(CNN) The White House is expected to advise most Americans to get a third Covid-19 dose, a move that will align the US with a growing number of rich countries that have turned to booster shots in the face of the highly transmissible Delta variant and waning immunity.
Q: Are boosters unusual when it comes vaccines?
A: No, needing additional shots of a vaccine is not at all unusual, CNN Medical Analyst Dr. Leana Wen says. Many vaccines require multiple doses to achieve full immune protection, like the polio vaccine, for example, which requires four doses, or the hepatitis vaccine, which needs three. There are other vaccines that require occasional "boosts" because immunity may wane over time, such as the tetanus-diphtheria vaccine.
Other vaccines need to be administered more often, like the flu vaccine, which requires an annual shot. This is not so much to boost our immunity, but because each season there are new strains targeted by the vaccine, Wen explains.
As Covid-19 is a relatively new disease, we don't yet know if one more dose will be required to complete a course, as in the case of the three-dose hepatitis vaccine; if occasional "boosts" for immunity may be needed, like with the tetanus shot; or if new strains may emerge, which require updated shots to target them.
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New Zealand reports its first case of Delta, goes into national lockdown
New Zealand went into a nationwide lockdown late Tuesday night, hours after confirming one Covid-19 case -- the first locally transmitted infection since February. On Wednesday, New Zealand authorities announced they had confirmed another six cases, all linked to the original.
The outbreak marks the first time New Zealand has confirmed the presence of the Delta variant in the community and authorities are still determining how it got there. The country shut borders to almost all foreigners last year and required most incoming travelers to go through state-run quarantine -- an approach that has allowed New Zealand to avoid the devastating waves seen in other countries, and bring life largely back to normal.
Now the country joins at least 142 others that have reported cases of the Delta variant. New Zealand's director-general of health, Ashley Bloomfield, warned Wednesday that it could see between 50 and 120 more cases based on modeling that took Delta into account. "Our job now is to find any and every case," he said.
Some politicians are using Covid-era misinformation to side with lies
The Covid-19 pandemic has presented a golden window to undermine confidence in the media and, in some cases, for world leaders to launch outright assaults on some of the most respected and important journalistic institutions in their countries, Luke McGee writes.
This month, the Polish parliament passed a bill that could shutter the country's largest independent news channel, TVN24, a broadcaster that frequently criticizes the Polish governing party. Also this month, Austrian Chancellor Sebastian Kurz put forward a plan that would effectively pull funding from the nation's oldest newspaper.
All of this could be tied to the timing around the Covid-19 pandemic, media experts say. "In times of crisis trust in government goes up because people just want somebody to fix things, so you see people rally around the flag," Ben Page, chief executive of polling firm Ipsos MORI said, adding that these spikes in support provide a window of opportunity that "distracts from what you are doing elsewhere." And if you are a politician seeking to capitalize on this, whacking and weakening the press is a relatively easy proposition.
Child Covid cases are increasing, and this could be just the beginning
Cases of Covid-19 among children have steadily increased since the beginning of July, according to a report from the American Academy of Pediatrics (AAP). More than 121,000 child Covid-19 cases were reported in the US last week, which the AAP called "a continuing substantial increase."
Public health experts continue to advocate for children to wear masks in school, especially as children under 12 are currently ineligible for the vaccine. But to their frustration, some state governors have attempted to ban such requirements. "Why tie the hands of the public health officials behind their backs? You have two weapons here, one is vaccines the other is masking, and for children less than 12 that's the only weapon they have," Dr. Paul Offit, a member of the US Food and Drug Administration's vaccine advisory committee, told CNN. A study published in the Proceedings of the National Academy of Sciences further supports the case for masking. It found that other mitigation measures -- such as physical distancing and handwashing -- are "insufficient by themselves" in curbing the pandemic without mask use, too.
Meanwhile, the majority of American parents plan to send children into school this year, but want more information about Covid safety measures that are in place, according to a survey published Wednesday by the State and Territory Alliance for Testing, Rockefeller Foundation, and RAND Corporation. Just 27% of parents said they knew in detail which Covid-19 prevention measures had been implemented by their child's school, according to the survey, with 60% saying they would like more information about safety precautions.
Pregnant? Get vaccinated.
The CDC has strengthened its recommendation for pregnant people to get inoculated. "Evidence about the safety and effectiveness of COVID-19 vaccination during pregnancy has been growing. These data suggest that the benefits of receiving a COVID-19 vaccine outweigh any known or potential risks of vaccination during pregnancy," the CDC said in its updated guidance on its website.
Pregnant women are at an increased risk of getting severely ill from Covid-19 and "adverse pregnancy outcomes, such as preterm birth," according to Sascha Ellington, team lead for emergency preparedness and response in the CDC's Division of Reproductive Health. "This vaccine can prevent Covid-19, and so that's the primary benefit," she added.