How a random sampling regime could help detect COVID and highlight infection hotspots

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Stephen John Haslett, Massey University and Richard Arnold, Te Herenga Waka — Victoria University of WellingtonFor the detection of community transmission of COVID-19, New Zealand currently relies on contact tracing, testing of self-selected people with symptoms and those with permission to travel between different alert levels, and surveillance testing of staff at businesses permitted to operate in higher alert levels.

Surveillance testing has picked up cases before they knew they were contacts of another infected person. But people who are only tested after they feel unwell may have already passed the virus on to several others. Others who have COVID-19 may not display symptoms.

As a supplement to current testing, we suggest a sound, properly designed random sampling regime of certain areas or workplaces to provide a cost-effective way to determine, with known probability, if there is any COVID-19 in a specified area or group.

The critical point is that such COVID Clearance Check surveys must be random.

Continued wastewater testing, contact tracing and community testing stations remain critically important. But they don’t provide any measures of accuracy because currently they don’t incorporate formal sampling designs.

Probability theory behind random sampling

A statistically designed random sampling scheme, based on as few as 100 people or households from key sub-populations, would give a very high probability of detecting if there are any COVID-19 cases. However, to determine this probability, it is critical the sampling is random.

Geographical locations could include certain neighbourhoods and wastewater catchment areas. Workplace sampling could focus on large businesses, rest homes, hospitals and prisons.

COVID Clearance Checks based on random sampling could shorten lockdowns, lessen social impact, save money and support businesses. Once Aotearoa’s borders reopen, they would provide critical information of known accuracy about infection hotspots.

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The formal sampling scheme is based on probability theory, which provides the mathematical connection between COVID prevalence (p₀), sample size (n) and the probability of detecting the virus in the subpopulation (p).

Unless a subpopulation is very small, its size has little effect on the sample size required. For a simple random sample, which selects people or households essentially independently and with equal probability, the probability of detecting COVID is:

p = 1-(1-p₀)ⁿ

For example, for a 3% prevalence of COVID and a random sample of 100, the chance of detecting the virus is over 95%. A larger sample would be required to detect COVID at lower prevalence, for clustered random sampling schemes, or for higher levels of detection probability.

Instead of simple random sampling of households, systematic sampling (which selects households at a fixed interval in a list or along a route) could be used to simplify fieldwork without loss of accuracy.

Survey design and structured fieldwork would provide the mechanism for implementing the random selection of people and safe work conditions for the sampling team. For random sampling, this is now feasible because saliva tests have recently been approved by the Ministry of Health.

Using self-administered saliva tests would reduce close contact between field staff and household members, minimising the risk of spread.

New Zealand has approved the use of rapid antigen testing as a screening tool to protect critical worksites.
Phil Walter/Getty Images

How it would work

Examples where a COVID Clearance Check survey would be useful include towns or city suburbs, and households in catchment areas with positive wastewater results. Sampling areas around MIQ facilities, but not including them, would provide information on possible community transmission.

As a first step, the Ministry of Health would identify particular areas or groups of interest, and then randomly select a sample within it, using statistically sound methods, to ensure every person had a known non-zero chance of being included.

For area sampling, having pre-notified residents, field staff would drop off saliva tests at each sampled household. Household tests would then be collected, either for separate individuals or combined, using set safety protocols.

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Read more:
Antigen tests for COVID-19 are fast and easy – and could solve the coronavirus testing problem despite being somewhat inaccurate

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Any selected households which do not return test results would be contacted again to reduce non-response bias. Any detected cases would bring other current control mechanisms into play.

Detecting all cases in an area is different and more difficult than detecting whether there are any cases. Cases detected by COVID Clearance Check sampling provide a searchlight rather than fully illuminating the situation. Finding all cases would require much larger sample sizes, which is why such checks supplement rather than replace current surveillance methods.

Using well-designed and implemented random sampling schemes can be an effective, rapid and low-cost way of assessing whether there are any community cases, without testing thousands of people who are not necessarily those of greatest interest. When useful, such surveys can be repeated, using another sample from the same area or group.

As we are now all realising, keeping COVID-19 out of Aotearoa cannot be a long-term plan. Once vaccination rates are high and borders begin to reopen, COVID Clearance Checks using random sampling to monitor possible hotspots will become increasingly useful, even necessary, for surveillance.

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Alistair Gray, at Statistics Research Associates, is also a member of the Ministry of Health COVID-19 Expert Advisory Network and has collaborated with us on this article.

Stephen John Haslett, Emeritus Professor of Statistics, Massey University and Richard Arnold, Professor of Statistics and Data Science, Te Herenga Waka — Victoria University of Wellington

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

Christians in Middle East Fear Violence from Anti-Quran Protests

Those in the West who provoke Muslim extremists are not the ones who will suffer, they say.

