COVID-19 Alaska Weekly Case Update: Aug. 16 - 22, 2020

 

This data summary covers COVID-19 in Alaska from Sunday, August 16th through Saturday, August 22nd, 2020.

 

Background

The Alaska COVID-19 Weekly Case Update will be composed every weekend with data from the previous week and the report will be published by the following Wednesday. Data are continually updated on the AK DHSS Data Hub, which reflects the most current case counts. This summary presents data from the previous week and is a snapshot of the information available on known cases at the time. 

 

Highlights

• There are far more active cases in Alaska now than there were at any point in March, April, May or June, but there has been a gradual decrease since a high in late July.
• In the last week, Alaska saw a 11% increase in cases, with 47% of new cases identified in Anchorage. 
• Nearly 40% of this week's new cases were among people aged 20-39 years.
• The percent of Alaskans who have recovered from COVID-19 compared to total cases in Alaska residents is increasing, but there are still more active than recovered cases reported.
• Of complete investigations, 61% of this week's new cases were community-acquired or secondary, meaning that those Alaskans got COVID-19 from others in their community rather than through travel.
• Many people diagnosed with COVID-19 statewide continue to report attending social gatherings, community events, church services and other social venues while they were contagious but before they were aware they had the virus. 
• Hospital beds used for patients with COVID-19 ranged from 32 to 45 over the past week.
• Total statewide hospital bed occupancy has remained between 50% to 60% over the past week, although this includes urban hospital beds as well as beds in smaller hospitals that do not often accept transfers from other hospitals.
• Alaskans should avoid gatherings, wear masks in public, keep six feet of distance from anyone outside of their household and wash hands frequently to slow the spread of COVID-19.  

New cases

This week saw 482 new cases in Alaskans and 15 in nonresidents, for a total of 4,741 and 817 respectively. Several cases previously classified as resident cases have since been reclassified as nonresident cases after further investigation took place. 12 additional Alaskans required hospitalization this week for COVID-19, for a total of 197 since the epidemic began; several hospitalizations that began before this week were also identified. Four additional deaths were reported this week, for a total of 32. By convention, deaths are counted based on the residency of the patient rather than where they contracted the virus.  

 

Epidemic curve

This analysis projects growth or reduction in cases predicted in the coming weeks based on the growth of cases in recent weeks. The most recent 7 days (grey bars) are not included because there can be a delay in reporting data. This model assumes exponential growth or reduction in cases and can be a useful tool to visualize how quickly cases are increasing or decreasing. This curve does not project what might happen if more people start wearing masks or increase physical distancing; it assumes Alaskans and visitors to Alaska do not change their behavior. The dotted line is the average prediction, and the grey shaded area is estimated error for the predicted rise in cases. For a full description of methods, visit https://coronavirus-response-alaska-dhss.hub.arcgis.com/

Currently, cases are predicted to halve about every 90 days based on the current case trend, worse from from last week, when cases were predicted to halve every 20 days. Keeping the case trend prediction downsloping will depend on a continued effort among Alaskans to slow the spread of transmission through physical distancing, masks and limiting contacts. 

 

Communities affected this week 

New cases were found in Alaskans who are residents of the following communities:

·         Anchorage (226), Chugiak (2), Girdwood (1) and Eagle River (11), for a total of 240 new cases in the Anchorage Municipality. 

·         Fairbanks (63), North Pole (7) and one in a smaller community for a total of 71 new cases in the Fairbanks North Star Borough

·     Wasilla (41), Palmer (11), Willow (1), Houston (1) and Big Lake (3) for a total of 57 new cases in the Matanuska-Susitna Borough

·     Kenai (18), Soldotna (14), Homer (2), Kenai (10) and a smaller community (2) for a total of 46 new cases in the Kenai Peninsula Borough

·     Valdez (1) and 6 in a smaller community or communities in Valdez-Cordova Census Area, for a total of 7

·     Yukon-Koyukuk Census Area (9)

·     Juneau (15) and Douglas (2), for a total of 17 in the Juneau City and Borough

·     Ketchikan (3)

·     Kotzebue (13) and 4 in a smaller community or communities in the Northwest Arctic Borough, for a total of 17

·     Sitka (3)

·     Kodiak (3)

·     Utqiagvik (6) and one in a smaller community in the North Slope Borough, for a total of 7

·     Nome (5) and 4 in a smaller community or communities in the Nome Census Area for a total of 9

·     Bristol Bay plus Lake and Peninsula (1)

·     Dillingham (1)

·     Bethel (4) and 5 in a smaller community, for 9 total in the Bethel Census Area 

·     Prince of Wales-Hyder Census Area (5)

·     Wrangell (1)

 

Case rates and alert levels

The 7 day case rate map depicts cases adjusted by population for a given region (cases per 100,000 people). The regions are large because Alaska is a large state with few densely populated centers, so this case rate can only be meaningful across large regions. 

