At some point in the year or so prior to the pandemic, I took care of a patient who had collapsed at a bus stop. There was a police officer nearby who immediately identified the patient as being in cardiac arrest, began CPR, notified EMS so the patient could be defibrillated, and they got the patient’s pulse back prior to arriving at the emergency department. My job was really pretty simple. I inserted a breathing tube, I ordered the EKG and identified that the patient was having an ST elevation MI (heart attack) and would require an emergent cardiac intervention. I activated the interventional cardiologist and cath lab team. The interventional cardiologist put 1 or more stents into the patient, and the patient survived to discharge neurologically intact. This was a huge save and also not nearly as common as TV medical shows would have you believe. By now, most have heard about the on the soccer field cardiac arrest of Danish soccer star Christian Eriksen last Saturday. He also received a fairly rapid defibrillation by an AED to regain his pulse and appears neurologically intact at this point. He underwent defibrillator placement today and I read he was discharged. Pretty amazing. These two cases are by far the exception to the rules of the outcomes when someone has a cardiac arrest. When patients are brought to me in cardiac arrest and are still getting chest compressions, the likelihood of getting a pulse back, let alone having a meaningful recovery neurologically intact, is incredibly low. By the time someone has been brought to me, they have likely been in cardiac arrest for at least 15 to 20 minutes. Chances of survival at that point are in the single digits. The best chance that someone has of surviving a cardiac arrest is getting immediate bystander CPR and rapid defibrillation (if appropriate). There have really been some great saves in this area over the last several years of young people who unfortunately had a cardiac arrest but received bystander CPR and rapid AED defibrillation to save their lives. The take-home message is that everybody should learn CPR. If you do not learn it at school or work, it probably makes sense that every religious organization, community group, or team spends a couple hours each year refreshing their training on how to properly do chest compressions. You should know where AEDs are located in your place of employment and honestly, because of my profession, I always keep an eye on them when I walk through airports or malls as well. It can be really challenging to find a pulse in an unresponsive patient in an environment that is not used to dealing with sick people. When people describe to me what happened in the moments before somebody collapses, it’s not uncommon to hear that the patient had some seizure activity and then collapsed. Those 1 to 2 seconds of seizure activity are not a seizure but rather it’s someone dying. If you witness something like this, it requires rapid action and decision making. Early administration of chest compressions can save lives, and everyone should be trained in CPR.
Back to COVID. The Delta variant continues to increase in the US. As a frontline doctor, I don’t know what variant a patient has. The state and federal labs are analyzing a small percentage of the positive covid tests and using that data to track variant progression. It’s not perfect but it’s a consistent process week over week and provides useful information to health officials. The Delta variant definitely appears more transmissible (perhaps 2x the original strain but up to 4x the risk for hospitalization in unvaccinated people) though fortunately, fully vaccinated people remain protected. Cases in the US are no longer declining. We are seeing slight upticks in the numbers of cases, particularly in areas where vaccination rates are not high. Analysis reported this week found that “states with higher vaccination rates now have markedly fewer coronavirus cases…and states with lower vaccination rates have higher rates of hospitalization.” Looking at the UK, which has a well vaccinated population like the US and has a very high percentage of Delta variants making up new cases, we see a pretty substantial rise in new cases over the last month whereas the number of deaths has remained flat. This shows the increased transmission of the Delta variant, including some vaccinated people, but that the vaccine protects you from bad outcomes. The first vaccine used in the UK was the AstraZeneca one. Since then, Pfizer is also used. That is why vaccine data on the Delta variant only includes those two. Moderna is expected to perform like Pfizer and there just isn’t enough data yet about J&J. With that said, studies show that Pfizer is about 96% effective against hospitalization from the Delta variant after two doses while AstraZeneca is about 92% effective against hospitalization. The efficacy after only 1 dose is not nearly as effective against the Delta variant compared to the efficacy of one doze with the original variant. Recall that the early vaccine studies looked at effectiveness against the disease. Now, the variant has changed the outcome measure to be preventing hospitalization.
The Centers for Disease Control and Preventions Vaccine Advisory Committee met today to discuss the possible links between the mRNA vaccines and myocarditis in young males. One of the questions is whether recommendations for vaccination should change for this age group. I have also heard through the grapevine that the FDA may require more data before they approve the vaccine for children under 12, which would delay immunizing this age group. Both Pfizer and Madura plans to enroll about 3000 pediatric patients though there is some discussion about whether their enrollment should be upwards of 10,000. However, in order to see something that is as rare as myocarditis and draw scientific inclusions, you to have to have a lot more than 10,000 patients. There are about 800 cases of reported myocarditis secondary to vaccinations. I suspect this number is actually low and that more cases exist. While I have not personally taken care of any patients who ultimately had myocarditis secondary to the vaccine, I certainly heard about a handful of patients that were admitted where vaccine related myocarditis was in the differential diagnosis. But of those 800 cases that have been reported, the overwhelming majority have done very well, typically improving with anti-inflammatory medicine like ibuprofen and sometimes infusions of antibodies. In looking at the data, a COVID infection is much more likely to cause myocarditis than the vaccine. Additionally, COVID has already led to the hospitalization of thousands of children under the age of 18. The rare cases of vaccine induced thrombocytopenia (VIT) secondary to the Johnson & Johnson vaccine (28 cases out of 8.7 million US recipients of the vaccine as of late May) led to a pause in administration of the vaccine so doctors could be educated on the diagnosis and treatment of the condition. This was important because the traditional treatment for blood clots can make those with VIT worse. VIT patients required a different kind of medication than we traditionally used to treat the blood clots. However, diagnosing and treating myocarditis secondary to the vaccine is similar to how we diagnose and treat non-vaccine related myocarditis. We use an EKG, lab tests, and anti-inflammatory medicine typically. Therefore, pausing vaccine administration to adolescent males is not necessary at this time.
The other big news this week on vaccines comes out of Maryland where Novavax announced the results of it’s clinical trial. Looking at approximately 30,000 people in the US and Mexico, in a timeframe that included variants, scientists found an efficacy rate of about 90%. That’s pretty impressive.
There was an interesting study released this week looking at the reinfection rate of patients who had severe COVID. From the University of Missouri, who followed 9100 patients, only 0.7% of them got reinfected a second time with a mean re-infection period of 116 days. However, 3.2% of them died. Risk factors included asthma and nicotine use. What’s interesting about this study is that is clearly shows that re-infection is possible, albeit uncommon, and that we don’t really know how long the duration of immunity from an initial infection lasts.
Our internal data continues to look very good. If you go back to late April/ May 2020, when ED volumes were 50% of what we’re seeing now, we were diagnosing 50-60+ cases a week of Covid among our symptomatic patient group. Our percent positive rate among that subgroup of patients was often 40-50% in any given week. For most of the time since then, our percent positive rate for patients we classified as symptomatic, and would therefore require our Covid isolation, was about 20 to 35%. Over the last 4 weeks or so, this percent positive rate has fallen to below 10%. For the first time since I started keeping track of the data, we had zero patients test among those that the providers considered symptomatic and at risk of having Covid. This is fantastic though unfortunately it does not mean we were completely Covid free this week. We did have a handful of positive tests among our asymptomatic patients representing a 1% positivity rate among all Covid test performed in the emergency department. This is the lowest rate since I started keeping track of the data in April 2020.
Over 600,000 Americans have died of COVID. We have a clear path out of this pandemic with vaccinations yet about a third of Americans remain “vaccine hesitant.”
Science matters. Get vaccinated. Wear a mask when you’re supposed to. We’re almost there.
Mike