ISTANBUL, October 5 (CDN) — Christians across the Middle East said they will be the ones to suffer if a group of anti-Islamic protestors in the United States goes through with its plans to publicly tear up or otherwise desecrate the Quran.

They roundly condemned the proposed actions as political stunts that are unwise, unnecessary and unchristian.

“This kind of negative propaganda is very harmful to our situation in Muslim countries,” said Atef Samy, assistant pastor for networking at Kasr El Dobara, the largest Protestant congregation in Egypt. “It generates uncontrollable anger among the people around us and gives the impression that all Christians feel this way about Islam.”

Samy said U.S. Christians who are protesting Islam need to think about the results of their “irrational actions.” The desecration, he said, will lead to protests and will incite people to commit anti-Christian violence.

“How do they expect Muslims to react?” he said. “And has anybody thought how we will pay for their actions or even their words?”

Tomorrow and Thursday (Oct. 6 and 7), political activist Randall Terry will host “Hear Muhammad Speak!” a series of demonstrations across the United States that he said are meant to “ignite national and world-wide debate/dialogue/education on the anti-Semitic, anti-Christian, and at times violent message of the Quran.” During these protests, Terry plans to tear out pages from the Quran and encourage others to do the same.

He has said he is conducting the protest because he wants to focus attention also on the Hadith and the Sunnah, the recorded sayings and actions of Muhammad that Muslims use to guide their lives. Terry said these religious documents call “for the murder, beheadings, etc. of Christians and Jews, and the suppression of religious freedom.”

Known for his incendiary political approach, Terry is founder of Operation Rescue, an anti-abortion rights group. After stepping down from Operation Rescue, he publicly supported the actions of Scott Roeder, who murdered a Kansas physician who performed late-term abortions. Terry also arranged to have a protestor present an aborted fetus to then-presidential candidate Bill Clinton at the 1992 Democratic National Convention.

On this year’s anniversary of the Sept. 11 terrorist attacks, Terry stood outside the White House and denounced Islam as one of five other protestors ripped out pages from the Quran and threw them into a plastic trash bag, which along with Florida Pastor Terry Jones’ planned (though ultimately cancelled) Quran-burning provoked isolated attacks across the Islamic world that left at least 19 dead.

Terry is part of a seemingly growing tide of people destroying or threatening to destroy the Quran as an act of protest against Islam or “Islamic extremism.”

 

Objections

Terry has said that he wants to “highlight the suffering of Christians inflicted by Muslims” and to call on Islamic leaders “to stop persecuting and killing Christians and Jews, and well as ‘apostates’ who leave Islam.”

But Christian leaders in the Middle East said protests in which the Quran is desecrated have the opposite effect. They are bracing themselves for more attacks. Protestors in the West can speak freely – about free speech, among other things – but it’s Christians in the Middle East who will be doing the dying, they said.

“This message of hate antagonizes Muslims and promotes hatred,” said Samia Sidhom, a Christian and managing editor of the Cairo-based newspaper Watani. “Thus churches and Christians become targets of counter-hate and violence. Islam is in no way chastised, nor Christianity exalted. Only hate is strengthened. Churches and Christians here find they need to defend themselves against the allegations of being hateful and against the hate and violence directed at them.”

Martin Accad, a Lebanese Christian and director of the Institute of Middle East Studies at Arab Baptist Theological Seminary in Beirut, agreed with Sidhom.

“We are held guilty by association by extremist Muslims, even though the vast majority of Muslims will be able to dissociate between crazy American right-wingers and true followers of Jesus,” he said.

Leaders in the Arabic-speaking Christian world said Terry’s protests and others like it do nothing positive. Such provocations won’t make violent Muslim extremists re-examine their beliefs or go away.

“Islam will not disappear because we call it names,” said Samy, of the Egyptian Protestant church. “So we must witness to our belief in Jesus without aggressively attacking the others.”

Accad, a specialist in Christian-Muslim relations and also associate professor of Islamic Studies at Fuller Theological Seminary, said positive engagement is the best approach for Christians to take toward Islam.

“Visit their places of worship and get to know them, and invite them to yours,” Accad said. “Educate your own congregation about Islam in a balanced way. Engage in transformational partnerships with moderate Muslim leaders who are working towards a more peaceful world.”

The element of the protests that most baffled Christians living in the Muslim world was that burning or tearing another religion’s book seemed so unchristian, they said.

