The heavily mutated Omicron variant has sparked concerns that it may evade the protection of vaccines – but there have also been suggestions the new version of the coronavirus may be less virulent.
Scientists currently have little data to go on, so hopes the new variant is not as likely to cause serious illness rests largely on reports from doctors in South Africa who treated early Omicron cases.
It will probably be weeks before researchers fully understand Omicron’s pathogenicity, transmissibility and ability to cause illness, even in vaccinated people.
But if it does represent a more mild form of the coronavirus, it could mean that the pandemic follows a pattern seen elsewhere, in which infections become endemic but less severe over time.
“If you think about the extremes, a virus that kills 90 percent of the people it infected would very quickly run out of people. It won’t have anywhere to go,” said Prof Ian Jones, a virologist at the University of Reading in the UK.
“On the other hand, a virus that you hardly notice you have, but was transmitted easily, would be transmitted over time. The tendency is for viruses to lose virulence and cause less severe disease. They become endemic.”
The idea that pathogens tend to become milder as time goes on, sometimes called the law of declining virulence, is often attributed to Theobald Smith, a celebrated American research scientist of the 19th and 20th centuries.
According to the theory, viruses spread more effectively if they replicate quickly but do not cause severe disease, at least in the early stages of infection. This is because if the hosts remain well, they can mix with others and spread the pathogen.
Several disease outbreaks appear to tie in with Mr Smith’s theory.
Among those often quoted are the “Spanish flu” pandemic of 1918, which is thought to have killed tens of millions of people around the globe. Some have suggested the virus gradually became less dangerous as the pandemic continued into 1920, when it ended.
Another example concerns a coronavirus that infects people, OC43. This may have caused the “Russian flu” pandemic of the late 19th century, which is blamed for at least one million deaths. Today, OC43 is much less deadly, as it is one of several viruses that causes the common cold.
While Mr Smith’s idea gained wide acceptance, in recent decades researchers have put forward other models that suggest a more varied range of scenarios, in which evolution towards reduced pathogenicity is not inevitable.
Among the ideas is that if pathogens are durable outside their host, they may be successful when they are both highly transmissible and virulent. Durability allows them to survive outside of their host for extended periods before finding a new host.
The myxoma virus, the cause of myxomatosis in rabbits, while often cited as a case where virulence has declined over time, may actually represent a more mixed picture.
Introduced to Australia, France and the UK in the 1950s, it initially caused devastation among rabbit populations, although as time continued, more rabbits survived infection.
This has been put down to both reduced virulence from the virus and increased resistance in the rabbit populations.
Researchers at the University of Oxford who published a study in 2019 tracing the evolution of rabbits in relation to myxomatosis noted, however, that more virulent strains of the virus have emerged in recent times. There is, they said, an ongoing “arms race” between the virus and the rabbit population.
Evidence so far with the coronavirus has suggested to some scientists that it is not becoming less harmful.
For example, as well as being highly transmissible, the Delta variant has been associated with a higher rate of hospital admissions (and transmissibility) than the Alpha variant, which emerged earlier.
Because the coronavirus spreads most readily in the early stages of disease, before severe symptoms develop, there may be little evolutionary pressure for it to become less virulent. Even if people subsequently fall severely ill and even die, the hypothesis suggests, the virus will already have spread.
According to Dr Andrew Freedman, an infectious diseases specialist at Cardiff University, in terms of evolution “it’s not inevitable” that the coronavirus will cause milder infections as time goes on.
“Mutations can make it more transmissible and virulent in the worst-case scenario,” he said.
If the coronavirus becomes endemic and milder over time, vaccination and natural infection (which confers immunity) are, he said, likely to be the key factors.
Prof Jones also emphasised the importance of widespread immunity in ending the pandemic.
“What will happen over time, the edge of the disease will fade further, as long as immunity is maintained,” he said.
In any case, Prof Jones said that, for the moment, it was unclear whether the Omicron variant causes less severe infection.
While doctors in South Africa have highlighted that cases have been mild, “exact data” has yet to be collected.
“Until we see a huge number of infections, I don’t see it’s a realistic assessment, especially in South Africa, where quite a lot of cases are not reported accurately,” he said.
