Scientists Develop New Technique to Deliver Vaccines without Needles

In this May 5, 2022, file photo, a nurse administers the Pfizer booster shot at a COVID-19 vaccination and testing site in Los Angeles. Frederic J. Brown/AFP via Getty Images, FILE
In this May 5, 2022, file photo, a nurse administers the Pfizer booster shot at a COVID-19 vaccination and testing site in Los Angeles. Frederic J. Brown/AFP via Getty Images, FILE
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Scientists Develop New Technique to Deliver Vaccines without Needles

In this May 5, 2022, file photo, a nurse administers the Pfizer booster shot at a COVID-19 vaccination and testing site in Los Angeles. Frederic J. Brown/AFP via Getty Images, FILE
In this May 5, 2022, file photo, a nurse administers the Pfizer booster shot at a COVID-19 vaccination and testing site in Los Angeles. Frederic J. Brown/AFP via Getty Images, FILE

British researchers announced that they have developed a new technique that delivers vaccines in the body without needles. The technique could help deliver vaccines through the skin via ultrasounds without using needles that harm the skin and cause pain. The findings were presented at an international conference in Australia on Monday.

An estimated quarter of adults and two-thirds of children have strong fears around needles, according to the US Centers for Disease Control and Prevention. Yet, public health depends on people being willing to receive vaccines, which are often administered by a jab.

The new method relies on ultrasound pulses to form small bubbles that clear passages through the skin. Then, the pulses deliver the vaccine molecules through the bubbles, which allows its diffusion in the surrounding tissues.

“Our method relies on an acoustic effect called ‘cavitation,’ which is the formation and popping of bubbles in response to a sound wave,” said Darcy Dunn-Lawless, lead author from the University of Oxford’s Institute of Biomedical Engineering.

“We aim to harness the concentrated bursts of mechanical energy produced by these bubble collapses in three main ways. First, to clear passages through the outer layer of dead skin cells and allow vaccine molecules to pass through. Second, to act as a pump that drives the drug molecules into these passages. Lastly, to open up the membranes surrounding the cells themselves, since some types of vaccine must get inside a cell to function,” she explained.

Initial in vivo tests reported that the vaccine molecules delivered by the new approach produced a higher immune response, according to the Eurekalert website.

The researchers theorize this could be due to the immune-rich skin the ultrasonic delivery targets in contrast to the muscles that receive the jab.

According to Lawless, the result is a more efficient vaccine that could help reduce costs and increase efficacy with little risk of side effects. The team plans further research to explore the efficacy and safety of the new approach for specific vaccines like DNA vaccines.



Greece's 'Instagram Island' Santorini nears Saturation Point

Tourists queue as they wait to take a picture from one of the balconies. Aris Oikonomou / AFP
Tourists queue as they wait to take a picture from one of the balconies. Aris Oikonomou / AFP
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Greece's 'Instagram Island' Santorini nears Saturation Point

Tourists queue as they wait to take a picture from one of the balconies. Aris Oikonomou / AFP
Tourists queue as they wait to take a picture from one of the balconies. Aris Oikonomou / AFP

One of the most enduring images of Greece's summer travel brand is the world-famous sunset on Santorini Island, framed by sea-blue church domes on a jagged cliff high above a volcanic caldera.
This scene has inspired millions of fridge magnets, posters, and souvenirs -- and now the queue to reach the viewing spot in the clifftop village of Oia can take more than 20 minutes, said AFP.
Santorini is a key stopover of the Greek cruise experience. But with parts of the island nearing saturation, officials are considering restrictions.
Of the record 32.7 million people who visited Greece last year, around 3.4 million, or one in 10, went to the island of just 15,500 residents.
"We need to set limits if we don't want to sink under overtourism," Santorini mayor Nikos Zorzos told AFP.
"There must not be a single extra bed... whether in the large hotels or Airbnb rentals."
As the sun set behind the horizon in Oia, thousands raised their phones to the sky to capture the moment, followed by scattered applause.
For canny entrepreneurs, the Cycladic island's famous sunset can be a cash cow.
One company advertised more than 50 "flying dresses", which have long flowing trains, for up to 370 euros ($401), on posters around Oia for anyone who wishes to "feel like a Greek goddess" or spruce up selfies.
'Respect Oia'
But elsewhere in Oia's narrow streets, residents have put up signs urging visitors to respect their home.
"RESPECT... It's your holiday... but it's our home," read a purple sign from the Save Oia group.
Shaped by a volcanic eruption 3,600 years ago, Santorini's landscape is "unique", the mayor said, and "should not be harmed by new infrastructure".
Around a fifth of the island is currently occupied by buildings.
At the edge of the cliff, a myriad of swimming pools and jacuzzis highlight Santorini is also a pricey destination.
In 2023, 800 cruise ships brought some 1.3 million passengers, according to the Hellenic Ports Association.
Cruise ships "do a lot of harm to the island", said Chantal Metakides, a Belgian resident of Santorini for 26 years.
"When there are eight or nine ships pumping out smoke, you can see the layer of pollution in the caldera," she said.
Cruise ship limits
In June, Prime Minister Kyriakos Mitsotakis floated the possibility of capping cruise ship arrivals to Greece's most popular islands.
"I think we'll do it next year," he told Bloomberg, noting that Santorini and tourist magnet Mykonos "are clearly suffering".
"There are people spending a lot of money to be on Santorini and they don’t want the island to be swamped," said the pro-business conservative leader, who was re-elected to a second four-year term last year.
In an AFP interview, Tourism Minister Olga Kefalogianni echoed this sentiment and said: "We must set quotas because it's impossible for an island such as Santorini... to have five cruise ships arriving at the same time."
Local officials have set a limit of 8,000 cruise boat passengers per day from next year.
But not all local operators agree.
Antonis Pagonis, head of Santorini's hoteliers association, believes better visitor flow management is part of the solution.
"It is not possible to have (on) a Monday, for example, 20 to 25,000 guests from the cruise ships, and the next day zero," he said.
Pagonis also argued that most of the congestion only affects parts of the island like the capital, Fira.
In the south of the island, the volcanic sand beaches are less crowded, even though it is high season in July.
'I'm in Türkiye
The modern tourism industry has also changed visitor behavior.
"I listened (to) people making a FaceTime call with the family, saying 'I'm in Türkiye," smiled tourist guide Kostas Sakavaras.
"They think that the church over there is a mosque because yesterday they were in Türkiye."
The veteran guide said the average tourist coming to the island has changed.
"Instagram has defined the way people choose the places to visit," he said, explaining everybody wants the perfect Instagram photo to confirm their expectations.