“In what way can burning or ripping the Quran serve Christianity or Christians?” Sidhom of Watani said. “It is not an action fit for a servant of Christianity. It merely expresses hate and sends out a message of extreme hostility to Islam.”

Accad called publicly desecrating the Quran an act of “sheer moral and ethical absurdity.”

“These are not acts committed by followers of a Jesus ethic,” Accad said. “They will affect the image of Christianity as badly as the destruction of the World Trade Center affected the image of Islam.”

Accad added, “Since when do followers of Jesus rip an eye for an eye and a tooth for a tooth?”

Such protests also defeat the purposes of churches in Islamic nations, Christians said. H. Ramdani, a church leader in Algeria, said Christians must strive to build bridges with Muslims in order to proclaim Christ.

“It’s destroying what we are doing and what we are planning to do,” he said of the protests. “People refuse to hear the gospel, but they ask the reason for the event. Muslims are more radical and sometimes they are brutal.”

At press time Compass was unable to reach Terry by phone or e-mail for a reply to the Middle Eastern Christians’ complaints about the planned protests, but after he staged a Sept. 11 Quran-tearing event he released a statement expressing “great sadness” over the deaths that followed while denying that it was right for Muslims to react violently to such protests.

“Such logic is like saying that a woman who is abused by her boyfriend or husband is guilty of bringing violence on herself because she said or did something that irritated him,” Terry stated.

In the weeks leading up to the anniversary of the Sept. 11 attack, Terry Jones, leader of a small congregation in Gainesville, Fla., made his mark in the media by threatening to burn a stack of Qurans in protest of Islam. At the last minute, after wide condemnation from around the world, Jones stated that he felt “God is telling us to stop” and backed out of the protest.

Despite Jones’ retreat, protestors unaffiliated with him burned Qurans in New York and Tennessee, and demonstrations swept across the Muslim world. In the relatively isolated attacks that ensued, protestors set fire to a Christian school and various government buildings, burning the school and the other structures to the ground. In Kashmir, 17 people were killed in Islamic assaults, and two protestors were killed in demonstrations in Afghanistan.

Report from Compass Direct News

Two Iranian Christian Women Acquitted of all Charges

Young converts previously held in prison for Christian activities have fled country.

ISTANBUL, May 27 (CDN) — Nearly five months after releasing them from prison, an Iranian court has acquitted two women of all charges related to being Christians and engaging in Christian activities.

Iranians Maryam Rostampour and Marzieh Amirizadeh Esmaeilabad were arrested on March 5, 2009 and detained on charges of “acting against state security,” “taking part in illegal gatherings” and “apostasy” (leaving Islam) under Iran’s Revolutionary Court system.

After nearly eight months, on Nov. 18, 2009 authorities released them conditionally.

Although the court hearing their case originally set April 13 as their trial date, Compass was unable to confirm on what date the two women were acquitted, nor the conditions of their acquittal.

Senior Iranian judges and officials repeatedly intimidated the two women and pressured them to recant their faith, according to a press statement by Elam Ministries last week.

“They were warned that any future Christian activity in Iran will be seriously dealt with,” according to the statement.

Elam Ministries said the two women had fled Iran on Saturday (May 22) to an undisclosed location and were recovering.

Another Iranian convert who was forced to flee his country under similar circumstances years ago told Compass that he believed the intense lobbying efforts to release and acquit the women brought the government to an unspoken “standoff” with Christian rights groups outside the country.

“I think the court just made a political decision, ‘We will let you go, but we will not allow you to stay in the country,’” said the Iranian Christian, who requested anonymity. “That’s a pretty old-fashioned procedure they have – ‘We will let you go if you leave the country. You can have your faith, but not here.’”

In general, when Iranian authorities arrest Christians, they release them on bail within a few weeks and keep their case files open, thus applying soft pressure while allowing them to continue living in Iran. In cases where the government wants to remove Christians from the country because of their Christian activities, authorities have handed the Christians their passports and documents and told them to leave.

Iran’s government views all Christian activities as foreign intervention and thus a threat to national security. The two women’s families had hired a private lawyer.

Since their release, the young converts to Christianity had been waiting for a trial date and decision from an Iranian court to decide their fate as Christians living their faith. During this time, sources said that authorities watched them closely and that the two women were under “pressure” and received threatening phone calls.

“The government would not want them to stay in the country as heroes,” said the Iranian Christian. “It would be better for the government if they left Iran and didn’t become a positive example for the rest of the Christian community in Iran. Otherwise they would create a precedent of [Christians] who have not denied their faith, who have been acquitted and still live as Christians inside the country.”

The two women thanked Christians who have been praying for them, according to Elam.