The biog
Name: Greg Heinricks
From: Alberta, western Canada
Record fish: 56kg sailfish
Member of: International Game Fish Association
Company: Arabian Divers and Sportfishing Charters
MATCH INFO
Uefa Champions League semi-final, first leg
Tottenham 0-1 Ajax, Tuesday
Second leg
Ajax v Tottenham, Wednesday, May 8, 11pm
Game is on BeIN Sports
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The five pillars of Islam
Villains
Queens of the Stone Age
Matador
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MOUNTAINHEAD REVIEW
Starring: Ramy Youssef, Steve Carell, Jason Schwartzman
Director: Jesse Armstrong
Rating: 3.5/5
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Zayed Sustainability Prize
Barbie
%3Cp%3E%3Cstrong%3EDirector%3A%3C%2Fstrong%3E%20Greta%20Gerwig%3Cbr%3E%3Cstrong%3EStars%3A%3C%2Fstrong%3E%20Margot%20Robbie%2C%20Ryan%20Gosling%2C%20Will%20Ferrell%2C%20America%20Ferrera%3Cbr%3E%3Cstrong%3ERating%3A%3C%2Fstrong%3E%204%2F5%3Cbr%3E%3C%2Fp%3E%0A
Zayed Sustainability Prize
Key facilities
- Olympic-size swimming pool with a split bulkhead for multi-use configurations, including water polo and 50m/25m training lanes
- Premier League-standard football pitch
- 400m Olympic running track
- NBA-spec basketball court with auditorium
- 600-seat auditorium
- Spaces for historical and cultural exploration
- An elevated football field that doubles as a helipad
- Specialist robotics and science laboratories
- AR and VR-enabled learning centres
- Disruption Lab and Research Centre for developing entrepreneurial skills
Scoreline
Australia 2-1 Thailand
Australia: Juric 69', Leckie 86'
Thailand: Pokklaw 82'
Zayed Sustainability Prize
Mohammed bin Zayed Majlis
The years Ramadan fell in May
Killing of Qassem Suleimani
Al Jazira's foreign quartet for 2017/18
Romarinho, Brazil
Lassana Diarra, France
Sardor Rashidov, Uzbekistan
Mbark Boussoufa, Morocco
Virtuzone GCC Sixes
Date and venue Friday and Saturday, ICC Academy, Dubai Sports City
Time Matches start at 9am
Groups
A Blighty Ducks, Darjeeling Colts, Darjeeling Social, Dubai Wombats; B Darjeeling Veterans, Kuwait Casuals, Loose Cannons, Savannah Lions; C Awali Taverners, Darjeeling, Dromedary, Darjeeling Good Eggs
Last five meetings
2013: South Korea 0-2 Brazil
2002: South Korea 2-3 Brazil
1999: South Korea 1-0 Brazil
1997: South Korea 1-2 Brazil
1995: South Korea 0-1 Brazil
Note: All friendlies
Singham Again
Director: Rohit Shetty
Stars: Ajay Devgn, Kareena Kapoor Khan, Ranveer Singh, Akshay Kumar, Tiger Shroff, Deepika Padukone
Rating: 3/5
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The five pillars of Islam
Key figures in the life of the fort
Sheikh Dhiyab bin Isa (ruled 1761-1793) Built Qasr Al Hosn as a watchtower to guard over the only freshwater well on Abu Dhabi island.
Sheikh Shakhbut bin Dhiyab (ruled 1793-1816) Expanded the tower into a small fort and transferred his ruling place of residence from Liwa Oasis to the fort on the island.
Sheikh Tahnoon bin Shakhbut (ruled 1818-1833) Expanded Qasr Al Hosn further as Abu Dhabi grew from a small village of palm huts to a town of more than 5,000 inhabitants.
Sheikh Khalifa bin Shakhbut (ruled 1833-1845) Repaired and fortified the fort.
Sheikh Saeed bin Tahnoon (ruled 1845-1855) Turned Qasr Al Hosn into a strong two-storied structure.
Sheikh Zayed bin Khalifa (ruled 1855-1909) Expanded Qasr Al Hosn further to reflect the emirate's increasing prominence.
Sheikh Shakhbut bin Sultan (ruled 1928-1966) Renovated and enlarged Qasr Al Hosn, adding a decorative arch and two new villas.
Sheikh Zayed bin Sultan (ruled 1966-2004) Moved the royal residence to Al Manhal palace and kept his diwan at Qasr Al Hosn.
Sources: Jayanti Maitra, www.adach.ae
Mohammed bin Zayed Majlis
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Scorecard:
England 458 & 119/1 (51.0 ov)
South Africa 361
England lead by 216 runs with 9 wickets remaining
Killing of Qassem Suleimani
Killing of Qassem Suleimani
Killing of Qassem Suleimani
Defence review at a glance
• Increase defence spending to 2.5% of GDP by 2027 but given “turbulent times it may be necessary to go faster”
• Prioritise a shift towards working with AI and autonomous systems
• Invest in the resilience of military space systems.
