Contact tracing is not for all?

One aspect that stands out in this year of pandemic, which has gripped the entire world, is that related to the different effectiveness in terms of results and use of contact tracing in the various countries of the world. In some cases there have been effective contact tracing interventions, while in other cases we have witnessed a partial or total failure of contact tracing.

The causes for the deficiency are variable and structural. Old technologies and underresourced health care services have tended to be unwell to respond. Advanced economies have suffered to recruit enough contact-tracers, to spearhead them properly, or to assure that people are self-isolated when they are infected or quarantine when they are in near contact with the disease. And overburdened contact-tracers have been met with suspicion by people who are dubious of both the health authority and the tools used to tackle the pandemic. Even so, researchers who are keen to learn from contact-tracing operations are impeded by a lack of data.

A handful of countries pop out as models of effective contact-tracing, including South Korea, Vietnam, Japan and Taiwan. Many of them are clamping down relatively early, isolating infected persons and their contacts and then using personal data such as cell phone signals to reliably detect compliance. Not all of these strategies are generalizable to nations that are still trying to control major outbreaks.

Interventions that help involve tracing several levels of contacts, investigating disease outbreaks and supplying individuals who are recommended to quarantine with secure areas to do so and financial reimbursement. Technology may also make things better: from software that optimizes conventional contact tracing activities to smartphone apps that notify people that they may have been exposed to SARS-CoV-2.

The WHO benchmark for outstanding COVID-19 contact-tracing activity is to detect and quarantine 80 percent of near connections within 3 days of the case being certified, target that few countries accomplish.

There are ways in which contact-tracers could get rid of a quickly spreading epidemic. One is to lay a larger net around each case, such that second-order contacts are identified and quarantined.

A further effective technique is to trace the contacts of a new patient back as much as 15 days until they got the virus, to determine who infected them. This 'backwards contact tracing' is particularly successful for coronavirus addition to its potential to be transmitted to superspreading scenarios.

Any new case is often more probable to have arisen from a cluster of infections than from a person, so there is sense in looking backwards to figure out who else was exposed to the cluster.

For contact-tracing to succeed, people with COVID-19 need to be able to address questions about where they are and they need to be separated from others if they are not well. It doesn't happen in so many parts of the world.

Many health agencies and authorities, mainly in North America and Western Europe, will need to enhance public health communications as a matter of priority to reduce contact-tracing fears. Systems are also hindered by a lack of care for people who are sick or need to quarantine. Providing sufficient financial coverage for personal suffering as a consequence of quarantine might change people's unwillingness to obey. The possibility of being without income for two weeks, or of losing an employment altogether is a major burden and may justify people's hesitation to share information about their close connections.

If Western nations are not so inclined to support case isolation, quarantine contacts individually or take digital action to detect infected, we might wonder if contact tracing is up to the job of stifling the spread of COVID-19 in these places, if that work, as it is now, is striving to reduce the amount of cases.