COVID-19 Alaska Weekly Case Update: Sept. 27 – Oct. 3, 2020

Case trends and predictions

  • Alaska saw a sharp acceleration in new cases in the last week. The state had previously seen a steady rise over the preceding six weeks, but this last week saw substantial increases in case rates in nearly every region, with the largest increases in cases in Anchorage and Fairbanks. 
  • The daily state case rate as of October 3 data is 16.3, up from 11.7 on September 26th. This number is cases per 100,000 people averaged over the last 14 days. The state alert level is high. 
  • Compared to other states’ case rates, Alaska’s average case rate per capita over the last 7 days (20.1 average daily cases over the last week per 100,000) has jumped from #24 up to tying for #13 with Tennessee, just below Wyoming (21.6) and worse off than Alabama and Kansas, both at 19.6. between Nevada (13.4) and Indiana (12.7). If Anchorage were its own state, its 7-day case rate (18.4) would put it at rank #6, between Utah and Idaho, and if Fairbanks were a state, its 7-day rate of 33.6 would make it #5 in the nation, just behind Montana. The North Slope Borough would be #4 with a 7-day rate of 34.9, while the Northwest Arctic Borough’s 7-day case rate of 63.7 puts it at a higher average case rate this week than any state average in the US. Nationally, cases have been rising since mid-September, particularly in the Midwest but increases have been seen in most states this week. 24 states currently have 7-day average case rates over 15 per 100,000.
  • The reproductive number, a measure of contagion, is currently estimated to be approximately 1.14, an increase from 1.03 one week ago. A reproductive number of 1 means that each person who is diagnosed with COVID-19 gives it on average to one other person. A reproductive number of more than 1 means that the epidemic is growing, and the goal is to have enough people wear masks, stay at least 6 feet from others, and stay home and get tested when they are sick that Alaska’s reproductive number decreases to well below 1. Our reproductive number was below 1 as recently as late August.
  • An updated model epidemic curve predicts Alaska’s cases will continue to accelerate over the next week. One week ago, cases were now expected to double every 105 days, with a daily projected growth rate of 0.66%. This projection has worsened, with cases now expected to double around every 22 days, with a daily projected growth rate of around 3%.
  • Nonresident cases, which peaked in late July, decreased over August and continue to downtrend.
  • Alaska continues to have the fewest COVID-19 related deaths per capita of any US state, but this week passed Wyoming in total number of deaths. 

Regional trends

  • Anchorage Municipality and Fairbanks North Star Borough both had substantial increases in case rates this week, indicating accelerating cases and high levels of community transmission. Anchorage Municipality’s case rate is now 21.5 from 16.1 last week, while Fairbanks North Star Borough is at 21.2 from 16.3. 
  • Northwest Region increased from 27.9 to 30.7, remaining the highest rate of new cases of any borough reported.
  • The Interior Region and Mat-Su both saw significant case increases this week and moved into the intermediate zone, with case rates increasing to 7.9 and 5.9 respectively.
  • Juneau City and Borough improved to 7.4 from 12.3 the week before and is now in the intermediate zone.
  • The Y-K Delta region improved from 8.7 to 7.1, remaining within the intermediate zone.
  • The Interior Region, Kenai and Northern Southeast Region also saw increases this week but remain in the low transmission zone

Regional case trends

Behavioral Health RegionAverage new cases Aug 16 – 29Average new cases Aug 23- Sept 5Average new cases  Aug 30- Sept 12Average new cases Sept 5- Sept 19Average new cases Sept 12- Sept 26Average new cases Sept 27- Oct 3
Anchorage Municipality12.614.113.513.216.121.5
Fairbanks North Star Borough10.813.717.115.916.321.2
Interior Region except Fairbanks North Star Borough7.94.32.73.14.97.9
Juneau City and Borough5.16.313.416.312.37.37
Kenai Peninsula Borough5.82.92.21.82.53.55
Matanuska-Susitna Region6.24.94.34.74.05.86
Northern Southeast Region6.35.22.13.14.24.89
Northwest Region12.711.010.715.627.930.7
Southern Southeast Region6.15.22.5Insufficient data; low case rateInsufficient data; low case rateInsufficient data; low case rate
Southwest Region1.72.34.23.53.54.7
Yukon-Kuskokwim Delta Region7.37.66.0 8.48.77.1
Statewide7.07.98.710.211.716.3

New cases, hospitalizations and deaths

  • This week saw 924 new cases in Alaskans, a significant jump from last week’s 645 new cases, for a total of 8,405 cumulative cases in Alaskans. While 3,701 of those are recorded as being active, or 44%, and 4,704 Alaskans are thought to have recovered or completed their isolation period, data on recovery lags data on new cases and is not up to date. This should not be interpreted as the number of true active cases decreasing since data entry of recovered cases has increased in recent weeks; true active cases are likely increasing significantly with rising case rates. For that reason, in future weekly case summaries we will not report the number of active or recorded cases, although this information can be obtained at the DHSS Data Hub linked above.
  • Cumulative hospitalizations increased to 300 with 17 new this week.
  • Deaths among Alaska residents increased by 2 to 58 total.
  • There were 21 nonresident cases identified this week, for a total of 971. 