• Number of active reserves should be increased by 20%
• More F-35 fighter jets required in the next decade
• New “hybrid Navy” with AUKUS submarines and autonomous vessels
The years Ramadan fell in May
DEADPOOL & WOLVERINE
Starring: Ryan Reynolds, Hugh Jackman, Emma Corrin
Director: Shawn Levy
Rating: 3/5
COMPANY%20PROFILE
%3Cp%3E%3Cstrong%3EName%3A%20%3C%2Fstrong%3ESmartCrowd%0D%3Cbr%3E%3Cstrong%3EStarted%3A%20%3C%2Fstrong%3E2018%0D%3Cbr%3E%3Cstrong%3EFounder%3A%20%3C%2Fstrong%3ESiddiq%20Farid%20and%20Musfique%20Ahmed%0D%3Cbr%3E%3Cstrong%3EBased%3A%20%3C%2Fstrong%3EDubai%0D%3Cbr%3E%3Cstrong%3ESector%3A%20%3C%2Fstrong%3EFinTech%20%2F%20PropTech%0D%3Cbr%3E%3Cstrong%3EInitial%20investment%3A%20%3C%2Fstrong%3E%24650%2C000%0D%3Cbr%3E%3Cstrong%3ECurrent%20number%20of%20staff%3A%3C%2Fstrong%3E%2035%0D%3Cbr%3E%3Cstrong%3EInvestment%20stage%3A%20%3C%2Fstrong%3ESeries%20A%0D%3Cbr%3E%3Cstrong%3EInvestors%3A%20%3C%2Fstrong%3EVarious%20institutional%20investors%20and%20notable%20angel%20investors%20(500%20MENA%2C%20Shurooq%2C%20Mada%2C%20Seedstar%2C%20Tricap)%3C%2Fp%3E%0A
Yemen's Bahais and the charges they often face
The Baha'i faith was made known in Yemen in the 19th century, first introduced by an Iranian man named Ali Muhammad Al Shirazi, considered the Herald of the Baha'i faith in 1844.
The Baha'i faith has had a growing number of followers in recent years despite persecution in Yemen and Iran.
Today, some 2,000 Baha'is reside in Yemen, according to Insaf.
"The 24 defendants represented by the House of Justice, which has intelligence outfits from the uS and the UK working to carry out an espionage scheme in Yemen under the guise of religion.. aimed to impant and found the Bahai sect on Yemeni soil by bringing foreign Bahais from abroad and homing them in Yemen," the charge sheet said.
Baha'Ullah, the founder of the Bahai faith, was exiled by the Ottoman Empire in 1868 from Iran to what is now Israel. Now, the Bahai faith's highest governing body, known as the Universal House of Justice, is based in the Israeli city of Haifa, which the Bahais turn towards during prayer.
The Houthis cite this as collective "evidence" of Bahai "links" to Israel - which the Houthis consider their enemy.
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Mohammed bin Zayed Majlis
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More coverage from the Future Forum
The burning issue
The internal combustion engine is facing a watershed moment – major manufacturer Volvo is to stop producing petroleum-powered vehicles by 2021 and countries in Europe, including the UK, have vowed to ban their sale before 2040. The National takes a look at the story of one of the most successful technologies of the last 100 years and how it has impacted life in the UAE.
Read part four: an affection for classic cars lives on
Read part three: the age of the electric vehicle begins
Read part one: how cars came to the UAE
Dubai Women's Tour teams
Agolico BMC
Andy Schleck Cycles-Immo Losch
Aromitalia Basso Bikes Vaiano
Cogeas Mettler Look
Doltcini-Van Eyck Sport
Hitec Products – Birk Sport
Kazakhstan National Team
Kuwait Cycling Team
Macogep Tornatech Girondins de Bordeaux
Minsk Cycling Club
Pannonia Regional Team (Fehérvár)
Team Auvergne-Rhône-Alpes
Team Ciclotel
UAE Women’s Team
Under 23 Kazakhstan Team
Wheel Divas Cycling Team
Abaya trends
The utilitarian robe held dear by Arab women is undergoing a change that reveals it as an elegant and graceful garment available in a range of colours and fabrics, while retaining its traditional appeal.
UAE currency: the story behind the money in your pockets
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THE BIO:
Favourite holiday destination: Thailand. I go every year and I’m obsessed with the fitness camps there.
Favourite book: Born to Run by Christopher McDougall. It’s an amazing story about barefoot running.
Favourite film: A League of their Own. I used to love watching it in my granny’s house when I was seven.
Personal motto: Believe it and you can achieve it.
Our legal columnist
Name: Yousef Al Bahar
Advocate at Al Bahar & Associate Advocates and Legal Consultants, established in 1994
Education: Mr Al Bahar was born in 1979 and graduated in 2008 from the Judicial Institute. He took after his father, who was one of the first Emirati lawyers
Palestine and Israel - live updates
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The Bio
Favourite vegetable: “I really like the taste of the beetroot, the potatoes and the eggplant we are producing.”
Holiday destination: “I like Paris very much, it’s a city very close to my heart.”
Book: “Das Kapital, by Karl Marx. I am not a communist, but there are a lot of lessons for the capitalist system, if you let it get out of control, and humanity.”
Musician: “I like very much Fairuz, the Lebanese singer, and the other is Umm Kulthum. Fairuz is for listening to in the morning, Umm Kulthum for the night.”