The highest case rate this week was in the Northwest Region, which nearly doubled from 8.3 to 15.6. Next is Anchorage Municipality, which improved from 14.6 to 11.7 in the last week, and Fairbanks North Star Borough, at 10.3 from 7.3. The Interior Region improved to 9.8 from 11.0, while Kenai Peninsula Borough improved from 10.0 to 8.8. Mat-Su increased from 5.8 to 7.7 this week, while Juneau City and Borough improved from 16.5 to 6.7. The southern Southeast region improved from 7.2 to 5.7, while the Y-K Delta improved from 6.0 to 4.9. The Southwest Region and the northern Southeast region had few cases this week and a rate was not calculated. Most states use a 7 day case rate per 100,000 population to estimate trends in community transmission. Roughly, rates of >10 cases daily per 100,000 population correspond to widespread community transmission and >5 to moderate community transmission, but a sharp increase or decrease in these rates can help predict how the next week or weeks will look for the region. 

7-day Case Rate Map (cases per 100,000 people)

 

Because of Alaska’s unique geography and smaller population, a 14 day case rate can also be useful. The alert level map below, designed to help long term facilities decide when it may be safer to allow visitors in their facilities, uses a 14 day case rate approach. 

In high alert level (red) is the Northwest Borough (11.7 from 7.8 last week), the Interior Region excluding Fairbanks (10.4 from 8.5), Juneau City and Borough (11.6 from 13.0), and the Anchorage Municipality (13.0 from 14.4). 

In intermediate alert level (orange) is Fairbanks North Star Borough (8.3 from 6.0), Kenai Peninsula Borough (9.1 from 7.3). Matanuska-Susitna Borough (6.4 from 5.1), the Y-K Delta Region (5.4 from 3.8), and the Southern Southeast region (6.5 from 4.3). 

In low alert level (yellow) is the Northern Southeast Region (4.5, the same as last week) and the Southwest region (3.5 from 3.7). 

More information on alert levels is available on this page. 

 

How Alaskans acquired COVID-19

DHSS monitors how people most likely got the virus. In green in the plot below are Alaska residents who acquired COVID-19 by traveling to other states or countries. In March, a substantial proportion of our cases were related to Alaskans returning from elsewhere, while in April and May, fewer Alaskans traveled. Since June, as travel has started to increase, cases in Alaskans related to travel have begun to occur more regularly. 

In blue below are cases where Alaskans got COVID-19 from a known contact. These are people who did not leave the state, but we could trace their illness back to the person they got it from. The goal is for contact tracing to identify each of these cases where someone got it from someone else they had contact with so they can let all other contacts of both people know to quarantine. As contact tracing expanded in May, more cases from contacts were identified.

In red, however, are cases where Alaskans got COVID-19 and contact tracing was not able to establish a clear source. This demonstrates that there are other cases in our communities that we have not found yet. The biggest increase in cases in Alaska has been in people aged 20-39, with many cases linked to bars and social gatherings.

Grey bars show the cases where the investigation has not yet concluded. Since the workload for contact tracers has more than doubled in the last few weeks, they are working as fast as possible to identify and quarantine contacts. Alaskans can help contact tracers move faster and prevent more cases by keeping their contact list small, keeping a diary of who they are in close contact with (defined as within 6 feet for 10 minutes or more), wearing cloth face coverings when around any non-household members or in public, and responding promptly to being contacted. 

 

 

Age and gender distributions

More COVID-19 cases have been found in adults aged 20-39 than any other age group. Gender distribution has been close to equal, with slightly fewer than half of cases in males and slightly over half in females. 

 

 

Distribution of cases compared to population distribution

Includes data from all cases reporting one or more races. 

Based on these data, American Indian and Alaska Native as well as Native Hawaiian and Pacific Islander populations are disproportionately affected. 

Race	Number of cases	Percent of cases (of those for whom a race is known)	Percent of Alaska population
American Indian and Alaska Native	668	27%	16%
Native Hawaiian and Pacific Islanders	188	7.5%	1%
Black/African American	156	6.2%	4%
Asian	114	4.5%	7%
Multiple	143	5.7%	8%
White	1120	45%	65%
Other race	126	5.0%
Total for whom a race is known	2515
Under investigation	1780
Race unknown	293

 

Hospital capacity

Hospitals report all inpatient beds in this total, including those for infants and obstetrics. However, the ICU bed count includes only staffed adult and pediatric ICU beds, as NICU (neonatal ICU) beds can only be used for infants and would not be useful for teenage or adult patients with severe COVID-19.

