Children Vaccine

Mom to baby transmission of antibodies

We are seeing more and more evidence that moms pass COVID19 antibodies to their babies…

There have been 3 important studies that have recently come out telling the same story…

  1. Between April and August 2020, scientists tested 1,500 women who gave birth in Philadelphia. They found…
    -83 had COVID antibodies
    -Among the 83, 87% of their babies tested positive for IgG antibodies (the long lasting antibodies) after they were born
    -Transferring antibodies was not different among infants born to mothers with asymptomatic or symptomatic illness
    -In 25% of the babies, their antibody levels were 1.5 to 2 times higher than the mother’s concentration
    -The longer the time period between the start of a pregnant woman’s COVID infection and her delivery, the more antibodies were transferred to the baby
  2. From April 4 to July 3, 2020, in a single university hospital in Denmark, 1,313 women took part in a study.
    -28 women (2.1%) had antibodies against COVID
    -67% of newborns delivered by mothers with antibodies had COVID IgG antibodies.
    -Neonatal outcomes (like birth weight, APGAR value, amniotic fluid, CPAP, and blood pH) were not affected by the antibody status of the mother
  3. Another study enrolled 22 COVID+ moms and 34 COVID- negative moms and tested their cord blood after birth.
    -Antibody transfer was efficient after second-trimester infection
    -While antibodies do pass, they do less efficiently than the antibodies produced after vaccination for flu and whooping cough. But this effect was only observed in third-trimester infection.

Like always, we still have a lot of unanswered questions. We need more research to better understand two things:

  1. Do vaccine-generated antibodies behave comparably to antibodies from COVID infection?
  2. Are antibodies protective against newborn infection? If so, at what concentration?

Bottom line: We already know there are benefits to pregnant women getting vaccinated. These studies suggest that there also may be benefits to the baby. Interestingly, timing of infection (or possibly timing of vaccination) may be important to ensure baby getting antibodies.

Unfortunately, pregnant women were excluded from clinical trials (which has stirred quite the debate among scientists), so these questions will take quite a bit of time to answer.

Love, YLE

Data Sources:

Children Vaccine

Kids and COVID-19 vaccination…

We have begun age de-escalation trials. Age de-escalation means that phase I and II trials are conducted first in adults, then in older children, and finally, if relevant, in small children. Vaccines need to show safety in each stage in order to move down in age.

Vaccine sponsors have already started trials for 12+ and are drafting trial plans for younger kids. Given that kids are usually asymptomatic, the trials will probably involve regular, frequent testing. First and foremost, scientists will be looking at safety. And, unlike adult studies, the plan is for the trial endpoint to be immunity (instead of disease).

Here is the status for the age groups:

12+ years: Pfizer started in October and has now finished enrollment. 2000 kids (aged 12-15) are enrolled. Moderna started in December and are still enrolling. They are aiming for 3000 kids (aged 12-17) to enroll. Moderna is starting to open more sites (see link below to find the cities). AstraZeneca is starting next month (but not in the US). Kids in all three of these trials will receive the same dose as adults. Many are hopeful that, with a bit of luck, we can have vaccines for this group by Fall 2021.

5/6-11 years: Starting late Spring. Pfizer starting Phase I in April.

<5 years: Don’t expect data until 2022

Kids have fared much better than adults during this pandemic, mostly comprising of asymptomatic infection. So, why do kids need vaccines?

1. Herd immunity. Children are part of the transmission chain, so eventually, if we want to get to the stage of herd immunity, they have to be included. Especially, if this virus is mutating to be more transmissible. The more transmissible, the higher herd immunity we need. We are hopeful that the vaccines reduces asymptomatic spread, we just don’t know by how much. We are still waiting on studies.

2. Disease. There are kids that get very serious disease, like MIS-C, from this virus. The vaccine will provide protection among the few that will get the disease.

3. Morbidity. Long term morbidity is something we still know very little about. Especially among kids.

CDC’s Advisory Committee on Immunization Practices (ACIP) is meeting on January 27 (10a-5p EST) to discuss this very topic.

