We may well be able to eliminate coronavirus, but we’ll probably never eradicate it. Here’s the difference



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Adrian Esterman, University of South Australia

Compared to many other countries around the world, Australia and New Zealand have done an exceptional job controlling COVID-19.

As of May 7, there were 794 active cases of COVID-19 in Australia. Only 62 were in hospital.

The situation in New Zealand is similar, with 136 active cases, only two of whom are in hospital.

If we continue on this path, could we eliminate COVID-19 from Australia and New Zealand?




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Control –> elimination –> eradication

In order to answer this question, we first to need to understand what elimination means in the context of disease, and how it differs from control and eradication.

Disease control is when we see a reduction in disease incidence and prevalence (new cases and current cases) as a result of public health measures. The reduction does not mean to zero cases, but rather to an acceptable level.

Unfortunately, there’s no consensus on what is acceptable. It can differ from disease to disease and from jurisdiction to jurisdiction.

As an example, there were only 81 cases of measles reported in Australia in 2017. Measles is considered under control in Australia.

Conversely, measles is not regarded as controlled in New Zealand, where there was an outbreak in 2019. From January 1, 2019, to February 21, 2020, New Zealand recorded 2,194 measles cases.

For disease elimination, there must be zero new cases of the disease in a defined geographic area. There is no defined time period this needs to be sustained for – it usually depends on the incubation period of the disease (the time between being exposed to the virus and the onset of symptoms).

For example, the South Australian government is looking for 28 days of no new coronavirus cases (twice the incubation period of COVID-19) before they will consider it eliminated.

Even when a disease has been eliminated, we continue intervention measures such as border controls and surveillance testing to ensure it doesn’t come back.

For example, in Australia, we have successfully eliminated rubella (German measles). But we maintain an immunisation schedule and disease surveillance program.




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Finally, disease eradication is when there is zero incidence worldwide of a disease following deliberate efforts to get rid of it. In this scenario, we no longer need intervention measures.

Only two infectious diseases have been declared eradicated by the World Health Organisation – smallpox in 1980 and rinderpest (a disease in cattle caused by the paramyxovirus) in 2011.

Polio is close to eradication with only 539 cases reported worldwide in 2019.

Guinea worm disease is also close with a total of just 19 human cases from January to June 2019 across two African countries.

What stage are we at with COVID-19?

In Australia and New Zealand we currently have COVID-19 under control.

Importantly, in Australia, the effective reproduction number (Reff) is close to zero. Estimates of Reff come from mathematical modelling, which has not been published for New Zealand, but the Reff is likely to be close to zero in New Zealand too.

The Reff is the average number of people each infected person infects. So a Reff of 2 means on average, each person with COVID-19 infects two others.

If the Reff is greater than 1 the epidemic continues; if the Reff is equal to 1 it becomes endemic (that is, it grumbles along on a permanent basis); and if the Reff is lower than 1, the epidemic dies out.

So we could be on the way to elimination.




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In both Australia and New Zealand we have found almost all of the imported cases, quarantined them, and undertaken contact tracing. Based on extensive community testing, there also appear to be very few community-acquired cases.

The next step in both countries will be sentinel surveillance, where random testing is carried out in selected groups. Hopefully in time these results will be able to show us COVID-19 has been eliminated.

The development of a vaccine can help control and eliminate a disease.
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It’s unlikely COVID-19 will ever be eradicated

To be eradicated, a disease needs to be both preventable and treatable. At the moment, we neither have anything to prevent COVID-19 (such as a vaccine) nor any proven treatments (such as antivirals).

Even if a vaccine does become available, SARS-CoV-2 (the virus that causes COVID-19) easily mutates. So we would be in a situation like we are with influenza, where we need annual vaccinations targeting the circulating strains.

The other factor making COVID-19 very difficult if not impossible to eradicate is the fact many infected people have few or no symptoms, and people could still be infectious even with no symptoms. This makes case detection very difficult.

At least with smallpox, it was easy to see whether someone was infected, as their body was covered in pustules (fluid-containing swellings).

So while we may well be on the path to elimination in Australia and New Zealand, eradication is a different ball game.




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The Conversation


Adrian Esterman, Professor of Biostatistics, University of South Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

VIETNAM: AUTHORITIES PRESSURE NEW CHRISTIANS TO RECANT


Converts from ancestral animism threatened with violence, imprisonment.

