Here is why vaccinated people still need to wear mask

News Network
December 9, 2020

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Dec 9: The new Covid-19 vaccines from Pfizer and Moderna seem to be remarkably good at preventing serious illness. But it’s unclear how well they will curb the spread of the coronavirus.

That’s because the Pfizer and Moderna trials tracked only how many vaccinated people became sick with Covid-19. That leaves open the possibility that some vaccinated people get infected without developing symptoms and could then silently transmit the virus — especially if they come in close contact with others or stop wearing masks.

If vaccinated people are silent spreaders of the virus, they may keep it circulating in their communities, putting unvaccinated people at risk.

“A lot of people are thinking that once they get vaccinated, they’re not going to have to wear masks anymore,” said Michal Tal, an immunologist at Stanford University. “It’s really going to be critical for them to know if they have to keep wearing masks because they could still be contagious.”

In most respiratory infections, including the new coronavirus, the nose is the main port of entry. The virus rapidly multiplies there, jolting the immune system to produce a type of antibodies that are specific to the mucosa, the moist tissue lining the nose, mouth, lungs and stomach. If the same person is exposed to the virus a second time, those antibodies, as well as immune cells that remember the virus, rapidly shut down the virus in the nose before it gets a chance to take hold elsewhere in the body.

The coronavirus vaccines, in contrast, are injected deep into the muscles and quickly absorbed into the blood, where they stimulate the immune system to produce antibodies. This appears to be enough protection to keep the vaccinated person from getting ill.

Some of those antibodies will circulate to the nasal mucosa and stand guard there, but it’s not clear how much of the antibody pool can be mobilized or how quickly. If the answer is not much, then viruses could bloom in the nose — and be sneezed or breathed out to infect others.

“It’s a race: It depends whether the virus can replicate faster, or the immune system can control it faster,” said Marion Pepper, an immunologist at the University of Washington in Seattle. “It’s a really important question.”

This is why mucosal vaccines, like nasal spray FluMist or the oral polio vaccine, are better than intramuscular injections at fending off respiratory viruses, experts said.

The next generation of coronavirus vaccines may elicit immunity in the nose and the rest of the respiratory tract, where it’s most needed. Or people could get an intramuscular injection followed by a mucosal boost that produces protective antibodies in the nose and throat.

The coronavirus vaccines have proved to be powerful shields against severe illness, but that is no guarantee of their efficacy in the nose. The lungs — the site of severe symptoms — are much more accessible to the circulating antibodies than the nose or throat, making them easier to safeguard.

“Preventing severe disease is easiest, preventing mild disease is harder, and preventing all infections is the hardest,” said Deepta Bhattacharya, an immunologist at the University of Arizona. “If it’s 95% effective at preventing symptomatic disease, it’s going to be something less than that in preventing all infections, for sure.”

Still, he and other experts said they were optimistic that the vaccines would suppress the virus enough even in the nose and throat to prevent immunized people from spreading it to others.

“My feeling is that once you develop some form of immunity with the vaccine, your ability to get infected will also go down,” said Akiko Iwasaki, an immunologist at Yale University. “Even if you’re infected, the level of virus that you replicate in your nose should be reduced.”

The vaccine trials have not produced data on how many vaccinated people were infected with the virus but did not have symptoms. Some hints are emerging, however.

AstraZeneca, which announced some of its trial results in November, said that volunteers had been testing themselves regularly for the virus and that those results suggested that the vaccine might prevent some infections.

Pfizer will test a subset of its trial participants for antibodies against a viral protein called N. Because the vaccines have nothing to do with this protein, N antibodies would reveal whether the volunteers had become infected with the virus after immunization, said Jerica Pitts, a spokeswoman for the company.

Moderna also plans to analyze blood from all its participants and test for N antibodies.

“It will take several weeks before we can expect to see those results,” said Colleen Hussey, a spokeswoman for Moderna.

The trials have so far analyzed only blood, but testing for antibodies in mucosa would confirm that the antibodies can travel to the nose and mouth. Tal’s team is planning to analyze matched blood and saliva samples from volunteers in the Johnson & Johnson trial to see how the two antibody levels compare.

In the meantime, Bhattacharya said, he was encouraged by recent work showing that people who received an intramuscular flu vaccine had abundant antibodies in the nose. And a study of Covid-19 patients found that antibody levels in saliva and blood were closely matched — suggesting that a strong immune response in the blood would also protect mucosal tissues.

Only people who have virus teeming in their nose and throat would be expected to transmit the virus, and the lack of symptoms in the immunized people who became infected suggests that the vaccine may have kept the virus levels in check.

But some studies have suggested that even people with no symptoms can have high amounts of coronavirus in their nose, noted Dr. Yvonne Maldonado, who represents the American Academy of Pediatrics at meetings of the Federal Advisory Committee on Immunization Practices. The first person confirmed to be reinfected with the coronavirus, a 33-year-old man in Hong Kong, also did not have symptoms but harboured enough virus to infect others.

Vaccinated people who have a high viral load but don’t have symptoms “would actually be, in some ways, even worse spreaders because they may be under a false sense of security,” Maldonado said.

