CNN: Who is now eligible to receive an extra booster dose? Dr. Leana Wen: Prior to announcements this week by the FDA and the CDC, people with moderate to severe immunosuppression were already eligible for an extra booster dose. Now, a much larger group is eligible. This includes two subsets of people. First, individuals 50 years of age or older who have received three previous doses of either Pfizer or Moderna, and who are at least four months away from their last vaccine dose, are eligible for another mRNA booster – either Pfizer or Moderna. Second, all adults – regardless of age – who received an initial Johnson & Johnson vaccine and then a booster at least four months ago can now receive a second booster dose with an mRNA vaccine, again either Pfizer or Moderna. CNN: Now that many more people can get a second boost, should they? Wen: First of all, I want to emphasize the importance of taking the first booster dose. According to the CDC, about half of all eligible Americans have not yet received this first aid. This includes an astonishing 1 in 3 people aged 65 and over. There is ample evidence to suggest that the original amplifier is significant, especially against Omicron variants, including the dominant BA.2 strain. During a time when BA.1 was the major variant, the effectiveness of two doses of the serious disease vaccine dropped to 79%, according to a CDC study. The effectiveness of three doses remained high, at 94%. The data around the second souvenir are less clear. Much of the research comes from Israel, where the fourth installments have been widely available since late January. A study there in adults over the age of 60 found that those who received the fourth Covid-19 vaccine had a 78% lower risk of dying during the increase in Omicron compared with those who had a third vaccine at least four months earlier. However, the death toll was low in both groups. Another Israeli study, published in the New England Journal of Medicine, found that while a fourth dose increased antibodies, it did not boost protection much and those who were infected were slightly symptomatic, regardless of whether they fired three or four shots. Complicating matters is that it is not clear how long the enhanced protection against the fourth dose will last. All of this tells me that the question of whether people should take a fourth dose is not easy to answer. This may not be a general recommendation to everyone, but a detailed guide that is tailored to each individual’s medical condition. CNN: What are the factors that people need to consider when deciding whether to take a second dose? Wen: First, consider your medical risk factors. If you are elderly and have multiple medical conditions, you are more likely to become seriously ill with Covid-19. Certainly, if you are moderately or severely immunosuppressed, this should tilt the scales in favor of taking the extra booster dose now. On the other hand, if you are generally healthy, you are still very well protected from serious illness due to protection from the vaccine and the initial booster dose. It is not so urgent to get the amplifier and there may also be an advantage in waiting. CNN: Why would anyone decide to wait for the amplifier? Wen: At the moment, the level of Covid-19 in the US is quite low. Experts are closely monitoring BA.2 in case it causes a new increase, but the current transmission rate in most parts of the country is the lowest it has been for months. Because the enhanced protective effect of the second amplifier may not last long, it may be best to wait until there is clear evidence of an increase before taking it. In addition, there are ongoing studies to develop an Omicron-specific amplifier. If you have not received an amplifier at all, I would not recommend waiting for this variant, but if you have already received one and especially if you are not particularly vulnerable, it may make sense to stop for now. Another group of people who are probably better off waiting are those who have recently become infected with Omicron. It is unlikely that people who have been vaccinated and become infected will be re-infected so soon. Especially if they are generally healthy people, I would also advise them to wait a little longer before receiving the extra souvenir. CNN: Is there a known disadvantage to taking the fourth dose? Wen: Extensive Israeli data analyzes have not identified any new safety concerns from the fourth dose. Hypothetically, there is concern that if one is constantly taking supplements, one’s immune system may also not be triggered if exposed to Covid-19, but this is not proven. The main disadvantage would be the issue of timing – is now the best time to take the fourth dose or is it better to stop? This will depend on each individual’s medical risk factors, as well as their risk tolerance, and in particular on how important it is for them to continue to avoid coronavirus. CNN: Some people may want to wait until a big event like international travel or a big wedding to get this extra photo. Is it a good plan? Wen: Not really. If you have not yet received your original souvenir, get it now, because this first souvenir is important for maintaining strong protection against a serious illness. Do not wait for the first amplifier. I think it is difficult to time a second amplifier around an event and it would make more sense to time it around an expected wave. That said, I can understand why people would want to be better protected for big events. Remember that there are other tools at our disposal to do this. If you want to be very careful, requiring vaccinations and then testing all visitors before meeting indoors will significantly reduce the risk. Find out where you can get treatment if you become infected. And let’s not forget the masks – a high quality mask (N95 or equivalent) protects you even if others around you do not cover. Boosters are a very important tool that can complement these other tools to help us reduce our individual risk.