Here is the meeting agenda:…/agen…/Agenda-2021-01-27-508.pdf…

Here is the webcast link:

It is open to the public. Should be a very interesting discussion. Like always, I’ll be happy to provide you with cliff notes. Stay tuned.

Love, YLE

Data Sources:

Ethics on child vaccine trials:

Moderna Trial Info:

Pfizer Trial Info:

Kids and Herd Immunity:…/should-kids-get…/617762/

TeenCove study (if you want to enroll):…/a6dd51e8-c0a0-4ad5…/

Children Variant

Update on UK strain (and kids)…

We now know that the new variant was first found on Sept 20, 2020 in Kent and another on Sept 21, 2020 in Greater London. The new variant spread undetected until early December 2020. It’s now been identified in several countries, including several states, however spread is likely all over. The US (and rest of the world) doesn’t have nearly the variant surveillance that the UK does. (This is likely why the variant was first detected in the UK).

In the UK, the body that considers new evidence about the virus is called the New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG). They virtually met on Dec 18 and Dec 22. During these meetings, there were 3 independent analyses presented regarding transmissibility (one done by University of Edinburgh; one by Imperial College London; one by London School of Hygiene and Tropical Medicine). In short, all three analyses agreed that the new variant is somewhere between 56%-71% more transmissible compared to other variants. The R(t) is estimated to be 1.2 (which is 0.38 higher than other variants). “The committee therefore has high confidence that the new variant can spread faster than other variants currently circulating in the UK”.

In one of these preliminary analyses (by Imperial College), data suggested that there may be an increase in transmission in children aged <15 years. In the meeting minutes, this is followed in bold type by: “However, these data are preliminary, and more work is required before any firm conclusions can be reached”. The primary author of this analysis, Prof Neil Ferguson, followed up this statement saying, “We haven’t established any sort of causality on that, but we can see it in the data. We will need to gather more data to see how it behaves going forward.”

This preliminary analysis was followed by a London hospital worker (Ms Laura Duffel) stated “having a ward full of children with coronavirus”. The combination of these two events have sparked quite the concern. Ms Duffel’s claim was quickly denied by clinicians. The Royal College of Paediatrics and Child Health (RCPCH) said children’s wards are not seeing any “significant pressure” from Covid-19.

In addition, members of COVID-19 Genomics UK (COG-UK) said they are not familiar with any data to suggest kids have more transmissibility than adults. COG-UK has examined the genetics of more than 160,000 cases of coronavirus in the UK and is constantly watching how the virus evolves to see whether any of the mutations are important. They said there is more data is needed to make any comments on how it affects specific groups. 

So, in short, we need more data (story of our life). Making sweeping policy changes, like closing schools, is still unfounded in the US (in my humble opinion). We will see what the UK (and other countries) decide regarding schools soon. 

Love, YLE 

Variant info:

Nervtag meeting minutes:

More meeting minutes on the three analyses:

SAGE meeting minutes dec 22

Behaviors Children Daycare Social Distancing

COVID19 infections among kids…

Kids (<18 years) make up of 10% of COVID19 infections in the United States. Because of that, it’s taken a bit more time to have enough infected kids for meaningful analyses (compared to adults). The CDC published an important study Tuesday assessing school, community, and close contact exposures associated with child and adolescent COVID-19 infection.

The study took place from Sept to Nov 2020 in Mississippi. 397 parents of children who recently had a COVID19 test completed a phone survey. They answered questions about symptoms, close contact with a person with known COVID-19, school or child care attendance, and family or community exposures ≤14 days before the COVID test. Then, scientists compared the answers across kids with a COVID19- test to kids with a COVID19+ test. There were a couple things they found…

COVID+ kids were MORE likely to have…

  • Had close contact with a person with known COVID-19. And, this close contact was more likely to be a family member than someone at school
  • Attended gatherings with people outside their home, including social gatherings (weddings, parties, funerals, birthday parties), playdates, or to have had visitors at home

COVID+ kids were LESS likely to have…

  • Consistent mask use by students and staff members inside school or child care facilities

Interestingly, there were essentially no difference between COVID+ and kids going to…

