NEVADA HEAT-RELATED ILLNESS REPORT: MAY 01 to SEPTEMBER 22, 2024
The Office of State Epidemiology (OSE) within the Nevada Division of Public and Behavioral Health (DPBH) monitors heat-related illnesses in Nevada from May to September.
Heat-related illnesses occur when the body cannot cool down effectively. This can lead to mild issues such as heat cramps or severe, potentially deadly conditions like heat stroke. Nevada’s dry climate features extreme temperature swings, with summer temperatures often exceeding 100°F, particularly in the southern part of the state. This makes people in Nevada highly susceptible to heat-related illnesses. By using data from these reports, OSE and its partners can improve heat-health alerts and action plans, helping to protect Nevada communities from extreme heat.
Heat-related illnesses and deaths are preventable.
For additional information and resources on heat-related illness, please visit the OSE Heat-Related Illness Webpage.
For additional heat-related illness data, please visit the OSE Heat-Related Illness Dashboard (not yet published).
For a forecasted risk of heat-related impacts, please visit the National Weather Service HeatRisk webpage.
HEAT-RELATED ILLNESS INCIDENCE DATA
Figure 1 shows the daily number of emergency room visits in Nevada from May 01, 2024, to September 22, 2024. It shows visits among Nevada residents and non-residents, detailing the average maximum and average minimum temperatures recorded statewide each day. Table 1 highlights important statewide data points during this period.
| Table 1. Heat-Related Illness Emergency Department Visits in Nevada, 2024, Data Highlights | |||
| Data Characteristic | Data Value | Description | Significance |
|---|---|---|---|
| Total Visits | 3750 | Total number of emergency visits due to heat-related illnesses since May 1, 2024. | Even though not all instances of heat-related illness result in emergency visits, this number provides a gauge of the overall burden of heat-related illness in Nevada during this timeframe. |
| Highest Daily Visits | 99 visits (July 11) | Highest number of emergency visits recorded on a single day since May 1, 2024, including both Nevada residents and non-residents. | Highlights the day with the most significant health burden due to heat. |
| Average Daily Visits | 12.93 | Average number of emergency visits per day since May 1, 2024. | Comparing this number to the Highest Daily Visits number above gives a sense of whether most days had a high number of visits or whether most days had substantially fewer visits than the days with the highest number of visits. If the number of daily visits is similar to the highest number of visits, it indicates that most days had a high number of visits. If the average number of visits is much lower than the highest number of visits, it indicates that most days had a lower number of visits. |
| Proportion of NV Residents | 86.05% | Proportion of total visits made by Nevada residents since May 1, 2024. | A high proportion (86.05%) of Nevada residents means that most of the people who sought emergency care for heat-related illnesses are from Nevada as opposed to out of state residents. |
| Highest Maximum Temperature | 120°F (July 07) | Highest observed maximum temperature recorded statewide since May 1, 2024. | Shows the peak heat intensity during the period and the specific date it occurred. |
| Highest Minimum Temperature | 94°F (July 10) | Highest observed minimum temperature recorded statewide since May 1, 2024. | Shows the highest low temperature recorded and the specific date it occurred, indicating potential minimal overnight cooling. |
Figure 2 shows the number of emergency department visits from May 1 to September 30 for the years 2020 to 2024. This includes visits from both Nevada residents and non-residents. The data is presented using a 7-day moving average, which smooths out daily fluctuations by averaging the number of visits over a rolling seven-day period. Table 2 provides key data points for these years.
| Table 2. Heat-Related Illness Emergency Department Visits in Nevada, 2020–2024, Data Highlights | |||
| Data Characteristic | Data Value | Description | Significance |
|---|---|---|---|
| Multiplier of Average Daily Visits 2024 vs 2020–2023 | 1.65x | The ratio of the average daily visits in 2024 to the average daily visits between 2020–2023 for the same period (up to September 22, 2024). The multiplier (x) indicates how many times greater or smaller the average daily visits in 2024 are compared to the previous four years. | Provides a basic comparison to illustrate how the 2024 heat season so far compares to the previous four years. A value greater than 1.00 indicates more heat-related emergency department visits during the current year than in previous years. |
| Year with Highest Visits | 2024 (3750 visits) | Year with the highest total number of visits from May 1 to September 22. | Indicates the year with the most significant heat-related health burden from May 1 to September 22. |
| Year with Second Highest Visits | 2023 (2705 visits) | Year with the second highest total number of visits from May 1 to September 22. | Indicates the year with the second most significant heat-related health burden from May 1 to September 22. |
| Year with Highest Daily Visits | 2023 (107 visits on July 25) | Highlights the year with the most single-day heat-related emergency department visits. | Highlights the year with the most single-day heat-related emergency department visits. |
| Year with Second Highest Daily Visits | 2023 (99 visits on July 18) | Highlights the year with the second most single-day heat-related emergency department visits. | Highlights the year with the second most single-day heat-related emergency department visits. |
HEAT-RELATED ILLNESS GEOGRAPHIC DATA
Nevada, located in the Mountain West region, is the seventh-largest U.S. state by area. With a population of over three million, more than 73% live in Clark County, which includes Las Vegas, and over 16% reside in Washoe County, which includes Reno. The other 15 counties and equivalents in Nevada make up approximately 11% of the Nevada population.