How COVID-19 spreads in Alaska

  • 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 been able to identify where the person got the virus. This means that there are cases in our communities that we do not know about.
  • 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.
  • The distribution of cases among people of different races and ethnicities has not changed significantly since last week.
  • Cases continue to increase most rapidly in young adult Alaskans aged 20-39. 

Distribution of cases compared to population distribution and distribution of cases, hospitalizations and deaths by race and ethnicity

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. One factor limiting interpretation is that a greater proportion of tests from the Alaska Native Tribal Health system currently have race indicated than tests from other sources, which may mean that cases in Alaska Native People are more likely to be reported as such than cases in people who receive care through non-tribal health systems. However, this should not significantly impact Native Hawaiian and Pacific Islander population case counts. 

If race or ethnicity is not identified with the initial test, contact tracers will attempt to collect this information, but these data are often delayed resulting in many cases (currently 2,602, or 35%- improved 10% from last week) still labeled under investigation or unknown. Additionally, people who are hospitalized or have died with COVID-19 are more likely to have a race identified. Because many cases that previously had unknown race or ethnicity now have an identified race or ethnicity, numbers of cases in different race and ethnicity categories have increased since last week beyond the number of new cases, so these numbers affect both newly diagnosed and newly categorized but previously counted cases. 

Race Percent of Alaska population*Number of casesPercent of cases of those for whom a race is knownIn cases of that race/ethnicity, percent who were/are hospitalizedIn cases of that race or ethnicity, percent who have died
American Indian and Alaska Native15.6%1,90428.5%4.9% 1.1% 
Asian6.5%3925.9%5.6% 1.0% 
Black/African American3.7%3765.6%2.1% 0.5%
Hispanic ethnicity**7.3%69912.3%***2.7%0.1%
Multiple races7.5%3625.4%3.0%0%
Native Hawaiian and Pacific Islander1.4%4486.7%11.4% 1.6% 
White65.3%2,89343.3%2.9%0.8%
Other 3084.6%3.6% 0%
Unknown or not yet identified 1,930 1.1% 0.1%
All cases for whom a race is known 6,683 4.2%0.9%
All cases 7,481 3.5%0.7%

*Based on US Census Bureau 2019 estimates: https://www.census.gov/quickfacts/AK

**By federal convention, ethnicity is not mutually exclusive of race, so cases identifying Hispanic ethnicity are also counted under a race category.  

***Reports the percent of cases of those for whom an ethnicity is known.

Distribution of cases compared to population distribution and distribution of cases, hospitalizations and deaths by age group

Age group (years)Percent of Alaska population*Number of casesPercent of casesIn cases of that age group, percent who were/are hospitalizedIn cases of that age group, percent who have died
<1014.2%4405.1%0.7%0%
10-1913.3%88910.3%0.2%0%
20-2915.2%2,12524.7%0.8%0%
30-3914.7%1,63319.0%1.6%0.1%
40-4911.7%1,16013.5%3.5%0.3%
50-5912.8%1,11412.9%4.8%0.5%
60-6911.3%7759.0%7.5%1.4%
70-794.7%3353.9%19.1%6.3%
80+~2%**1421.6%25.4%9.9%
All cases 8,613   

*Based on US Census Bureau 2019 estimates via Census Reporter: https://censusreporter.org/profiles/04000US02-alaska/

**Margin of error is at least 10% of the total value

Cases by age

Note: Weeks of the year are numbered in the graph above; W39 refers to the week of September 21-September 27, 2020. 

Distribution of cases compared to population distribution and distribution of cases, hospitalizations and deaths by sex

SexPercent of Alaska population*Number of casesPercent of casesIn cases of that age group, percent who were/are hospitalizedIn cases of that age group, percent who have died
Male52%4,34250.4%3.8%0.9%
Female48%4,27149.6%3.2%0.5%

*Based on US Census Bureau 2019 estimates via Census Reporter: https://censusreporter.org/profiles/04000US02-alaska/

Testing trends

  • Testing increased at a steady rate throughout May, June and July, slowed in mid-August, and is starting to increase again. Nearly half a million tests have been performed so far in Alaska (476,818) and current laboratory turnaround times average 1-2 days. 
  • Alaska has the capacity to continue expanding testing. DHSS can assist in materials for setting up new testing sites and is pursuing all avenues for expanding testing. 