HO CHI MINH CITY, November 21 (Compass Direct News) – In violation of Vietnam’s new religion policy, authorities in Lao Cai Province in Vietnam’s far north are pressuring new Christians among the Hmong minority to recant their faith and to re-establish ancestral altars, according to area church leaders.

Local authorities have warned that on Sunday (Nov. 23) they will come in force to Ban Gia Commune and Lu Siu Tung village, Bac Ha district, where the Christians reside, but they did not say what they would do.

When the authorities in Bac Ha district in Vietnam’s Northwest Mountainous Region discovered that villagers had converted to Christianity and discarded their altars, they sent “work teams’ to the area to apply pressure. Earlier this month they sent seven high officials – including Ban Gia Deputy Commune Chief Thao Seo Pao, district Police Chief A. Cuong and district Security Chief A. Son – to try to convince the converts that the government considered becoming a Christian a very serious offense.

Christian leaders in the area said threats included being cut off from any government services. When this failed to deter the new Christians, they said, the officials threatened to drive the Christians from their homes and fields, harm them physically and put them in prison.

When the Christians refused to buckle under the threats, a leader of the Christians, Chau Seo Giao, was summoned daily to the commune headquarters for interrogation. He refused to agree to lead his people back to their animistic beliefs and practices.

Giao asked the authorities to put their orders to recant the Christian faith into writing. The officials declined, with one saying, “We have complete authority in this place. We do not have to put our orders into writing.”

They held Giao for a day and night without food and water before releasing him. He is still required to report daily for “work sessions.”

In September, Hmong evangelists of the Vietnam Good News Church had traveled to the remote Ban Gia Commune where it borders Ha Giang province. Within a month, some 20 families numbering 108 people in Lu Siu Tung village had become Christians and had chosen Giao to be their leading elder.

Rapid growth of Christianity among Vietnam’s ethnic minorities in the northwest provinces has long worried authorities. There were no Protestant believers in the region in 1988, and today there are an estimated 300,000 in many hundreds of congregations. As recently as 2003, official government policy, according to top secret documents acquired by Vietnam Christians leaders, was the “eradication” of Christianity.

Under international pressure, however, a new, more enlightened religion policy was promulgated by Vietnam beginning in late 2004. Part of the new approach was an effort to eliminate forced renunciations of faith. The provisions and benefits of such legislation, however, have been very unevenly applied and have not reached many places such as Ban Gia Commune.

Vietnam’s Bureau of Religious Affairs prepared a special instruction manual for officials in the Northwest Mountainous Region on how to deal with the Protestant movement. Published in 2006 and entitled “Concerning the Task of the Protestant Religion in the Northwest Mountainous Region,” this document included plainly worded instructions for authorities to use all means to persuade new believers to return to their traditional beliefs and practices.

This document directly contravened Vietnam’s undertaking to outlaw any forcible change of religion. Under international pressure, the manual was revised and some language softened, but according to an analysis of the 2007 revision of the manual released in February by Christian Solidarity Worldwide (CSW), the language still communicates the goal of containing existing Christianity and leaves the door open to actively stop the spread of Christianity.

The Central Bureau of Religious Affairs instruction manual for training officials shows no change to the 2006 document’s core objective to “solve the Protestant problem” by subduing its development, concluded the February report by CSW and the International Society for Human Rights.

The 2006 manual had outlined a government plan to “resolutely subdue the abnormally rapid and spontaneous development of the Protestant religion in the region.”

“Whereas the 2006 manual provided specific legitimacy for local officials to force renunciations of faith among members of less well-established congregations, the 2007 edition imposes an undefined and arbitrary condition of stability upon the freedom of a congregation to operate,” the CSW report says. “Therefore, the treatment of any congregation deemed not to ‘stably practice religion’ is implicitly left to the arbitration of local officials, who had previously been mandated to force renunciations of faith.”

Without a full and unconditional prohibition on forcing renunciations of faith, the report concludes, the amended manual does not go far enough to redress problems in the 2006 original.

Officials in the remote village of Ban Gia felt no compunction to resort to strong-arm methods to halt the growth of Christianity, said one long-time Vietnam observer.

“When a church leader advised the central government of the problem in Ban Gia Commune, the pressure only increased,” he said. “The unavoidable conclusion is that it is still acceptable in Vietnam for officials to force recantations of Christian faith.”

Report from Compass Direct News