Figure 3 illustrates the daily emergency department visits in Clark County, Washoe County, and all other Nevada counties combined from May 01, 2024, to September 22, 2024, based on the facility location. For this report, “other counties” refers to Carson City, Churchill, Douglas, Elko, Esmeralda, Eureka, Humboldt, Lander, Lincoln, Lyon, Mineral, Nye, Pershing, Storey, and White Pine counties. Table 3 provides key highlights from these data.
| Table 3. Heat-Related Illness Emergency Department Visits by County, 2024, Data Highlights | |||
| Data Characteristic | Data Value | Description | Significance |
|---|---|---|---|
| Proportion of Visits in Clark County | 89.47% | Proportion of visits in Clark County since May 1, 2024 among both Nevada residents and non-Nevada residents. | Clark County has the largest population in Nevada and also has the largest number of annual visitors. |
| Proportion of Visits in Washoe County | 5.49% | Proportion of visits in Washoe County since May 1, 2024 among both Nevada residents and non-Nevada residents. | Washoe County has the second largest population in Nevada and also has the second-largest number of annual visitors. |
| Proportion of Visits in Other Counties | 5.04% | Proportion of visits in other counties since May 1, 2024 among both both Nevada residents and non-Nevada residents. | These counties have smaller populations and fewer visitors than Clark and Washoe but still face significant risks for heat-related illnesses. They also span rural and frontier regions with limited healthcare facilities, often requiring longer travel distances for care. |
| Highest Maximum Temperature | 120°F (Clark County on July 07) | Highest observed maximum temperature recorded, including the county and date. | Highlights the peak heat intensity recorded and the specific county and date it occurred. |
| Highest Minimum Temperature | 94°F (Clark County on July 10) | Highest observed minimum temperature recorded, including the county and date. | Highlights the highest low temperature recorded and the specific county and date it occurred, potentially indicating minimal overnight cooling. |
Figure 4 presents a map showing the distribution of heat-related illness emergency department visits by county from May 01, 2024, to September 22, 2024 among Nevada residents only. The map uses visit rates per 100,000 population, based on the facility location. Table 4 provides data highlights from the map.
NOTE: Counties in gray do not have emergency departments and therefore do not report emergency department data (Esmeralda, Eureka, Storey).
| Table 4. Heat-Related Illness Emergency Department Visit Rates by County, Nevada Residents Only, 2024, Data Highlights | |||
| Data Characteristic | Data Value | Description | Significance |
|---|---|---|---|
| County with Most Visits | Clark County (2890 visits) | County with the highest number of visits. | Indicates the area with the highest burden of heat-related illnesses. |
| County with Highest Rate | Nye County (129.22 per 100,000) | County with the highest rate of visits per 100,000 population. | Highlights the county with the highest relative burden of heat-related illnesses. |
| Counties without Any Heat-Related Illness Visits | White Pine County, Lincoln County, Pershing County | Counties that did not record any visits. | Highlights the counties where no visits were recorded. |
| Number of Nevada Residents Traveling to a Facility Outside of Their Home County | 84 (2.6%) | Total number and proportion of Nevada residents who sought care in a different county from where they live. | Shows the extent of cross-county travel among Nevada residents seeking emergency care. The county that received the most out-of-county visits from Nevada residents is Clark County. |
HEAT-RELATED ILLNESS DEMOGRAPHIC DATA
Figure 5 shows the distribution of heat-related illness emergency visits by age group, sex, and Nevada residence from May 01, 2024, to September 22, 2024. Table 5 highlights key data points for age and sex.
