Why did millions of Americans skip the second dose of the Covid-19 vaccine?
In the United States, approximately 8% of people who took the first dose of the Pfizer-Biontech vaccine or Moderna covid-19 did not return to receive the second dose, according to a recent report in the US newspaper. New York times. Experts believe there are several reasons for this number.
Some people may have read speculation that a single dose will be sufficient [para proteger contra o coronavírus]Angela Rasmussen, a virologist, of the Organization for Vaccines and Infectious Diseases (VIDO), told DW. According to her, this idea will instil in people a false sense of security.
Another reason that may discourage some vaccines from taking the second dose is fear of possible adverse reactions from the immunization. “Some people may have side effects associated with the first dose and decide for themselves that they do not want to try it again with the second dose,” says the virologist.
“I think the health insurance has advised other people not to receive the second injection, and that if they actually had an allergic reaction or had a bad history of receiving second doses – it would probably be a minority of cases, but I think some people for medical reasons they were advised not to take The second dose, “Rasmussen adds.
The specialist also cites other possible causes, such as logistical obstacles beyond the control of vaccines, as well as canceled vaccination schedules or pharmacies that have not stocked doses of the correct type of vaccine. Perhaps a few people still have simply forgotten that they need a second injection.
Social factors can play a role as well. According to Dr. Lisa Cooper, chair of the Johns Hopkins Center for Equality in Health, lower classes and African Americans face specific structural barriers to getting to even the first dose of a vaccine.
“ If you don’t have a cell phone or fancy computer, you might be more comfortable using the regular phone – but some vaccination centers don’t have a number to call, and the only way to register is [para se vacinar] Cooper said in an interview with DW.
“Even if you can [se registrar]You will find that the vaccination site is on the other side of town, and you do not have a car – do you want to use public transportation during COVID-19? It will cost you extra money to do all these things. “
Economic concerns also contribute to hesitation about a vaccine. Many American workers say they would like to be vaccinated, but they don’t always get support from their employers. To avoid this, US President Joe Biden has asked employers to grant paid leave to allow their employees to get vaccinated, and offered tax breaks to small and medium-sized businesses to cover costs.
Is the vaccine dose sufficient?
Experts have repeatedly explained that in order to obtain greater and long-term protection against the Corona virus, it is necessary to take two doses of the vaccine – in the case of vaccinations that require two doses, of course. There are studies that indicate that the first dose, at least in the short term, does indeed provide some protection, but it is not clear how long this protection will last.
Two recent studies conducted by the UK’s National Institute of Statistics and the University of Oxford showed that people who were vaccinated had a strong immune response after receiving either dose.
One study reported a 72% reduction in symptomatic infections among people who received the first dose of the Pfizer-Biontech and AstraZeneca-Oxford vaccines. After two doses of Pfizer-Biontech, there was a 90% reduction in symptomatic inflammation. Protection data after the second dose of AstraZeneca was still available.
Queen Boyles, the study author and researcher at the University of Oxford, points out that taking a second dose of your immune system leads to more effective and longer-lasting protection against Covid-19. “It is very important that you receive the second dose.”
“As with any infectious disease, to begin with [após a primeira dose] “You’re going to have high protection and then that efficacy will decrease,” Boyles told DW. When looking at antibody responses, the decline is relatively rapid. The second dose is very preventive and increases antibody levels even more, especially in the elderly. “
According to virologist Angela Rasmussen, the problem is not that the second dose will not work if the patient waits longer to receive it, but rather that he may not have the protection he thinks they have during that time in between doses.
“What people might be ignoring is that this second dose is really necessary to have these long-term immune responses,” she says.
Whoever gets sick with Covid-19 can only take one dose?
An American study by Cedars-Sinai Medical Center of more than 260 people showed that “a single dose of the Pfizer-Biontech vaccine in individuals who have already been infected with covid-19 generates an immune response similar to that of individuals who received the two recommended doses.”
This means, according to the researchers, that the data indicates that a second dose may not be necessary for those who have recovered from the Coronavirus infection. The question is how effective a single dose is.
“Many individuals have been infected with covid-19, and availability of the vaccine remains limited in most regions. Therefore, the only dose in affected individuals is [histórico] Covid-19 can greatly speed up the number of immunized people and aid in reaching community levels [de vacinação] Study co-author Jonathan Brown, professor of medicine at Cedars-Sinai Medical Center, told DW.
Another survey by the Penn Institute for Immunology at the University of Pennsylvania found that people who have recovered from the infection had a strong antibody response after the first dose of vaccines using mRNA technology, such as the Pfizer-Biontech immune system.
In a press release, the immunologist and co-author of the study E. John Were said, “These results are encouraging for both the vaccine effectiveness in the short and long term.”
In Germany, the Standing Committee on Vaccination (Stiko, abbreviated in German) recently updated its reports to include new data recommending that, for people who have developed the Covid-19 virus, “one vaccine should be considered, but not earlier than six months after recovery. […]Because of the immunity present after the infection. “