Positivity rates

  • The statewide test positivity rate went from 2.4% to 3.9% this week, which is the highest it has ever been. Positivity rate is calculated by dividing the number of positive tests by the total number of tests performed over a given period of time, averaged over the past seven days. Statewide test positivity had not been above 3% since April, and has never before exceeded 3.5%, but has been climbing from below 2% in early September and the increase has accelerated.  
  • Currently, the national average is 4.6%. While many states have a higher positivity rate than Alaska does, this rise is concerning because the positivity rate is our best measure of whether our testing capacity can keep up with current cases. A rise in positivity rate reflects that testing is not increasing as fast as the current increase in cases. Since Alaska’s per-capita testing capacity is more robust than almost any other state, the finding that the positivity rate is nearing the national average is concerning. Source: Johns Hopkins
  • Of boroughs or census areas in the high risk zone, the reported test positivity rate is currently highest in the Fairbanks North Star Borough, with a rate of 10.5%, nearly double their rate of 6.0% last week. Anchorage Municipality has a test positivity rate of 4.6, an increase from 2.8%. The North Slope Borough’s reported test positivity rate is currently 19.2%, which is very concerning, although is limited by being based on a smaller number of tests. The Northwest Arctic Borough’s positivity rate is reported as 6.4%. Kusilvak Census Area also reports a high positivity rate but this is based on such a small number of tests that the data is not currently considered complete.
  • Test positivity is a good measure of whether testing is adequate in a given area, since it is affected by the number of tests performed as well as the number of new cases in an area. However, because it depends so much on the number of tests performed, it tells us more about whether we are doing enough testing than about how much virus is spreading in a community. It cannot be used to compare the amount of virus spread in one state to another, but it can be used to compare whether different states are doing adequate enough testing to be able to measure their case rate. It is also affected by any delays in reporting, since positive tests are sometimes reported faster than negative tests. A case rate can give good information about how much virus is spreading in a community, as long as the test positivity is low, so these measures can work together to help us understand the spread of virus in a community. A community test positivity rate under 5% is currently generally accepted as being low enough to estimate that a community’s case rate is reasonably accurate. 
  • In late August, Alaska led the nation in most tests per capita and continues to be among the top 3 states in tests per capita. Alaska’s high testing rates likely affect our hospitalization and death rates, since in places where tests are restricted to people who are very ill, many asymptomatic or mildly symptomatic COVID-19 cases are missed. In Alaska, testing is somewhat more available in many communities than in many communities in the lower 48, so we may detect more COVID-19 cases relative to the real number of people with COVID-19 than in states that do less testing per capita. Hospitalization and death rates are calculated by dividing the number of people who were hospitalized or who died by the number of people in that group that were known to have COVID-19, regardless of the severity of their illness. 
  • We do not have a reason to believe that the strains of COVID-19 are any less virulent in Alaska than elsewhere; in fact, in the genetic studies done so far of COVID-19 strains circulating in Alaska, virus that was as virulent or more so than that circulating in the Western United States was identified. This means that the virus present in many communities in Alaska has the ability to make people of all ages very sick if it is allowed to continue to spread. 

Health care capacity

  • Due to a change in hospital reporting in late September, hospital data on the data hub no longer reflects inpatient and ICU beds available for adult patients. This change resulted in hospitals reporting infant beds, including infant ICU beds (NICU beds) in the total beds available, increasing the total number of beds counted. However, since the beds newly added to the total do not reflect beds that can be used for adults or older children, the current method of hospital reporting is not as useful for determining the capacity in the state should an increased number of adults or older children require inpatient or critical care. While DHSS is working towards a hospital data hub that better reflects the state’s real capacity to respond to increased COVID-19 hospitalizations, the current data is available on the data hub but should be viewed with these caveats in mind. Additionally, hospital data includes inpatient beds and ventilators located all around the state, including some in smaller hospitals without ICU capacity. Hospital beds also do not necessarily represent staffed beds, as staffing can change quickly, particularly if a community has many health workers impacted by COVID-19. 
  • Currently, 45 Alaskans with suspected or confirmed COVID-19 are hospitalized. Of these, 6 are currently requiring a mechanical ventilator. 

COVID-19 and travel

  • Travel is not currently thought to be a main factor in most new COVID-19 infections in Alaska, meaning that most Alaskans who get COVID-19 are getting it from social, work or family contacts rather than travel. New cases in nonresidents have diminished and have averaged fewer than three new cases per day over the last few weeks.
  • Testing in airports is now in its 17th week, with 314,981 passengers screened total, 13,824 in the past week. In the last week, 5,935 (43%) of travelers tested prior to travel, 5,027 (36%) tested in the airport, 1,229 (8.9%) selected a 14-day quarantine and 1,663 (12%) followed another workplace and community protection plan. Of those tested in AK airports, 51 were positive, for a 1.0% positivity rate. Since airport testing began, 159,293 (51%) of travelers have tested prior to travel, 96,882 (31%) have been tested in an airport in Alaska, 32,081 (10%) have selected a 14-day quarantine, and there have been 514 positive tests overall.
  • The positivity rate in airport tests has more than doubled from 0.4% to 1.0% in the last two weeks, a concerning rise.
airport percent positivity
positive tests from airport testing
airport 3

What Alaskans should do 

  • 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.

 Further information

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