More and more studies are coming out on COVID19 “recoveries” (i.e. not deaths) as time goes by. Studies are starting to show consistency across populations, which means the full picture is getting clearer and clearer. I posted on long-term effects among hospitalized Italians on July 11.
To compliment these findings, CDC just published symptoms among OUTPATIENT adults (i.e. not hospitalized) in the US. What did they find?
1/3 of adults did not return to normal
Even among younger adults (18-35), 1/5 did not return to normal
Among those that didn’t return to normal, the most common symptoms were shortness of breath, fatigue, and cough (same as Italy study)
Among those that claimed they returned to normal after 3 weeks, 34% still reported symptoms
“This report indicates that even among symptomatic adults tested in outpatient settings, it might take weeks for resolution of symptoms and return to usual health”. As a comparison, over 90% of outpatients with flu fully recover within 2 weeks. Once again, COVID19 is not the flu.
Never thought my physiology degree would be worth anything. But here we are!
Our immune system has special types of cells with different functions: 1) B-cells (antibodies) latch on to the virus so they can’t enter the cells; 2) T-cells find and destroy the virus (and then remember who they need to destroy). T-cells have been found effective in MERS and SARS, but their role in COVID19 has not been clear.
One study in Singapore was just published on COVID19 t-cells. Briefly, they found: • T-cell response is high among mild COVID19 cases (unlike the antibody studies we have seen) • Interestingly, healthy people have COVID19 t-cells. This be due to exposure to other related coronaviruses, such as the common cold and SARS. This MAY explain why some people control the infection (and recover much better) than others. • T-cells lasted over 17 years among SARS survivors, and the SARS t-cells WORK against COVID19
So far, all vaccines being developed target B-cells (antibodies), but scientists are starting to explore the potential of leveraging T-cells for therapeutic options. The problem is t-cells are much more complicated to analyze compared to antibodies. If fact, they require a special laboratory. So, we can’t do large population-based studies like we saw in Spain (https://yourlocalepidemiologist.com/?p=214).
To my knowledge, there are only three other published studies on this topic (regarding COVID19). I’ve included them below.
Thought I would sprinkle some of my own research in this blog because…why not?
For those of you that don’t know, I am a violence and injury epidemiologist. My research lab focuses on how violence is contagious (just like infectious diseases) and predictable. Because if it’s predictable, then it’s preventable.
As we ALL know by now, COVID19 has not only caused major medical problems in our community but has caused social problems. The strains and stresses of the COVID-19 pandemic (like job loss, financial struggles, food insecurity, mental health, and lack of social support) have exacerbated the risk of violence at home.
My colleagues and I are continually working to understand how the stay-at-home orders/school cancelled impacts child abuse.
Figure 1 shows the impact of COVID19 on child abuse hospital visits in 2020 compared to 2019. Briefly, we found less kids are going to the hospital for child abuse after stay at home orders compared to last year. Unfortunately, though, we hypothesize that this isn’t because child abuse is getting better, but rather because kids are interacting less with mandatory reporters (i.e. teachers, daycare teachers) and the public.
Among kids that ARE going to the hospital for child abuse, physicians are reporting even MORE severe injuries (traumatic brain injuries, intentional burns) than before the pandemic. Typically, a hospital system has 5-10 child abuse deaths per year. It is not uncommon for a hospital to now report 2 child abuse deaths in one week.
The realities of this crisis are immediate. Researchers and clinicians are working hard to urgently address this public health crisis in real-time.
Prevention can also start at home. The Prevent Child Abuse America posted some fantastic resources for parents, children, educators and everyone else. This includes tips for staying connected to the community, tips for staying engaged as a family, and tips to manage stress and anxiety. Check it out: https://preventchildabuse.org/coronavirus-resources/.
These efforts are especially relevant given that a lot of schools are delaying in-person school. While this delay is desperately needed medically, it will have an impact on kids’ health and safety.
Love, your local (violence) epidemiologist
Source: Data comes from my lab in which we are working directly with pediatric hospitals. Data is not published; this is only a high-level preliminary report. We are working on it!
Over the weekend, a study was released on the longevity of COVID19 antibodies in New York. This is important in regards to the effectiveness of vaccines.
