Vaccine

No Vaccination? No Daycare, Say Australian Legislators

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A children’s doctor injects a vaccine against measles, rubella, mumps and chicken pox to an infant on February 26, 2015 in Berlin, Germany. (Sean Gallup/Getty Images)

Australia might soon ban unvaccinated children from attending preschools and daycare. Australian Prime Minister Malcolm Turnbull didn’t mince words on the proposed law, dubbed “No Jab, No Play.”

“This is not a theoretical exercise – this is life and death,” he said. “If a parent says ‘I’m not going to vaccinate my child’, they’re not simply putting their child at risk, they’re putting everybody else’s children at risk too.”

Australia has been moving toward stricter vaccination laws for years. In 2015, the federal government stripped welfare and tax benefits from parents of unvaccinated children, a move that led to an increase of about 200,000 child vaccinations.

Vaccination laws that restrict unvaccinated children from attending schools already exist in New South Wales, Queensland and Victoria. But Turnbull and the Australian Medical Association want to enforce them nationwide.

“If you, as a parent, expect the community to support you by either welfare payments or access to care, then you need to do your bit to contribute to that community by protecting other children,” Michael Gannon, president of the Australian Medical Association, told Fairfax Media.

Still, some think Australia’s this strong-arm legislation could empower the anti-vaccination movement.

“People without any previous interest in vaccination may defend anti-vaccination activists and join their cause because they are concerned about the threat to civil liberties,” said Julie Leask, a professor and researcher at the University of Sydney.

Like in the U.S., there’s a small but loud movement of anti-vaccination Australians (or “vaccination skeptics“) who believe vaccines cause autism and other medical problems – despite the overwhelming evidence that vaccines are safe. These beliefs can permeate entire communities and facilitate outbreaks of Victorian-era diseases.

Anti-vaxxer protest

(Photo: NICHOLAS KAMM)

One anti-vaccination mother living in a suburb outside of Sydney recently proposed starting a daycare center for unvaccinated children.

“Many families are concerned about vaccinating. Yes it’s in response to No Jab No Play,” the post read. Alarmingly, some were supportive of the idea, suggesting they open similar daycares in nearby cities.

Such a move could put whole communities at risk by weakening herd immunity.

Herd immunity is all about strength in numbers. Society becomes protected from outbreaks when enough people are…

DNA may offer rapid road to Zika vaccine

Zika DNA vaccine
A Zika vaccine that’s made of DNA could be a safe and fast way to protect people from the virus, which can cause birth defects.

GIVE IT A SHOT

Last August, scientists injected a potential vaccine for Zika virus into a human being — just 3½ months after they had decided exactly what molecular recipe to use.

In the world of vaccine development, 3½ months from design to injection is “warp speed,” says vaccine researcher Nelson Michael of the Walter Reed Army Institute of Research in Silver Spring, Md. Clinical trials can take years and epidemics can burn out before vaccines make it to doctors’ shelves. Even vaccine creation is typically sluggish.

But in this case, the vaccine is a bit of DNA, which means scientists can get moving fast. Unlike some traditional methods, DNA vaccines don’t use dead or weakened viruses. Instead, they rely on a snippet of genetic material. This “naked” DNA carries, for example, the blueprints for Zika proteins. It’s just a long sequence of DNA blocks.

With DNA vaccines, “it’s easy to move very quickly,” says Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in Bethesda, Md. “All you need to do is get the right sequence, and Bingo! — you’re there.”

Historically, though, DNA vaccines have been deviled with drawbacks. “They work absolutely fantastically in mice,” says infectious diseases physician Anna Durbin of Johns Hopkins Bloomberg School of Public Health. But “they fail miserably when we use them in humans.”

Researchers at the infectious diseases institute will soon begin the second phase of human clinical trials for a DNA vaccine candidate for Zika, vaccine clinical researcher Julie Ledgerwood said February 6 in Washington, D.C., at an American Society for Microbiology meeting on biothreats. The virus made headlines last year as it continued its tear through the Americas, and scientists confirmed its link to birth defects, including microcephaly (SN: 12/24/16, p. 19). Ledgerwood hopes to see efficacy data on the vaccine by the end of 2018.

“Ultimately, we want a vaccine that can prevent congenital Zika infection,” she said. “We think the DNA vaccine platform is an opportunity to do things safely and very quickly.”

Government researchers aren’t betting everything on DNA, though, Fauci points out. “We’ve got multiple shots on goal here,” he says. A slew of other vaccine candidates, based on both traditional and new techniques, are also in the works. But the DNA vaccine has stepped up to the plate first, and the world will soon see if it can deliver.

“If it works,” Durbin says, “we’ve hit a home run.”

Making a DNA vaccine is simple, in principle. Scientists synthesize genes from a pathogen, insert them into a circular strand of DNA called a plasmid, make lots of copies and then inject the purified plasmid into a person. “You can literally build a DNA vaccine in weeks,” says Dan Barouch, an immunologist at Beth Israel Deaconess Medical Center and Harvard Medical School. The approach is flexible, too, he adds. Researchers can tinker with the DNA building blocks in the plasmid, adding bits from other viruses that might ultimately enhance the immune response.

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Immune trigger

For a DNA vaccine against Zika, scientists insert genes for Zika proteins into a circular piece of DNA called a plasmid. Many copies of the plasmid are injected into muscle. Some of the DNA travels into cells’ nuclei, where it is used to make messenger RNA. After exiting the nucleus, mRNA helps build Zika proteins, which can form viruslike particles that trigger the immune system to make antibodies.

Zika DNA vaccine process

Barouch’s team was the first to report a Zika DNA vaccine that offered protection in mice — in a study published last June in Nature. Five weeks later, he and colleagues reported in Science that the vaccine, and two others created via different strategies, worked well in monkeys, too. And in September, a team led by government scientists, and including Barouch as a coauthor, came out with two additional DNA vaccine candidates, described in Science.

It’s one of those additional candidates, called VRC 5283, that the infectious diseases institute plans to test in…