Edited language regarding weekly deaths (#1545)

Author: tinatownes

docs/api/covidcast-signals/nchs-mortality.md

@@ -30,8 +30,8 @@ as additional death certificates from recent weeks are received and tabulated.
 | `deaths_covid_incidence_prop` | Number of weekly new deaths with confirmed or presumed COVID-19, per 100,000 population <br/> **Earliest date available:** Epiweek 05 2020 |
 | `deaths_allcause_incidence_num` | Number of weekly new deaths from all causes <br/> **Earliest date available:** Epiweek 05 2020 |
 | `deaths_allcause_incidence_prop` | Number of weekly new deaths from all causes, per 100,000 population <br/> **Earliest date available:** Epiweek 05 2020 |
-| `deaths_flu_incidence_num` | Number of weekly new deaths involving Influenza and at least one of (Pneumonia, COVID-19) <br/> **Earliest date available:** Epiweek 05 2020 |
-| `deaths_flu_incidence_prop` | Number of weekly new deaths involving Influenza and at least one of (Pneumonia, COVID-19), per 100,000 population <br/> **Earliest date available:** Epiweek 05 2020 |
+| `deaths_flu_incidence_num` | Number of weekly new deaths involving influenza, including those with COVID-19 or pneumonia also listed as a cause of death <br/> **Earliest date available:** Epiweek 05 2020 |
+| `deaths_flu_incidence_prop` | Number of weekly new deaths involving influenza, including those with COVID-19 or pneumonia also listed as a cause of death, per 100,000 population <br/> **Earliest date available:** Epiweek 05 2020 |
 | `deaths_pneumonia_notflu_incidence_num` | Number of weekly new deaths involving Pneumonia, excluding Influenza deaths <br/> **Earliest date available:** Epiweek 05 2020 |
 | `deaths_pneumonia_notflu_incidence_prop` | Number of weekly new deaths involving Pneumonia, excluding Influenza deaths, per 100,000 population <br/> **Earliest date available:** Epiweek 05 2020 |
 | `deaths_covid_and_pneumonia_notflu_incidence_num`| Number of weekly new deaths involving COVID-19 and Pneumonia, excluding Influenza <br/> **Earliest date available:** Epiweek 05 2020 |