A mum says she's shocked after learning she tested positive for Covid-19, despite receiving the second dose of the vaccine a month earlier.
Gillian Plummer, 34, from the US state of Connecticut, was diagnosed with coronavirus last week.
She said her husband and two daughters all tested positive after feeling "pretty ill" and suffering from with fevers, headaches, aches and pains.
However, Ms Plummer told WTNH the day before she returned a positive test, she went for a run.
She said she didn't feel overly tired, but likened it to a sinus infection, with no sense of taste and smell.
"I definitely felt off and I was sick,” Ms Plummer said.
“My body was fighting an infection but if it weren’t for the vaccine then I’m sure I would have been way sicker.”
Ms Plummer said her senses are slowly coming back.
There have been instances of people testing positive for the virus after being fully-vaccinated.
The Center for Disease Control and Prevention (CDC) says all coronavirus vaccines available in the US have shown they efficiently prevent people from getting the virus.
"Studies show that COVID-19 vaccines are effective at keeping you from getting COVID-19," the CDC says.
"Getting a COVID-19 vaccine will also help keep you from getting seriously ill even if you do get COVID-19."
Though the CDC warns it is not yet known how effective the vaccines are against Covid-19 variants, stating early data suggests they may be less effective against some, while more effective against others.
Covid risk in Australia still 'high'
Australia remains at as high risk of coronavirus as it was at the start of the pandemic, the nation's chief medical officer has warned.
Professor Paul Kelly's comment comes as Queensland battles two clusters of Covid-19 that link back to health workers.
NSW is also on alert as the latest outbreak outpaces Australia's vaccination rollout.
Queensland has recorded 10 new Covid-19 cases, including eight in the community, while NSW remains at zero new cases despite local exposure to the coronavirus at a party in Byron Bay.
Prof Kelly said it was important to understand the virus was circulating in the Greater Brisbane area "at least".
While 597,523 vaccinations had now been delivered, including almost 56,000 on Monday, there was still a high risk of outbreaks and serious illness.
"At the moment we are at as high a risk as we've been since the beginning of the pandemic," Prof Kelly told reporters in Canberra.
"We know as we mostly open and there are very few restrictions on our movement ... outbreaks can spread quickly, and so that's why that very strong public health response is absolutely crucial at the moment.
"The more vaccine that gets out there, the more people that are protected, that will decrease the outbreaks in the spread over the coming months."
Prof Kelly said all efforts were being made to get vaccines out the door "as quickly as we can", as he urged states not to stockpile Pfizer because the Commonwealth had enough to cover the required second doses.
He said wastage of doses was being monitored but remained small.
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