Hospitals remain below capacity, with ventilators and ICU beds available, but use continues to slowly rise. 197 Alaskans have required hospitalization for COVID-19. Bed occupancy due to COVID-19 rose in July, following a rise in cases, and has not yet significantly decreased.

 

 

Risk of severe COVID-19 by race and ethnicity

CDC notes that older adults and people with underlying medical conditions are at increased risk for severe illness if they get COVID-19. In particular, CDC specifies cancer, chronic renal disease, COPD, immunocompromised state from a solid organ transplant, obesity (BMI 30 or higher), serious heart conditions such as heart failure, coronary artery disease and problems with the heart muscle, sickle cell disease and type 2 diabetes as carrying an increased risk of severe illness. 

Data was immediately available for the prevalence of several of these conditions among Alaskans. Because Alaska’s population is small and the data collected is even smaller, several of these estimates are considered statistically unstable, or not very reliable. However, they are presented here as an example of how different chronic diseases impact different populations of Alaskans, and they may be able to predict increased risk of severe COVID-19 among some populations.

 

Race or ethnicity	Cardiovascular disease	COPD	Diabetes	Obesity	Current smoker
Multiple races, non-Latino	3.3%*	2.4%*	7.2%	28.6%	12.9%
Hispanic or Latino	5.2%*	5%*	10%	23.1%	25.5%
White	4.2%	5%	8.3%	30.6%	15.9%
Native Hawaiian or Other Pacific Islander	No data available	No data available	6.6%*	55.4%	17.9%
Black or African American	8%*	6.1%*	17.2%	44.3%	20%
Asian	No data available	2.9%*	8.6%	18.7%	8.5%
Alaska Native	4.6%	7.4%	7.8%	36.3%	36.8%

 

*Statistically unstable: there is not enough data for this category to consider this a reliable estimate

 

Hospitalizations and deaths by race and ethnicity

Hospitalization percentages are influenced both by the number of people of that race hospitalized and the number of people of that race who have been found to have COVID-19. This means that a population that either has a high degree of severity of COVID-19 and/or a low rate of testing and many undiscovered cases may have a high percent hospitalized shown in state data. Conversely, a population that has many hospitalizations but has a disproportionately high testing rate may have a lower percent hospitalized relative to other groups, since they have fewer undetected cases.

 

Because Alaska has had 32 deaths related to COVID-19, it is very difficult to draw robust conclusions from these small numbers. Hospitalizations may be a better indicator of actual severity among different populations, since those draw from larger numbers. Other states have had far larger numbers of hospitalizations and deaths and can draw conclusions about trends with more confidence. 

 

Disparities in severity among Alaskan populations have begun to trend towards mirroring those in other states. However, state and federal data reflects significant racial disparities in the impact of COVID-19 on minority communities, and Alaskan populations such as Alaskan Native People and Pacific Islanders are known to experience conditions that place them at higher risk for severe COVID-19 at increased rates compared to other groups. Racial disparities in these numbers may be best interpreted as proxies for differences in contributing factors such as rates of medical comorbidities, exposure risks, and ready access to medical care. Care should be taken not to interpret racial disparities as inherent biological differences among races.

 

Race	Number of cases	Percent of cases who were/are hospitalized	Percent of cases who have died
Native Hawaiian and Pacific Islander	188	17.6%	2.1%
Asian	114	10.5%	1.8%
American Indian and Alaska Native	668	6.8%	1.5%
Black/African American	156	3.8%	0%
Multiple races	143	1.4%	0%
White	1120	5.6%	1.3%
Other	126	4.8%	0%
Unknown or not yet identified	1,780	0.9%	0%
All cases for which a race is known	2,515	7.3%	1.3%
All cases	3706	4.1%	0.7%

 

Reporting of deaths due to COVID-19

Although several of these deaths occurred in Alaskans who acquired the disease in another state and never traveled to Alaska during their illness, they are counted as deaths in our reporting by national convention. In accordance with national standards, case counts for Alaska reflect known cases in all Alaska residents, regardless of where they acquired the infection or where it was discovered. This provides consistency and avoids cases and deaths being double-counted between states. Cases found in Alaska that are not among Alaska residents are reported under nonresident cases. 

32 Alaskans are reported as having died from COVID-19. 

 

Recovered cases

Reporting of recovered cases varies because reporting typically lags a few days. This week, 322 more Alaskans were reported to have recovered (either they have been confirmed by public health as recovered or they have completed 10 days of isolation) from COVID-19, for a total of 1,559, or 32% of total cases. This is an increase of 3% from last week, meaning that the general trend is towards more Alaskans recovering from COVID-19 than are newly testing positive. Encouragingly, between the close of data reporting for this summary and its publication, many more recovered cases were reported. As of August 26, recovered cases in Alaskans stands at 1,899, or 39% of total cases in Alaska residents.