New App for Tracking Possible COVID-19 Exposure in Arizona

 

The other day, a notification popped-up on my phone asking if I wanted to install this app called Covid Watch Arizona. Naturally, I accepted.

This technology has been around for some time. Similar system are in place in (at least) Virginia and New York.  

With this app (available from the Play Store or the App Store) your phone has anonymous Bluetooth conversations with other phones nearby so it knows what phones it has been near. When the owner of one of those phones reports an infection, others who were near it are notified.

This does not involve any central repository of what phones were near other phones. Your phone keeps the list of anonymous ID numbers of the phones it was near and only alerts you when it receives word that one of those IDs has an infected owner. 

It's not totally clear to me who is behind the development and deployment of the app in Arizona. As you can see from the screenshot above, it is listed as belonging to AzDHS. But the University of Arizona has a page describing it as "the Univesity's anonymous exposure notification app."  

Yet another page says it was developed by WeHealth. There is not much indication on their site of  where they are based, but based on news releases that they must have some connection to U of A.

One trial of such an app was done in the UK. According to an article in Nature, About 28% of the population has the app installed. Researchers estimate that above a minimum of 15%, every 1% increase in adoption reduces the number of infections by 0.8–2.3%. They note that "it is difficult to conclude that infections and deaths were averted because people used the app" because there are other forms of contact tracing in the UK.

These adoption figures are the rub. Without a substantial number of people using the app, it won't detect much, and we don't know how many people have it installed.  You can see from the screenshot that only 176 Android users have reviewed it. That figure is 84 for the Apple app store. 

I'm not quite sure how that notification inviting me to install the app made its way to my screen. Hopefully if that somehow went out to all Arizonans, a lot of people accepted. 

So far I've had no exposures reported. I will update if that changes.

 



Popular posts from this blog

Looks Like Immune Responses are Enduring After All

Image
 For some time, public health officials have fretted about whether immunity to COVID-19, acquired via infection or vaccination would stick.  Studies showed rapid declines in antibodies during recovery from infection and thereafter . It turns out that this concern was overblown. A study just released says bone marrow plasma cells are a persistent source of protective antibodies, and that "circulating resting memory B cells directed against the S protein were detected in the convalescent individuals."   Another study , yet to be reviewed, suggests that vaccines boost this effect. In fact, some are suggesting this situation this could actually mean  lifetime immunity .   Whether the same thing happens with vaccination is not clear. Most estimates suggest that vaccine immunity will last about a year . More pessimistic estimates putting the protection period at six months .  The possible shorter time frame, plus the appearance of the new variants, have the vaccine makers working
Read more

Another One Bites the Dust

Image
Hi all. Stepping out of retirement for a moment to say that the day has finally arrived. After four years of successfully avoiding COVID-19 infection I had a positive test yesterday. Symptoms are very mild—I've had worse colds. The provider at urgent care said almost all the cases they are seeing are the same. Mild symptoms may also be due to the fact that I had the original vaccine then the two boosters. All this time I thought I might be a NOVID —one of those people who never get the bug. But no, it must have been my assiduous mask wearing and avoidance of high-risk situations when things were bad. So here's double middle fingers to all the kooks who think masks don't work (I've not been wearing masks for months now). I don't know what variant I have but it's likely JN.1. It is said to be extraordinarily contagious and accounts for 60% of cases worldwide . It also tends to produce mild infections like the one I have.  This article claims that right now every
Read more

Anti-Mitigation Groups Have Formed a Death Cult

Image
Over the weekend anti-vax protestors showed up at Los Angeles's Dodger Stadium, the largest vaccination site in the country, and staged a protest . Police said the protest was peaceful.  But the fire department closed the entrance to prevent them from moving onto the grounds or getting killed by traffic. In the end they didn't prevent anyone from getting a vaccination who had an appointment, but they did hold up the line for about an hour. In my option, these protestors are very lucky the people waiting in line didn't jump out of their cars and beat them senseless.   You have to wonder what these crackpots thought they would accomplish with their protest. People who are there already accept the truth that vaccines are protective, and don't think COVID-19 is a hoax. Did they think they would win converts? It was a fool's errand, kind of like holding an atheism demonstration outside the entrance to St. Peter's. Now it seems that the anti-vaxxers are increasingly j
Read more