COVID-19 Alaska Weekly Case Update: Aug. 30 - Sept. 5 2020

COVID-19 Weekly Case Update

This data summary covers COVID-19 in Alaska from Sunday, August 30th through Saturday, September 5th, 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 Alaska Coronavirus Response 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. 

 

Note: Our apologies for the delay with this week's weekly case update. We typically publish by Wednesday evening. 

 

Highlights

  • We continue to see new cases of COVID-19 in Alaska
  • The largest increases in cases continue to be in Alaskans aged 20-29
  • 14-day case rates are high and rising in Fairbanks North Start Borough and Anchorage Municipality
  • The majority of new infections among Alaskans are from community spread, not from travel. Most Alaskans get the virus from someone they work, socialize, or go to school with.
  • Many cases do not have a clear source, meaning that contact tracers have not able to identify where the person got the virus. This could mean that there are cases in our communities that we do not know about. 
  • The predicted epidemic curve is still downtrending, but not as quickly as last week
  • New nonresident cases are downtrending, which may be in part related to more nonresidents being tested for COVID-19 prior to travel to Alaska
  • Many Alaskans who are diagnosed with COVID-19 report that they went to social gatherings, community events, church services and other social venues while they were contagious but before they knew they had the virus
  • Cases disproportionately affect Alaska Native People and that proportion is rising; Alaskans who identify as Black or Pacific Islander are also disproportionately impacted although the numbers of people affected in these populations are smaller, making it more difficult to judge whether these differences will be statistically significant
  • Hospital occupancy statewide remains steady
  •  Anyone with even one new symptom of COVID-19 (fever, chills, cough, shortness of breath, difficulty breathing, fatigue, muscle aches, body aches, headache, new loss of taste or smell, sore throat, congestion, runny nose, nausea, vomiting, or diarrhea), even if it is very mild, should get tested for COVID-19 right away. Tests are most accurate in the first few days of symptoms, and if the test is positive, getting tested right away helps contact tracers move as quickly as possible. 
  •  Alaskans can help contact tracers work to slow the spread of COVID-19 by answering the phone promptly if contacted and providing accurate information.
  • Alaskans should avoid gatherings, wear masks when around any non-household member, keep six feet of distance from anyone not in their household and wash hands frequently to slow community transmission of COVID-19.

 

New and recovered cases

This week saw 541 new cases in Alaskans and 21 in nonresidents, for a total of 5,765 and 891 respectively. Several cases previously classified as resident cases have since been reclassified as nonresident cases after further investigation took place. 17 additional Alaskans required hospitalization this week for COVID-19, for a total of 232 since the epidemic began. Five additional deaths were reported this week, for a total of 42. By convention, deaths are counted based on the residency of the patient rather than where they contracted the virus.   

 

82 Alaskans are presumed to have recovered (either they have been confirmed by public health as recovered or they have completed 10 days of isolation) from COVID-19 this week, for a total of 2,121, or 37% of total cases.  

 

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 210 days based on the current case trend, which is worse than the case trend of last week when cases were predicted to halve every 75 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 (302), Girdwood (2), Eagle River (7), for a total of 311 in the Anchorage Municipality
  • Bethel (1) and smaller communities in the Bethel Census Area (7) for a total of 8
  • Fairbanks (89) and North Pole (21) for a total of 110 in the Fairbanks North Star Borough
  • Juneau (18) and Douglas (1) for 19 in the Juneau City and Borough
  • Kenai (8), Soldotna (5) and one in a smaller community, for a total of 14 in the Kenai Peninsula Borough
  • Ketchikan (1)
  • Wasilla (14), Palmer (18), Big Lake (3) and 1 in Houston for 36 in the Mat-Su Borough
  • Nome Census Area (6)
  • Utquiagvik (12) 
  • Kotzebue (2) and 2 in a smaller community or communities, for a total of 4 in the Northwest Arctic Borough
  • 2 in a community or communities in the Prince of Wales-Hyder Census Area
  • Valdez (1), and one in a smaller community, for a total of 2 in the Valdez-Cordova Census Area
  • Bristol Bay plus Lake and Peninsula Census Areas (5)
  • Southeast Fairbanks Census Area (1)
  • Prince of Wales-Hyder Census Area (2)
  • Denali Borough (1)
  • Kodiak (4)
  • Wrangell (1)
  • Yakutat plus Hoonah-Angoon Census Areas (3)
  • Yukon-Koyukuk Census Area (1)

