mitigation
As of April 29, we have released an update to our API that fixes the issue for both historic and future data. Users who have downloaded historic data will need to re-download the data to ensure that they have up-to-date estimates.

Issue #2: informed_access indicator
Overview
The definition for the informed_access indicator was implemented incorrectly. The definition has been revised and now reflects the percentage of respondents who reported being very informed or moderately informed about how to be able to get a COVID-19 vaccine.
Scope
This issue affects previously released daily and smoothed estimates for the informed_access indicator for all dates on which the indicator was available (from 2021-03-01 onward).
This issue does not affect individual-level survey responses that are provided to entities who have signed a microdata use agreement. It also does not affect the US data which has been collected and distributed by Carnegie Mellon University.
Mitigation
As of April 29, we have released an update to our API that fixes the issue for both historic and future data. Users who have downloaded historic data will need to re-download the data to ensure that they have up-to-date estimates.
03/09/2021 We have changed the naming for all the hes and hesitant indicators, except for the hesitant_sideeffects indicator. We have replaced hes and hesitant with barrier_reason. This change was implemented to better describe what the indicators represent.
03/05/2021 New aggregate indicators for survey version 10 are available now. These include indicators for barrier reasons for why respondents don’t think they need a COVID-19 vaccine, how informed respondents are about the COVID-19 vaccine, and indicators on vaccine appointment information. Please refer to the survey instrument documentation for more information on the questions used for these indicators.
02/06/2021 New aggregate indicators for survey version 9 are available now. These include indicators for barrier reasons for vaccine acceptance from V5 question in survey version 9. The trust_healthcare indicator will be discontinued as of 2/14/2021. As of 2/6/2021, the trust_doctors indicator is being be populated. Question V4_2, which was used for the trust_healthcare indicator, has been discontinued in survey version 9. Question V4_6 replaces question V4_2 in survey version 9. Question V4_6 is used in the trust_doctors indicator. Please refer to the survey documentation for more information on the question differences.
01/21/2021 We have implemented an updated definition for some of the aggregate indicators in the UMD Open Data API. This definition change impacts the following indicators: mask-wearing, financial worry, social distancing, and vaccine acceptance. We are implementing this change to make our estimates more directly comparable to those in Carnegie Mellon University Delphi research group’s COVIDcast API, which uses data from the US version of the COVID-19 Symptom Survey. Find a more detailed description under the release log section here.
12/06/2020 We released an update to our API. Before this update, the definition of COVID-like illness(CLI) and influenza-like illness (ILI) had been inadvertently switched in the API data. We have implemented a fix that corrects both historic and future data. This issue does not affect individual-level survey responses that are provided to entities who have signed a microdata use agreement. It also does not affect the US data which has been collected and distributed by Carnegie Mellon University. US estimates in the UMD and Facebook maps are also unaffected. Click here to read a detailed summary of the issue and fix.