| Table 5. Heat-Related Illness Emergency Department Visits by Age Group, Sex, and Nevada Residence, 2024, Data Highlights | |||
| Data Characteristic | Data Value | Description | Significance |
|---|---|---|---|
| Sex with Highest Proportion of Visits | Male (65.01%) | Sex with the highest overall proportion of heat-related illness visits among Nevada residents. | Males have an approximate population of 1.6 million in Nevada, which is approximately 50.3% of the state's population. The proportion of visits is higher than the proportion of the population for this group. |
| Age Group with Highest Proportion of Visits | 45-64 (34.20%) | Age group with the highest overall proportion of heat-related illness visits among Nevada residents. | The age category 45-64 years has an approximate population of 800,000 in Nevada, which is approximately 24.9% of the state's population. The proportion of visits is higher than the proportion of the population for this group. |
| Proportion of Visits for Age 0-4 | 0.83% | Proportion of heat-related illness visits for the age group 0-4 years among Nevada residents. | The age group 0-4 years has an approximate population of 200,000 in Nevada, which is approximately 5.4% of the state's population. This age group is known to be at a higher risk for heat-related illnesses. The proportion of visits is lower than the proportion of the population for this group. |
| Proportion of Visits for Age 65+ | 20.67% | Proportion of heat-related illness visits for the age group 65+ years among Nevada residents. | The age group 65+ years has an approximate population of 600,000 in Nevada, which is approximately 17.4% of the state's population. This age group is known to be at a higher risk for heat-related illnesses. The proportion of visits is higher than the proportion of the population for this group. |
Figure 6 shows the distribution of heat-related illness emergency department visits by race and Nevada residence from May 01, 2024, to September 22, 2024. Table 6 provides highlights important data points for race.
| Table 6. Heat-Related Illness Emergency Department Visits by Race and Ethnicity, 2024, Highlights | |||
| Data Characteristic | Data Value | Description | Significance |
|---|---|---|---|
| Race with Highest Proportion of Visits | White (52.07%) | Race with the highest overall proportion of heat-related illness visits among Nevada Residents. | Nevada has an approximate population of 1.5 million White residents, which is approximately 45.4% of the state's population. The proportion of visits is higher than the proportion of the population for this group. |
| Race with Second Highest Proportion of Visits | Black or African American (23.39%) | Race with the second highest overall proportion of heat-related illness visits among Nevada Residents. | Nevada has an approximate population of 300,000 Black or African American residents, which is approximately 9.9% of the state's population. The proportion of visits is higher than the proportion of the population for this group. |
| Ethnicity with Highest Proportion of Visits | Not Hispanic or Latino (81.44%) | Ethnicity with the highest overall proportion of heat-related illness visits among Nevada Residents. | Nevada has an approximate population of 2.2 million Not Hispanic or Latino residents, which is approximately 70.1% of the state's population. The proportion of visits is higher than the proportion of the population for this group. |
ABOUT THIS REPORT
Reporting Period
This report is produced from May 1 to September 30, which is the peak time for heat-related health issues in Nevada. While the primary focus is on the year 2024, data from 2020 to 2024 are also included for comparison.
Data Sources
Emergency department visit data comes from the Electronic Surveillance System for the Early Notification of Community-Based Epidemics (ESSENCE), which tracks emergency department visits based on chief complaints (the primary reason for the visit) and discharge diagnoses (the final medical determination). Currently, 41 emergency departments in Nevada report data to ESSENCE. All counties have at least one reporting facility, except for Esmeralda, Eureka, and Storey counties. These three counties do not have dedicated emergency facilities and instead rely on emergency medical services (EMS), urgent care, and community health nurses for initial emergency care.
Meteorological data is sourced from NOAA Climate Data Online, providing daily temperature records from one weather station per county. Population estimates are derived from the US Census Population Estimate Program (PEP), using population estimates from 2023.
Inclusion Criteria
This report includes data from emergency department visits for heat-related illnesses, based on the facility’s location during the reporting period. The inclusion criteria are detailed in the Heat-Related Illness v2 Definition Factsheet and Technical Brief, which describes the query parameters used in ESSENCE to identify these visits. A patient’s Nevada residency and county of residence were determined from the home address listed in their medical record.
Visits
A “visit” is an instance of evaluation or treatment at a participating emergency department. Multiple visits by the same person are counted separately. For example, a patient receiving treatment three times for heat exposure will contribute three separate visits.
Limitations
This report provides descriptive statistics for heat-related illnesses in Nevada’s emergency departments. It does not analyze causes of heat-related illnesses and these conditions are often underdiagnosed and underreported. The data is preliminary and subject to change. This report should not be used to determine the exact number of emergency department visits in Nevada because not all emergency departments submit data to ESSENCE. Only visits to participating facilities are counted, and many rural and frontier areas lack healthcare facilities. Additionally, this report focuses on the facility’s location rather than the patient’s county of residence, which may not fully capture the geographic distribution of heat-related illness. The inclusion and exclusion criteria used in syndromic surveillance may result in the omission of genuine visits or the unintentional inclusion of unrelated visits. Non-certified meteorological data focuses on maximum and minimum temperatures, potentially missing other influential factors like humidity.
For questions about this report, please contact stateepi@health.nv.gov.