 

Case rates and alert levels

Average Daily Case Rate in Last 7 Days (cases per 100,000 people)

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 regions designated here are regions used as behavioral health regions and attempt to observe similar characteristics across a region by not combining highly isolated areas with urban areas whenever possible. 

 

Regions with increased rates this week included the Anchorage Municipality (15 from 13), Fairbanks North Star Borough (16 from 11.5), the Northwest region (11.5 from 10.4), Kenai Peninsula Borough (3.2 from 2.7), the Southwest region (4.5 from a rate too small to calculate last week) and Juneau City and Borough (8.5 from 4.0).

 

Among improved regions are the Interior Region, with a rate too small to calculate this week from 5.5 last week, Mat-Su (4.8 from 5.0), the Southern Southeast Region (too small to calculate from 6.5), Y-K Delta Region (4.3 from 10.9) and the Northern Southeast Region (a rate too small to calculate from 9.1 last week). 

 

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.  

 

14 -Day Alert Levels (average daily 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 above uses a 14 day case rate approach. 

 

In high alert level (red) is the Northwest Borough (11 from 12.7),  Fairbanks North Star Borough (13.7 from 10.8), and the Anchorage Municipality (14.1 from 12.6). 

 

In intermediate alert level (orange) is Juneau City and Borough (6.3 from 5.1), the Y-K Delta Region (7.6 from 7.3), the Northern Southeast Region (5.2 from 6.3), 

 

In low alert level (yellow) is the Southwest region (2.3 from 1.7),  Kenai Peninsula Borough (2.9 from 5.8), Matanuska-Susitna Borough (4.9 from 6.2), the Interior Region excluding Fairbanks (4.3 from 7.9), and the Southern Southeast region (5.2 from 6.1). 

 

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. However, travel-related cases are now a minority compared to community-acquired cases. 

 

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. 

 

Grey bars show the cases where the investigation has not yet concluded. 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 more than half of cases in males and slightly fewer than 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

951

30% 

16%

Asian 

136

4.3% 

7%

Black/African American

190

6.0% 

4%

Multiple

186

5.9% 

8%

Native Hawaiian and Pacific Islanders

227

7.2% 

1%

White

1,299

41% 

65%

Other race

165

5.2% 

 

Total for whom a race is known

3,154

 

 

Under investigation

2,264

 

 

Race unknown

357

 

 

 


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. 232 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.

 


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 42 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

In cases of that race, percent who were/are hospitalized

In cases of that race, percent who have died

American Indian and Alaska Native

941

6.5% 

1.5% 

Asian

136

8.8% 

2.2% 

Black/African American

190

3.7% 

0%

Multiple races

186

1.6%

0%

Native Hawaiian and Pacific Islander

237

19% 

2.2% 

White

1,299

5.4%

1.4%

Other

165

4.2% 

0%

Unknown or not yet identified

2,621

2.5% 

0.3%

All cases for which a race is known

3,154

7.0%

1.3%

All cases

5,765

4.4% 

0.7%

  

 

Nonresident cases

Of the 21 nonresident cases identified this week, 6 were in the Aleutians East Borough, 6 were in the Anchorage Municipality, 1 was in the Bethel Census Area, 2 were in the Fairbanks North Star Borough, 1 was in Juneau City and Borough, 1 was in the Kenai Peninsula Borough, 2 were in Ketchikan Gateway borough, and one was in the Kodiak Island Borough. One nonresident case did not yet have the location identified. 

