---
id: "epi_week"
kind: "datatype"
status: "draft"
is_pii: false
categories: ["datetime", "medical"]
langs: ["common"]
quality: 80
url: "https://registry.apicrafter.io/datatype/epi_week"
---

# Epidemiological week (CDC MMWR week) (`epi_week`)

> **Draft.** Draft records have not been reviewed yet and may be incomplete or wrong; do not treat them as authoritative for legal or compliance decisions.

Week number used by the US Centers for Disease Control and Prevention (CDC) to report notifiable diseases in the Morbidity and Mortality Weekly Report (MMWR). MMWR weeks start on Sunday. Week 1 is the first week of the year with at least four days in that calendar year, so the last days of December can fall in week 1 of the next year. Values run from 1 to 53. Some data sets combine year and week as YYYYWW (202101); that form looks like a year and month, so it is not covered by the regexp.

- Parent datatype: `week_of_year`
- Personal data (PII): no
- Categories: Date and time (datetime), Medical/pharma identifiers (medical)
- Countries: global
- Languages: Common to most languages (common)
- Classification: categorical

## Detection

Regular expression (Python `re`):

```
^(?:0?[1-9]|[1-4]\d|5[0-3])$
```

## Examples

- `1` — first MMWR week
- `52` — last week of a 52-week MMWR year
- `54` (invalid example) — out of range

## Translations

- es: Semana epidemiológica
- ru: Эпидемиологическая неделя (MMWR)

## Sources

- doc: <https://ndc.services.cdc.gov/wp-content/uploads/MMWR_Week_overview.pdf>
- other: <https://cmu-delphi.github.io/delphi-epidata/api/date_formats.html>

## Quality

Score 80/100. Missing: mapping (Wikidata, Schema.org, ...), detector coverage.

JSON: <https://registry.apicrafter.io/api/v1/datatypes/epi_week.json> · Edit: <https://github.com/apicrafter/metacrafter-registry/edit/main/data/datatypes/any/datetime/epi_week.yaml>