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Saturday January 28th, 2023

What is contact tracing of Coronavirus

ECONOMYNEXT – Contact tracing combined with isolation and quick testing has been use to stop the progress of Coronavirus in several countries in Asia, with major progress being made when it was used early in the Covid-19 crisis.

Vietnam and Sri Lanka are among countries in the world that have used contact tracing and quarantine most effectively to stop the progress of Coronavirus.


How Sri Lanka and Vietnam are smashing Coronavirus, and what will happen next
How Sri Lanka and Vietnam are smashing Coronavirus, and what will happen next

Once an index case is found, contacts of the person is located, isolated/quarantined and tested. The contacts of contacts are also tested.

Vietnam and Sri Lanka has confined total cases found to a few hundred but there may be more out in the country.

For a crash course in contact tracing Coronavirus index cases and how to test contacts read this fast-tracked article at International Journal of Tuberculosis and Lung Disease (IJTLD)

Contact tracing is an old tactic used by health services to fight epidemics spread by human-to-human contact ranging from Tuberculosis to Ebola.

Unlike TB, Coronavirus spreads very fast, so contact tracing has to be quick. Unlike Ebola there is no fever in all patients so contacts have to be tested fast to find whether it has infected the next level of contacts.

Since contacts expand exponentially (community transmission) the disease can quickly get out of control.

Nigeria used contact tracing against Ebola very successfully from the index case Patrick Sawyer which was recognized as world-class epidemiological detective work.

But unlike Ebola where symptoms come up fast Coronavirus has asymptomatic cases.

When community transmission is widespread it is difficult to trace patients back or forward. Whe public services collapse once community transmission takes place all efforts are put to mitigation.

A person who comes from abroad carrying the virus (or the person who got the diseases in Wuhan supposedly from an animal) is the index case or F0. The contacts of F0 are F1. The contacts of F1 are F2. Contacts of F2 and F3.

In Sri Lanka they are called Fist Ring, Second Ring, Third Ring.

If there is cluster of several levels, the entire area is surgically locked down until all contacts are identified or incubation period passes and they are tested. But there is evidence that some people get infected as late as three weeks after contact.

Sri Lanka has extended quarantine to three weeks.

Researchers from Woolcock Institute of Medical Research, Hanoi, Viet Nam; Sydney School of Medicine, The University of Sydney, Australia including T A Nguyen, Q N Cuong, A L T Kim, T N Huong, H N Nguyen, G J Fox, G B Marks, have shown in a recent publication how contact tracing should be combined with testing of contacts of index cases to quickly stop the spread of virus.

“First, three generations of contact (F) with COVID-19 cases should be traced to offer timely testing if the previous contact generation is found positive,” the researchers say in the fast-tracked paper in the International Journal of Tuberculosis and Lung Disease.

“All F1 contacts should be tested for SARS-CoV-2 regardless of symptom presentation.

“F1 individuals who are asymptomatic or have two negative tests 24 hours apart should be quarantined for 14 days.”

“F2 contacts should self-isolate at home and be monitored by public health units. If F1 tests positive, we recommend that F3 contacts should also be identified. When the previous F becomes positive, the next one will be informed to follow the contact management procedure.”

Contact tracing flow diagram drawn TA Nguyen et al.

Because it is believed that persons develop the disease as closely as two days, Coronavirus can spread rapidly to the next level. But if they are traced quickly and the levels identified the expanding line of transmission or cluster can be stopped.

All quarantined persons should also be tested before at least twice according to the process followed y by Sri Lanka and almost from the beginning in Vietnam.

To be successful, contact tracing has to start early, when foreign returnees first start coming. The later arrivals are blocked, the more difficult it is to contain community transmission.

Sri Lanka and Vietnam both quarantined and effectively killed the Wave I from China from all available evidence.

Sri Lanka found one patient from Hubei province in China. Vietnam found 16 during January and February 2020.

Wave I is the infection that spread from China to third countries. Any country that restricted arrivals from China, quarantined those that came, and stopped community transmission from Wave I, also stopped the of export of their citizens with Coronavirus to third countries.

Wave II is the pandemic where third countries came back to infect a country. Researchers are now thinking that the SARS-CoV-2 virus may be as old as September 2019.

