Saudi Press

Saudi Arabia and the world
Sunday, Jun 01, 2025

Delta dominates the world, but scientists watch for worrisome offspring

Delta dominates the world, but scientists watch for worrisome offspring

The Delta variant of the SARS-CoV-2 virus now accounts for nearly all of the coronavirus infections globally, fueled by unchecked spread of the novel coronavirus in many parts of the world. So far, vaccines are still able to defend against serious disease and death from Delta, but scientists remain on alert.

Here is what we know:

DELTA - STILL DOMINANT


The Delta variant, first detected in India in December 2020, remains the most worrisome version of the SARS-CoV-2 virus.

The World Health Organization classifies Delta as a variant of concern, a category that means the variant is capable of increasing transmissibility, causing more severe disease or reducing the benefit of vaccines and treatments.

Delta's "superpower" is its transmissibility, according to Shane Crotty, a virologist at the La Jolla Institute for Immunology in San Diego.

Delta is more than two times as contagious as previous SARS-CoV-2 variants, according to the U.S. Centers for Disease Control and Prevention. Studies suggest it may be more likely to put infected people in the hospital than prior forms of the virus.

Delta also can cause symptoms two to three days sooner than the original coronavirus, giving the immune system less time to mount a defense.

People infected with Delta carry around 1,200 times more virus in their noses compared with the original version of the coronavirus. The amount of virus in vaccinated individuals who become infected with Delta is on par with those who are unvaccinated, and both can transmit the virus to others.

In vaccinated people, however, the amount of virus drops more quickly, so they likely spread the virus for a shorter time.

According to the WHO, Delta makes up 99.5% of all genomic sequences reported to public databases and has "outcompeted" other variants in most countries.

A key exception is South America, where Delta has spread more gradually, and other variants previously seen as possible global threats - notably Gamma, Lambda and Mu - still contribute to a significant proportion of reported cases.

DELTA OFFSPRING


Given Delta's global dominance, many vaccine experts now believe that all future variants will be offshoots of Delta.

One notable Delta "grandchild" is known as AY.4.2 and is concentrated largely in the UK, where it makes up roughly 10% of sequenced virus samples.

AY.4.2 carries two additional mutations in the spike protein, which the virus uses to enter cells. Scientists are still studying what advantage, if any, these mutations confer.

The UK Health Security Agency has designated the AY.4.2 a "Variant Under Investigation." A preliminary analysis suggests it does not significantly impair vaccine effectiveness compared with Delta, but there is some evidence that it could be slightly more transmissible, the agency said.

According to the WHO, AY.4.2 has spread to at least 42 countries, including the United States.

MORE ON THE WAY?


Virus experts are closely watching the evolution of Delta, looking for any sign that it has acquired mutations that would allow the highly transmissible variant to pierce the immune protection of vaccines and natural infection.

Even so, while current vaccines prevent severe disease and death, they do not block infection. The virus is still capable of replicating in the nose, even among vaccinated people, who can then transmit the disease through tiny, aerosolized droplets.

To defeat SARS-CoV-2 will likely require a new generation of vaccines that also block transmission, according to Dr. Gregory Poland, a vaccine developer at the Mayo Clinic. Until then, Poland and other experts say, the world remains vulnerable.

Newsletter

Related Articles

Saudi Press
0:00
0:00
Close
OPEC+ Agrees to Increase Oil Output for Third Consecutive Month
Turkey Detains Istanbul Officials Amid Anti-Corruption Crackdown
Meta and Anduril Collaborate on AI-Driven Military Augmented Reality Systems
EU Central Bank Pushes to Replace US Dollar with Euro as World’s Main Currency
European and Arab Ministers Convene in Madrid to Address Gaza Conflict
U.S. Health Secretary Ends Select COVID-19 Vaccine Recommendations
Trump Warns Putin Is 'Playing with Fire' Amid Escalating Ukraine Conflict
India and Pakistan Engage Trump-Linked Lobbyists to Influence U.S. Policy
U.S. Halts New Student Visa Interviews Amid Enhanced Security Measures
Trump Administration Cancels $100 Million in Federal Contracts with Harvard
SpaceX Starship Test Flight Ends in Failure, Mars Mission Timeline Uncertain
King Charles Affirms Canadian Sovereignty Amid U.S. Statehood Pressure
Iranian Revolutionary Guard Founder Warns Against Trusting Regime in Nuclear Talks
UAE Offers Free ChatGPT Plus Subscriptions to Citizens
Lebanon Initiates Plan to Disarm Palestinian Factions
Iran and U.S. Make Limited Progress in Nuclear Talks
The Daily Debate: The Fall of the Dollar — Strategic Reset or Economic Self-Destruction?
Trump Administration's Tariff Policies and Dollar Strategy Spark Global Economic Debate
OpenAI Acquires Jony Ive’s Startup for $6.5 Billion to Build a Revolutionary “Third Core Device”
Turkey Weighs Citizens in Public as Erdoğan Launches National Slimming Campaign
Saudi-Spanish Business Forum Commences in Riyadh
Saudi Arabia and Spain Sign MoU to Boost SME Sectors
UK Suspends Trade Talks with Israel Amid Gaza Offensive
Iran and U.S. Set for Fifth Round of Nuclear Talks Amid Rising Tensions
Russia Expands Military Presence Near Finland Amid Rising Tensions
Indian Scholar Arrested in Crackdown Over Pakistan Conflict Commentary
Israel Eases Gaza Blockade Amid Internal Dispute Over Military Strategy
President Biden’s announcement of advanced prostate cancer sparked public sympathy—but behind closed doors, Democrats are in panic
A Chinese company made solar tiles that look way nicer than regular panels!
Indian jet shootdown: the all-robot legion behind China’s PL-15E missiles
The Chinese Dragon: The True Winner in the India-Pakistan Clash
Australia's Venomous Creatures Contribute to Life-Saving Antivenom Programme
The Spanish Were Right: Long Working Hours Harm Brain Function
Did Former FBI Director Call for Violence Against Trump? Instagram Post Sparks Uproar
US and UAE Partner to Develop Massive AI Data Center Complex
Apple's $95 Million Siri Settlement: Eligible Users Have Until July 2 to File Claims
US and UAE Reach Preliminary Agreement on Nvidia AI Chip Imports
President Trump and Elon Musk Welcomed by Emir of Qatar Sheikh Tamim with Cybertruck Convoy
Strong Warning Issued: Do Not Use General Chatbots for Medical, Legal, or Educational Guidance
Saudi Arabia Emerges as Global Tech Magnet with U.S. Backing and Trump’s Visit
This was President's departure from Saudi Arabia. The Crown Prince personally escorted him back to the airport.
NVIDIA and Saudi Arabia Launch Strategic Partnership to Establish AI Centers
Trump Meets Syrian President Ahmad al-Shara in Historic Encounter
Trump takes a blow torch to the neocons and interventionists while speaking to the Saudis
US and Saudi Arabia Sign Landmark Agreements Across Multiple Sectors
Why Saudi Arabia Rolled Out a Purple Carpet for Donald Trump Instead of Red
Elon Musk Joins Trump Meeting in Saudi Arabia
Trump says it would be 'stupid' not to accept gift of Qatari plane
Quantum Computing Threatens Bitcoin Security
Michael Jordan to Serve as Analyst for NBA Games
×