“We hope to eventually share some of what the Lord allowed us to go through to highlight the need and the opportunity for the church in Iran, but right now we will take time to pray and seek the Lord for His will,” said Rostampour, according to Elam’s press statement.

Iran’s Constitution gives Christians “protected” religious minority status, but in practice they face substantial societal discrimination, according to the U.S. Department of State’s International Religious Freedom Report 2009.

An article mandating death for apostates in accordance with sharia (Islamic law) reportedly has been stricken from a draft penal code, but experts on Iran say The Council of Guardians and Iran’s Supreme Leader still have the final say on who receives capital punishment for leaving Islam.

Report from Compass Direct News

‘Pinpricks’ of Truth Making Way into North Korea

Citizens increasingly enlightened about world’s worst violator of religious freedom.

DUBLIN, April 26 (CDN) — As refugees from North Korea and activists from Non-Governmental Organizations (NGOs) gather in Seoul, South Korea this week to highlight human rights violations in the hermit kingdom, there are signs that North Korean citizens are accessing more truth than was previously thought.

A recent survey by the Peterson Institute found that a startling 60 percent of North Koreans now have access to information outside of government propaganda.

“North Koreans are increasingly finding out that their misery is a direct result of the Kim Jong-Il regime, not South Korea and America as we were brainwashed from birth to believe,” Kim Seung Min of Free North Korea Radio said in a press statement. The radio station is a partner in the North Korea Freedom Coalition (NKFC), which is holding its annual North Korea Freedom Week (NKFW) in Seoul rather than Washington, D.C. for the first time in the seven-year history of the event.

“We set out to double the radio listenership of 8 or 9 percent, and we’ve seen a dramatic increase in the number of people who have access to information,” said NKFC Co-Chair Suzanne Scholte. She described the flow of information as “pinpricks in a dark veil over North Korea. Now those pinpricks are becoming huge holes.”

The radio station now air-drops radios into North Korea and broadcasts into the country for five hours a day, adding to information gleaned by refugees and merchants who cross the border regularly to buy Chinese goods.

In recent years the government has been forced to allow a limited market economy, but trade has brought with it illegal technology such as VCR machines, televisions, radios and cell phones that can detect signals from across the border. Previously all televisions and radios available in North Korea could only receive official frequencies. 

“The government hasn’t been able to stamp out the markets, so they begrudgingly allow them to continue,” Scholte confirmed. “This means North Koreans aren’t relying solely on the regime anymore.”

Holding the annual event in Seoul this year sends a significant message, Scholte told Compass.

“This is a spiritual conflict as well as a physical one – some people didn’t want us to call it freedom week,” she said. “But we’re making a statement … God gives us freedom by the very nature of being human and North Koreans are entitled to that too.”

All people say they would never allow the World War II holocaust to be repeated, Scholte said, “but this is a holocaust, a genocide. I firmly believe we will be judged if we fail to intervene.”

The coalition hopes this week’s event will empower the 17,000 strong North Korean defectors in South Korea, awaken the consciousness of the world about human rights conditions in North Korea, and inform all who are suffering in North Korea that others will “work together until the day their freedom, human rights and dignity are realized,” Scholte said in the press statement.

As part of the week’s activities, the coalition will send leaflets into North Korea via balloon stating in part, “In the same year the Universal Declaration of Human Rights was passed, Kim Il-Sung was ensuring that you wouldn’t have any of those rights.”

Religious freedom in particular is almost non-existent. The only accepted belief is Juche – an ideology that strictly enforces worship of the country’s leaders.

“The regime is a perversion of Christianity,” Scholte told Compass. Juche has a holy trinity just as Christianity does, with Father Kim Il-Sung, son Kim Jong-Il, and the spirit of Juche said to give strength to the people.

“Kim Il-Sung is God; a real God can’t replace him,” a former North Korean security agent confirmed in David Hawke’s 2005 report, “A Prison Without Bars.”

While four churches exist in the capital, Pyongyang, experts believe these are largely showpieces for foreign visitors.

The government has allowed token visits from high-profile foreign Christians such as Franklin Graham, president of the Billy Graham Evangelistic Association, who preached at Bongsu Protestant church in Pyongyang in August 2008; and two U.S. Christian bands, Casting Crowns and Annie Moses, attended and won awards at the Spring Friendship Arts Festival in April 2009.

Worship outside limited official venues is simply not tolerated, giving North Korea first place on Christian support organization Open Doors’ 2010 World Watch List for persecution of Christians.

Ordinary citizens caught with a Bible or in a clandestine prayer meeting are immediately labeled members of the hostile class and either executed or placed in prison labor camps, along with three generations of their immediate family. Every North Korean belongs to either the “hostile,” “wavering” or “core” class, affecting privileges from food and housing to education and physical freedom, according to Hawke’s report.