 

6 nonresident cases were associated with tourism or visiting purposes and 6 with other industries. 

 

Test positivity rate

The test positivity rate is the percentage of tests performed in a given area that come back positive. While the positivity rate is not a standalone measure of the amount of viral transmission in a region, it helps visualize whether the testing being conducted is sufficient to meet the need to detect viral transmission in that region. Lower test positivity rates are better, since they reflect more tests being performed to find each positive case. Positivity rates over 5% are concerning because they may indicate that testing is insufficient or that there is significant ongoing viral transmission.

 

In the map below, there are several smaller boroughs or census areas where the positivity rate as currently reported is >10%. This may reflect several different scenarios, including that those boroughs or census areas have tested primarily people who were likely to have the virus this week (for example, they tested only people who had symptoms or known exposures), that they have reported any positive results faster than they have reported any negative results (since there can be a lag in reporting, but positive results are often communicated immediately when they are received), or that they have tested widely and have had a significant uptick in cases in the last week. Several of the boroughs or census areas in red below had just a single positive test in the last week, but few negative tests have been reported from that borough or census area as of yet; for example, one borough has a 50% positivity rate for the last week with just one positive and one negative test yet reported. The overall state positivity rate this week was 2.0%, similar to last week’s rate of 1.9%. 

 

Alaska’s overall positivity rate, of 387,057 tests total, has remained between 1.5% and 3% in recent months and has not exceeded 4% during the pandemic so far. Testing turnaround time averaged 3.1 days in the last two weeks at the state lab, 3.9 days at facilities and 3.2 days for commercial labs for all tests reported in Alaska. 

 

 

 

Tourism, visitors and airport testing

Airports report data on a Saturday through Friday cycle, meaning that the airport screening numbers in this section reflect data collected on Saturday, August 29th through Friday, September 4th. 

 

Travel data was significantly impacted by delays in reporting this week. Several airports had not yet reported complete data at the time of this publication. One airport found that several travelers had completed more than one travel declaration form. For that reason, these numbers should be interpreted as preliminary estimates only. 

 

This week saw 19,518 travelers screened at airports entering Alaska, and 2,549 (13%) were tested on entry. 1,044 Alaskans selected a 14 day quarantine (5% of total travelers). 12,672 provided proof of another test performed within 72 hours of landing in Alaska (65%). The remaining 3,253 (17%) provided proof of having recovered from COVID-19, were essential workers following a community and workplace protection plan or were Alaskans who had been gone for fewer than 24 hours. 15 positive results from the tests performed at the airport have been reported so far, for a test positivity rate of 0.5%, however several airports have not yet reported positive tests for the week. 

 

Since testing began thirteen weeks ago, 253,623 travelers have been screened at Alaska airports. 127,519 (50%) tested prior to travel, 70,658 (28%) have tested in Alaska airports, and 27,289 (11%) selected a 14 day quarantine. There have been 395 positive tests through airport testing, for an overall test positivity rate of 0.6%.

 

Of the 21 cases in nonresidents this week, six were linked with visiting or tourism. 3 were in the Aleutians East Borough, one was in the Anchorage Municipality, one was in Fairbanks North Start Borough and one was in Juneau City and Borough. 

 

Seafood industry

Of 21 nonresident cases total identified this week, none are workers in the seafood industry. 

 

Data timeliness and accuracy

Weekly summaries are published early the following week because that gives the state public health workforce time to collect data, verify accuracy, make sure cases have not been counted in multiple places and verify patient identities. This summary is designed to review a week’s data from the Alaska Coronavirus Response Hub dashboard, which displays same-day or next-day data. The dashboard data occasionally changes as new information is received or as cases are reclassified once verification takes place, since this process takes time. Weekly summaries reflect our most current and complete knowledge about cases in the previous week. 

 

Further information