Tal said she was concerned by monkey studies showing that some vaccinated animals did not get ill but still had virus in their nose.

But those monkeys were intentionally exposed to massive amounts of virus and still had less virus than unvaccinated animals, said John Moore, a virus expert at Weill Cornell Medicine in New York.

“The more you reduce viral load, the less likely you are to be transmissible,” Moore said. But “all of these are things where data trumps theory, and we need the data.”

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News Network
April 7,2025

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Rafah, a city along the border of the Gaza Strip and Egypt, has entirely been “wiped off the map” by Israel’s brutal campaign of genocide and ethnic cleansing, says the Gaza government media office.

The media office said Sunday in a statement on X that the southern city of Gaza has entirely been demolished to make way for Israel to turn it into a “closed military operations zone."

The statement said Israel’s military forces have been carrying out “horrific massacres against defenseless civilians” in Rafah, creating a “full-fledged humanitarian disaster.”

According to the officials, Israeli forces have destroyed over 90% of homes—more than 20,000 buildings in Rafah.

All of the historical buildings, archaeological sites, museums, modern homes, the civilian infrastructure, the shops, cafes, restaurants, hospitals, schools, and universities have been demolished.

The officials said the regime's forces have also demolished 22 of 24 water wells, including a large water treatment plant and facility that was built 25 years ago by the Canadian government.

“Tens of thousands of families” are now without safe drinking water, and over 85% of the sewage system has been destroyed, raising fears of disease outbreaks, said the statement.

At least 12 medical centers are out of service, including Abu Yousef al-Najjar Hospital, which was reportedly blown up by an explosive robot.

Rafah is “uninhabitable,” now, the media office said.

The Israeli military’s goal, it said, is to “empty the land of its people and alter its geographic and demographic features.”

Rafah, a city that was built over 3,300 years ago, had a population of 171,889. As recently as February, 1.4 million Palestinians took shelter there as a result of Israel’s forced displacement of the population in northern parts of the besieged enclave.

The city, which was once designated as a "safe zone" by Israel's military, has now been reduced to rubble. The regime's military has now seized the ruins of Rafah and ordered every survivor out, to expand its "security buffer zone" along Gaza's borders.

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Agencies
March 26,2025

The airstrikes led by the United States have killed at least 25 civilians in Yemen over the past week, marking the deadliest week of bombing on the country since the final months of the Washington-backed Saudi war in January 2022.

In a report released on Tuesday, the Yemen Data Project said the 25 civilians were the victims of 38 US-led aerial assaults on March 15-21, adding that 28 people were also injured in the attacks.

The independent tracker also said that 21 out of the 38 US air raids hit non-military, civilian targets.

“Civilian targets hit included: a medical storage facility, a medical center, a school, a wedding hall, residential areas, a cotton gin facility, a health office, Bedouin tents, and Al-Eiman University,” it said.

The deadliest US strike in the first week of US bombing campaign struck a residential area in Yemen’s northwestern Sa'ada province, killing 10 civilians and wounding 11 others, among them children.

The US began bombing Yemen on March 15, a few days after Yemen resumed its operation against Israeli-linked ships in response to Israel’s Gaza aid blockade that violated a ceasefire with the Hamas resistance group.

The Yemeni Armed Forces began their anti-Israel naval campaign in November 2023, a month after the occupying regime waged a genocidal war on the Gaza Strip.

The Yemeni forces halted their attacks in solidarity with the Palestinians in January, when Israel accepted a three-phase Gaza ceasefire.

Two months later, however, Israel unilaterally broke the Gaza truce and resumed its brutal onslaught on the besieged territory.

On Tuesday, Yemeni media reported 17 US strikes on Sa'ada and two more on the nearby 'Amran province.

The reports said American warplanes carried out "aggressive air raids... causing material damage to citizens' property," but gave no details of casualties.

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Agencies
March 28,2025

Udupi: Deputy Commissioner K. Vidya Kumari has directed officials to expedite land acquisition for designated industrial zones in the district to facilitate new industries. She issued these instructions during a meeting at Rajatadri on Wednesday.

Lands have been identified across various taluks for industrial development. The DC emphasized that KIADB must acquire these lands and ensure essential infrastructure—electricity, roads, and drainage—to attract industries and generate employment.

A total of 77 acres of private land has been acquired and compensated, including 31.2 acres in Kerebettu village, Hebri taluk, and 45.7 acres in Shivapura village. However, approval for 36.5 acres of government land is still pending. She instructed the forest department to assess whether this land falls under an eco-sensitive zone.

For the Belapu Industrial Area, the DC urged officials to accelerate minor land acquisitions for road expansion and commence construction at the earliest. She also mandated rainwater harvesting systems for all units in the Miyaru Industrial Area to tackle water scarcity.

Currently, 22 export-based units operate in the district. The DC encouraged further promotion of exports and an increase in their number.

The meeting was attended by Joint Director of Industries Nagraj V. Naik, KIADB Development Officer Srinivasa Murthy, Small-Scale Industries Association District President Harish Kunder, Deputy Director of the District Industrial Center Seetharam Shetty, District Skill Development Officer Arun B., and others.

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