This new study just focused on symptomatic and confirmed COVID19 cases. Bottom line? Antibodies were found to last at LEAST 3 months (the study was only 3 months long). More details: Scientists followed 19,763 hospital employees who tested positive for COVID19. After 52 days of symptom onset, the scientists took a blood draw to test how many antibodies people had: 7% made low levels of antibodies; 22% made medium; and 70% made high levels of antibodies. Then the scientists took a blood draw 82 days after symptom onset. Antibody counts were relatively stable. Only one person had zero antibodies.
This study both compliments and contradicts a smaller study conducted in China (Long et al., I posted earlier). Their bottom line? Antibodies lasted at least 8 weeks, but not for everyone. More details: Among symptomatic patients, 84% had antibodies during the first follow-up and, of those, 87% had stable antibodies at the second follow-up.
So which study is “correct”? The NY authors state that the discrepancy between studies is likely due to evaluating different types of antibodies. ALSO it typically takes hundreds (if not thousands) of studies to clearly see the full story. Replication among different populations is key to make generalizations. However, the first few studies gives us an initial peak into biological mechanisms.
So we know that the antibodies fights off re-infection among primates and we know that transferring plasma among humans also reduces virus replication. We also know that antibodies from other coronaviruses (like MERS and SERS) last 2-3 years. This NY study will continue to collect information on the employees to continue to track antibody responses over time. I look forward to seeing their follow-up results.
Love, your local epidemiologist
Data sources: Figures by me using data from the following two studies: Wajnberg et al., SARS-CoV-2 infection induces robust, neutralizing antibody responses that are 2 stable for at least three month. 2020; Q. X. Long et al., Clinical and immunological assessment of asymptomatic SARS-CoV-2 infections. Nat Med, (2020).
Many dashboards are reporting the number of people that have “recovered” from COVID19. “Recovered” means “not dead” in the majority of reporting systems. This does NOT necessarily mean “back to normal”.
We are starting to see the long-term effects of COVID19 on survivors. We (certainly I) have been anxiously waiting for peer-reviewed data to be published. We are in luck, because one was published yesterday in JAMA. This was a small sample of hospitalizations in Italy, but still has very important implications (and is a fantastic first step).
The figure I created describes the study using data from the manuscript. Important take-aways: -After 60 days, ONLY 13% of hospitalized patients fully recovered (meaning not having one symptom) -The majority of patients had 3+ more symptoms 60 days after their COVID19 infection and after 47 days of being in the hospital -Almost half of the hospitalized patients reported a WORSE quality of life -Almost half of the hospitalized patients were still having a hard time breathing
While CFR is holding steady (actually we are starting to see an uptick- that’s for another post), cases are increasing. Decreased deaths is fantastic. However, this isn’t the whole story.
Tracking the way in which humans moved before and during the pandemic has been a very innovative way in which epidemiologists have been able to describe (and predict) COVID19 spread. Specifically, many scientists are using cell phone data to track movement.
Yesterday, the Lancet (a highly reputable scientific journal) published a study in which they wanted to answer… HOW strong IS the relationship (i.e. correlation) between movement and COVID19 spread. Spoiler: VERY strong.
We can see this visually too. For example, as of today, there are 14 hot spot states. These states have very similar patterns in movement to non-essential businesses (Figures). The blue line indicates change in movement to non-essential buisnesses. For example…
In Texas, at the peak of the stay-at-home orders (April 8), there was a 70% reduction in movement to non-essential places. In other words, people moved 70% less to non-essential buissness than before the pandemic. Which was great; it worked to curve spread. However, since then, people have been moving more and more to non-essential businesses. In mid-June, Texans only moved 15% less than before the pandemic. This means they were almost back to “normal”. This was followed by exponential increase in COVID19 cases.
We see the same with AZ, FL, and CA (although CA is not as dramatic).
As a comparison, I also included NY. Movement to non-essential businesses stayed constant for almost 2 months, then once cases were down, SLOWLY started to increase. The highest NY has gone is 55% reduction in movement. They haven’t even gotten close to the 15% reduction like we see in Texas.
Translation: Your movement to non-essential places MATTERS! We can all reduce our movement to keep this pandemic under control.