Saudi Press

Saudi Arabia and the world
Saturday, Jun 21, 2025

COVID-19 Infection Gives Some Immunity, But Virus Can Still Be Spread, Study Finds

COVID-19 Infection Gives Some Immunity, But Virus Can Still Be Spread, Study Finds

But experts cautioned that the findings mean people who contracted the disease in the first wave of the pandemic in the early months of 2020 may now be vulnerable to catching it again.

People who have had COVID-19 are highly likely to have immunity to it for at least five months, but there is evidence that those with antibodies may still be able to carry and spread the virus, a study of British healthcare workers has found.

Preliminary findings by scientists at Public Health England (PHE) showed that reinfections in people who have COVID-19 antibodies from a past infection are rare - with only 44 cases found among 6,614 previously infected people in the study.

But experts cautioned that the findings mean people who contracted the disease in the first wave of the pandemic in the early months of 2020 may now be vulnerable to catching it again.

They also warned that people with so-called natural immunity - acquired through having had the infection - may still be able carry the SARS-CoV-2 coronavirus in their nose and throat and could unwittingly pass it on.

"We now know that most of those who have had the virus, and developed antibodies, are protected from reinfection, but this is not total and we do not yet know how long protection lasts," said Susan Hopkins, senior medical adviser at PHE and co-leader of the study, whose findings were published on Thursday.

"This means even if you believe you already had the disease and are protected, you can be reassured it is highly unlikely you will develop severe infections. But there is still a risk you could acquire an infection and transmit (it) to others."

Major Implications


Experts not directly involved in the research, which is known as the SIREN study, urged people to note its key findings.

"These data reinforce the message that, for the time being, everyone is a potential source of infection for others and should behave accordingly," said Eleanor Riley, a professor of immunology and infectious disease at Edinburgh University.

Simon Clarke, an associate professor in cellular microbiology at Reading University, said the study "has major implications for how we can get out of the current crisis".

"This means that the vast majority of the population will either need to have natural immunity or have been immunised for us to fully lift restrictions on our lives, unless we are prepared to see many more people being infected and dying from COVID-19," he said.

PHE said in a statement that the study had not been able to explore antibody or other immune responses to the COVID-19 vaccines being rolled out in Britain. Vaccine effects would be studied as part of SIREN later this year, it said.

The SIREN study involves tens of thousands of healthcare workers in Britain who have been tested regularly since June for new COVID-19 infections as well as for the presence of antibodies.

Between June 18 and Nov. 24, scientists found 44 potential reinfections - two "probable" and 42 "possible" - among 6,614 participants who had tested positive for antibodies. This represents an 83% rate of protection from reinfection, they said.

The researchers said they would continue to follow the participants to see if this natural immunity might last longer than five months in some. But they said early evidence from the next stage of the study suggested some people with immunity could still carry high levels of virus.

Newsletter

Related Articles

Saudi Press
0:00
0:00
Close
Israel Confirms Assassination of Quds Force Commander in Tehran
16 Billion Login Credentials Leaked in Unprecedented Cybersecurity Breach
Senate hearing on who was 'really running' Biden White House kicks off
G7 Leaders Fail to Reach Consensus on Key Global Issues
Mass exodus in Tehran as millions try to flee following Trump’s evacuation order
Iranian Military Officers Reportedly Seek Contact with Reza Pahlavi, Signal Intent to Defect
Vietnam Emerges as Luxury Yacht Destination for Ultra‑Rich
China's Iranian Oil Imports Face Disruption Amid Escalating Middle East Tensions
Trump Demands Iran's Unconditional Surrender Amid Escalating Conflict
Israeli Airstrike Targets Iranian State TV in Central Tehran
President Trump is leaving the G7 summit early and has ordered the National Security Council to the Situation Room
Netanyahu Signals Potential Regime Change in Iran
Analysts Warn Iran May Resort to Unconventional Warfare
Iranian Regime Faces Existential Threat Amid Conflict
Energy Infrastructure Becomes War Zone in Middle East
Iran Conducts Ballistic Missile Launches Amid Heightened Tensions with Israel
Iran Signals Openness to Nuclear Negotiations Amid Ongoing Regional Tensions
Shock Within Iran’s Leadership: Khamenei’s Failed Plan to Launch 1,000 Missiles Against Israel
Trump's Anti-War Stance Tested Amid Israel-Iran Conflict
UK Deploys Jets to Middle East Amid Rising Tensions
Exiled Iranian Prince Reza Pahlavi Urges Overthrow of Khamenei Regime
Wreck of $17 Billion San José Galleon Identified Off Colombia After 300 Years
Iran Launches Extensive Missile Attack on Israel Following Israeli Strikes on Nuclear Sites
Israel Issues Ultimatum to Iran Over Potential Retaliation and Nuclear Facilities
Black Box Recovered from Air India Crash Site
Coinbase CEO Warns Bitcoin Could Supplant US Dollar Amid Mounting National Debt
Trump to Iran: Make a Deal — Sign or Die
Operation "Like a Lion": Israel Strikes Iran in Unprecedented Offensive
Israel Launches 'Operation Rising Lion' Targeting Iranian Nuclear and Military Sites
Israeli Forces Intercept Gaza-Bound Aid Vessel Carrying Greta Thunberg
IMF Warns of Severe Global Trade War Impacts on Emerging Markets
Syria to Reconnect to Global Economy After 14 Years of Isolation
Israel Confirms Arming Gaza Clan to Counter Hamas Influence
Global News Roundup: From Ukraine's strategic military strikes and Russia's demands and Tensions Escalate in Ukraine, to serious legal issues faced by Britons in Bali and Trump's media criticism, the latest developments highlight a turbulent landscape
U.S. Reduces Military Presence in Syria
Trump Demands Iran End All Uranium Enrichment in Nuclear Talks
Iran Warns Europe Against Politicizing UN Nuclear Report
Paris Saint-Germain's Greatest Triumph Is Football’s Lowest Point
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
×