Any country that allowed returnees to come from China without quarantine (either Chinese or their own citizens) let community transmission to take place in the Wave I epidemic. They then re-exported their citizens to contribute to the Wave II pandemic.

Sri Lanka and Vietnam closed airports for inbound traffic as quarantine became full endangering the contact tracing and isolation process as systems got overwhelmed.

They tightened border controls against the advice given by the WHO at the time.

Read: Updated WHO recommendations for international traffic in relation to COVID-19 outbreak

Both countries also stopped the Wave I from China with minimum controls against China, stopped community transmission and did not contribute to the pandemic that followed by exporting their citizens as far as is know.

It raises questions about exiting strategies followed in not quarantining all arrivals when unknown diseases are found. (Colombo/Apr18/2020)

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Sri Lanka utility to continue power cuts, regulator says no

ECONOMYNEXT – Sri Lanka’s state-run Ceylon Electricity Board has decided to continue power cuts, as the dry season hits the country despite orders to give 24 hours of power.

The utility said its Board “has decided to continue the demand management programme” and it has informed the regulator of this decision on January 27.

The Public Utilities Commission of Sri Lanka said it had not approved the power cuts “as it violate and affect the rights of 331,000 students sitting for the Advanced Level exams.”

Sri Lanka’s CEB has high running costs due to long term scuttling of planned coal plants by activists and lastly President Maithripala Sirisena.

‘CEB’s costs went up as demand went up since the last coal plant opening and steady collapse of the currency from 131 to 182 to the US dollar due to open market operations unleashed to suppress rates and operate a flexible inflation targeting by the central bank.

Even more aggressive liquidity injections after 2020 to target an output gap then busted the currency from 182 to 360 to the US dollar.

CEB has to use extra fuel from around February to April 2022 as the dry season hits reducing hydro power.

Sri Lanka’s Human Rights Commission has ordered the Ceylon Petroleum Corporation to supply fuel and banks to give credit for extra power.

Power Minister Kanchana Wijesekera has alleged that CPC officials agreed under duress and threat of jail sentence to supply fuel.

The CEB has to cut power in case demand outstrips supply to maintain frequency at 50 Hz to avoid cascading failures, according to sector analysts. (Colombo/Jan28/2023)

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Sri Lanka president suspends parliament till Feb 08

ECONOMYNEXT – Sri Lanka President Ranil Wickremesinghe has suspended parliament till February 08, according to a gazette notice.

Parliament will re-convene at 1000 am on January 08.

President Wickremesinghe told party leaders that he would make a speech, officially declaring his intention to give effect to the 13th amendment to the constitution on provincial councils.

Provincial councils, a power sharing arrangement backed by India as a solution to the ethnic Tamil have not yet been given police and land powers. (Colombo/Jan28/2023)

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Sri Lanka expects influx of global twins

ECONOMYNEXT – Sri Lanka’s expecting thousands twins and non-twin visitors including at least thirty contestants for a Twins Miss and Mr World 2023 contest, where they will join their counterparts in the country.

“We expect upwards of 4000 participants to arrive in the country for the event,” Founder and Chairperson Vice President Global Twins Multiple Birth Forum, Upuli Gamage told reporters.

“And we very much hope that this number will keep going up in the years to come.”

The country amidst an economic crisis is celebrating the Twins Miss & Mr World 2023 for the first time in the World in Sri Lanka to grab the attention of more than 30 countries.

Prospective Sri Lankan twins can apply for the local contest to be held in May. Winners will go the international event in July.

Twins contests are being held in 30 other countries and three participants will come from each country, according to the organizers.

“This event helps to build a positive image of the country while grabbing the attention of 50 countries,” Chairman Sri Lanka Tourism Promotion Bureau, Chalaka Gajabahu said.

“And I heard this can be go as a World record to the genus book, that will give country free PR, free digital media marketing, free social media marketing.”

The Sri Lankan Twins Organization along with the tourism authority has initiated this program including twins of this country as a promotional campaign in hopes of bringing in foreign revenue.

There will be series of events commencing from July 24 to 31 including a business forum for investors to interact. Visitors fro 30 countries are expected.

“Countries like Japan do such programs often and we too should, to grab foreign attention,” Consul General to Japan, Sunil Gamage said.

“This will help to build International bonds. This is an opportunity to bring investors.” (Colombo/Jan27/2022)

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