Monday, May 18, 2020

TESTING-ISOLATING-CONTACT TRACING: How it Works and Why it Matters

by Brian T. Lynch, MSW

The daily testing numbers for COVID-19 actually shrank from the Saturday numbers in some sort of correction on the WorldoMeter.info site. The US consistently ranks about 39th out of the 212 nations and territories reported in the statistics. The total number of tests performed to date isn't enough to cover more than 3.6% of our population. Here is why this matters, and why experts say we need a minimum of 10 times more testing PER DAY than we have now.

TESTING - ISOLATING - CONTACT TRACING
      
       NOTE: 
Isolation is the term used when people with symptoms are kept away from the publicQuarantine is the term used when people have been exposed but are asymptomatic

In the absence of a vaccine or effective treatment/prevention for COVID-19, the best way to get our infection rates (and death rates) under control is by testing people for the virus, isolating those who have symptoms or quarantining those who test positive, and by tracing their contacts to test them for the virus. This is the way this works to the best of my layman understanding.

1. TESTING - We need to test as many people as possible, at least millions of people per day. We need those test results to be returned immediately or ask people to self-isolate until the results are returned. If they test negative they are able to engage in the reasonable social distancing and prevention measures being advocated by the CDC. (ie: wearing masks, maintaining social distances, frequent hand washing, limiting the size of social gatherings, etc. Retesting at an appropriate interval will be required. For example, healthcare workers and first responders would need frequent testing while retirees living at home and mostly staying away from public venues would require less frequent testing.

2. ISOLATING - When a person tests positive for COVID-19 and has symptoms, they should be isolated from everyone, including their family. If they test positive but don't have symptoms they should go into quarantine for a minimum of 14 days (some researchers are suggesting a longer quarantine period). The must also be interviewed to see who they may have been in close proximity to in the prior days. (I don't know how long the lookback is.)

3. CONTACT TRACING - A team of contract tracers then determines who is at risk of contracting the virus based on the interview with an infected person and visits those potentially exposed people. These people should self-quarantine until they can be tested for COVID-19. And so the whole cycle of testing, isolating, and contract tracing continues forward.

This is how we can safely begin to reopen the economy and society while reducing the rate of infections and deaths. The key first step is adequate testing with rapid results. If we set a national goal of testing every person in the US for COVID-19 over the next 3 months, that would require administering 3.7 million tests per day. This is about 10 times the current daily average.

The next step is to hire and train a huge number of the currently unemployed people in this county to become COVID-19 test administers and contact tracers. With unemployment at record highs and so many people out of work, and with the country facing a possible "Great Depression" it should be the federal government hiring an army of contact tracers to help control the pandemic while stimulating the economy, as the WPA did 85 years ago.

Here below is a list of suggested readings with a brief synopsis:

Coronavirus: why testing and contact tracing isn’t a simple solution
://theconversation.com/coronavirus-why-testing-and-contact-tracing-isnt-a-simple-solution-137214
Talks about the limitations of testing and contract tracing and the conditions when a lockdown is needed. Gives examples of how many COVID-19 tests were needed per case in countries that were able to use this technique to control the outbreak (between 52 and 64 tests per case).


Effectiveness of isolation, testing, contact tracing and physical distancing on reducing transmission of SARS-CoV-2 in different settings

https://www.medrxiv.org/content/10.1101/2020.04.23.20077024v1
Abstract: "... Consistent with previous modeling studies and country-specific COVID-19 responses to date, our analysis estimates that a high proportion of cases would need to self-isolate and a high proportion of their contacts to be successfully traced to ensure an effective reproduction number that is below one in the absence of other measures. If combined with moderate physical distancing measures, self-isolation and contact tracing would be more likely to achieve control."

Contact Tracing: Part of a Multipronged Approach to Fight the COVID-19 Pandemic
https://www.cdc.gov/coronavirus/2019-ncov/php/principles-contact-tracing.htmlxcerpt: Contact tracing is part of the process of supporting patients and warning contacts of exposure in order to stop chains of transmission. Given the magnitude of COVID-19 cases and plans to eventually relax mitigation efforts such as stay at home orders and social distancing, communities need a large number of trained contact tracers. These contact tracers need to quickly locate and talk with the patients, assist in arranging for patients to isolate themselves and work with patients to identify people with whom the patients have been in close contact so the contact tracer can locate them. The actual number of staff needed is large and varies depending on a number of factors including but not limited to:
  • The daily number of cases
  • The number of contacts identified
  • How quickly patients are isolated, and contacts are notified and advised to stay home, self-monitor, and maintain social distance from others
HEALTH DEPARTMENTS: Interim Guidance on Developing a COVID-19 Case Investigation & Contact Tracing Plan
Provides a comprehensive plan for local authorities to establish a TICTs (Testing, Isolating, Contact tracing) plan. Excerpt: 

Contract Tracers: Communicates with contacts to notify them of exposure, provides disease and transmission information, gathers data on demographics, living arrangements, and daily activities. Asks about signs/symptoms and underlying medical conditions. Provides referrals for testing (if appropriate). May conduct home-based specimen collection. Provides recommendations for self-quarantine and reviews daily monitoring procedures. Assesses supports necessary to maintain compliance during self-quarantine. Conversations with contacts should be guided by standard protocols. Conducts daily monitoring during self-quarantine— temperature, signs/symptoms, use of fever-reducing medications—via an electronic tool (e.g., smartphone, case management software) or other designated mechanism, until 14 days after last potential exposure, and referral to healthcare if contact becomes symptomatic.**

What Is Contact Tracing? Here's How It Could Be Used to Help Fight Coronavirus
https://time.com/5825140/what-is-contact-tracing-coronavirus/
EXCERPT:

Once someone has been confirmed to be infected with a virus, such as through a positive COVID-19 test, contact tracers try to track down others who have had recent prolonged exposure to that person when they may have been infectious. Typically, that exposure means being within 6 feet of the person for more than 10 minutes, says Dr. Breeher, though in a health care setting, such as a hospital, the bar is lowered to five minutes.

Healthcare workers then make an effort to reach out to every one of those contacts, tell them that they may have been exposed, and giving them instructions on what to do next. That may include telling them about possible symptoms or directing them to self-isolate [ie: Quarantine].

What is contact tracing?https://www.theverge.com/2020/4/10/21216550/contact-tracing-coronavirus-what-is-tracking-spread-how-it-worksExcerpt: Contact tracing is based on an obvious idea: people in close contact with someone who has COVID-19 are at risk of getting sick. The process isn’t easy. When a person gets sick, they are then interviewed by public health officials and asked who has been exposed to them. Then they take that list and fan out to ask those people either to pay close attention to how they’re feeling or to quarantine. If a person who was exposed is infected, their recent contacts will be tracked down, too. The process continues until everyone who’s been exposed is out of circulation. That stops virus transmission.

1 comment:

  1. TESTING-ISOLATING-CONTACT TRACING: How it Works and Why it Mattershttps://aseyeseesit.blogspot.com/2020/05/testing-isolating-contact-tracing-how.html

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