There are no churches outside the capital, but the regime in 2001 estimated there were 12,000 Protestants and 800 Catholics in North Korea. In July 2002 the government also reported the existence of 500 vaguely-defined “family worship centers” catering to a population of approximately 22.7 million, according to a September 2009 International Religious Freedom report issued by the U.S. State Department.

By contrast, South Korea’s Dong-A Ilbo newspaper in July 2009 put the estimate at 30,000 Christians, some NGOs and academics estimate there may be up to several hundred thousand underground Christians.

Uncertain Future

As North Korea celebrated the birthday of Kim Jong-Il on Feb. 16, rumors spread that the elderly leader, currently battling heart problems, had chosen third son Kim Jong-Eun as his successor.

Documents extolling the virtues of Kim Jong-Eun began circulating as early as November, according to the Daily NK online news agency. An official “education” campaign for elite officials began in January and was extended to lesser officials in March. One document obtained by the agency described the “Youth Captain” as being “the embodiment of Kim Il-Sung’s appearance and ideology.”

“Kim picked this son because he’s ruthless and evil,” Scholte said, “but I don’t think they’re quite ready to hand over to him yet. There is an uncertainty, a vulnerability.”

Scholte believes this is the ideal time to “reach out, get information in there and push every possible way.”

“There are many double-thinkers among the elite,” she explained. “They know the regime is wrong, but they have the Mercedes, the education for their kids and so on, so they have no incentive to leave.”

The coalition is trying to persuade South Korea to establish a criminal tribunal, she said.

“North Koreans are actually citizens of South Korea by law,” she said. “We have to let these guys know there’s going to be a reckoning, to create a good reason for them not to cooperate [with authorities].”

Those in other countries have an obligation too, Scholte concluded. “When people walk out of the camps, it will haunt us. They’ll want to know, ‘What were you doing?’ We will be held accountable.”

Article 26 of North Korea’s constitution declares that the people have freedom of religion. The organizers of this year’s freedom week fervently hope that this declaration will soon become a reality.

SIDEBAR

The Cross at the Border: China’s Complicity in Refugees’ Suffering

Non-Governmental Organizations (NGOs) estimate anywhere from 30,000 to 250,000 refugees from North Korea are living in China, either in border areas or deeper inland. Few are Christians when they emerge from North Korea, but the whispered advice among refugees is to “head for a cross,” signaling a Chinese church that may assist them, according to a February 2009 National Geographic report.

Since China will not allow the United Nations High Commissioner for Refugees access to border areas, Chinese Christians work with Christian NGOs to provide an “underground railroad” moving refugees via several routes to safety, most often in South Korea.

Chun Ki-Won, director of Christian NGO Durihana, admits that some of the refugees adopt Christianity to win favor with their rescuers, but others retain and strengthen their faith on arrival in South Korea.

China insists that the refugees are economic migrants and pays police a bounty to arrest and return them to North Korea. On arrival, North Korean officials pointedly question the refugees about contact with Chinese Christians or Christian NGOs. If any contact is admitted, execution or imprisonment is likely, according to David Hawke’s 2005 report, “A Prison Without Bars.”

As one refugee told Hawke, “Having faith in God is an act of espionage.”

Still others choose to return to North Korea with Bibles and other Christian resources at great risk to themselves. For example, officials in June 2009 publicly executed Ri Hyon-Ok, caught distributing Bibles in Ryongchon, a city near the Chinese border, South Korean activists reported.

China remains impervious to the refugees’ plight.

“China fears being flooded by refugees if they show compassion,” said Suzanne Scholte, co-chair of the North Korea Freedom Coalition. “But refugee flows aren’t going to collapse the [North Korean] regime. If that was going to happen, it would have happened already during the famine, so their argument doesn’t hold water.”

She added that North Koreans don’t want to leave. “They leave because of Kim Jong-Il,” she said. “Those [North Korean refugees] in South Korea want to go back and take freedom with them.”

Two U.S. Christians entered North Korea in recent months with the same goal in mind. Robert Park, an evangelical Christian missionary, crossed the border on Dec. 25 with a letter calling for Kim Jong-Il to resign.

Officials immediately arrested Park, according to the regime’s Korean Central News Agency. He was later sentenced to eight years of hard labor but released in late February after making what many experts believe was a forced confession.

Fellow activist Aijalon Mahli Gomes entered North Korea on Jan. 25, the same news agency reported. Officials sentenced Gomes to nine years of hard labor and fined him 70 million new Won (US$518,520). At press time Gomes remained in detention.

Report from Compass Direct News