  • Sports events or concerts (18% COVID+ vs. 20% COVID- kids)
  • In-person school or child care (62% COVID+ vs. 68% COVID-)
  • Religious services (13% COVID+ vs. 18% COVID-)
  • Restaurants (20% COVID+ vs. 16% COVID-)
  • Travel with others (5% COVID+ vs. 3% COVID-)
  • Household member working in health care (24% COVID+ vs. 21% COVID-)

Before I get the comments, here are a few important notes…

1. This doesn’t mean, for example, you have carte blanche to go to indoor restaurants. This is a study of kids. This does not mean you, as a parent, won’t get it or spread it

2. No, there is no data on teachers or staff. Yes, that would be a needed analysis. I’m sure it’s coming.

3. Yes, masks work. This study showed that adults wearing masks helps kids, especially within schools and child care center. If you need more evidence, check out my previous post (

4. Opening schools is a bit more complex than kids getting infected. Kids are less likely to get sick (and not go get a test), but they harbor the disease and have the potential to spread it to others. Unfortunately, we still don’t know the rate of transmission from kids to adults.

Finally, I would like to take a moment to recognize how quickly and hard these scientists had to have worked to get this information out to the public. Data collection ended November 5, 2020. That means, within a MONTH, they cleaned the data, analyzed the data, came to meaningful conclusions, wrote up the science, sent it up the CDC ranks for approval, responded to feedback, and submitted for publishing. For the record, this typically takes 1-2 YEARS. Absolutely incredible.

Love, YLE

Data Source: Hobbs CV, Martin LM, Kim SS, et al. Factors Associated with Positive SARS-CoV-2 Test Results in Outpatient Health Facilities and Emergency Departments Among Children and Adolescents Aged <18 Years — Mississippi, September–November 2020. MMWR Morb Mortal Wkly Rep 2020;69:1925-1929. DOI:

Children Long-term effects

COVID19 and Child Abuse (an update)

There are, no doubt, pros and cons to opening schools. On one hand, if we open schools quickly, we have the potential to introduce new hotspots and increase community spread.

On the other hand, schools are fundamental to childhood development. Kids also rely on schools for reliable meals, mental health services, social support, physical activity, and safety. In my line of research, kids rely on teachers to detect and report alleged abuse. Of those that “catch” child abuse, the majority are teachers (21% are teachers, 19% are law enforcement, 11% are social services, and 11% are medical personnel).

My colleagues and I are continually working to understand how the COVID19 pandemic (and specifically stay-at-home orders/school closure) impact child abuse. On July 22, I provided preliminary data. Here is an update…

Figure 1 shows doctor visits in which physicians diagnosed child abuse in 2020 compared to 2019. In March/April, there was an alarming drop in the number of kids going to the hospital for child abuse. Unfortunately, though, we hypothesize that this isn’t because child abuse was getting better, but rather because kids were interacting less with mandatory reporters (i.e. teachers). Among kids that WERE going to the hospital for child abuse, physicians reported 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 report 2 child abuse deaths/week in 2020.

Recently, though, we have seen child abuse hospital visits start to increase. In Aug 2020, there were 309 visits (compared to 359 visits in Aug 2019). Our next step is to analyze what is causing this increase. My hypothesis is that it’s because schools are opening.

This pandemic is stressful. Period. And the strains and stresses (like job loss, financial struggles, food insecurity, mental health, and lack of social support) are penetrating homes. Child abuse prevention can 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:

Love, your local (violence) epidemiologist

Data 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 for my community. We are working on it!


COVID19 cases and schools opening

This fall approximately 56 million school aged children started school in the US. Are kid COVID19 cases increasing compared to before school?

A study was published this morning by the CDC looking at kid cases over time. There’s a lot to unpack, but here is a high-level report of results.

Since March 1…

277,285 confirmed kid cases of COVID19-37% of cases were children (5-11 years); 63% were adolescents (12-17 years)

5% of confirmed cases reported no symptoms

3% of cases had an underlying condition

Asthma was most commonly reported underlying condition among kids (55%)

1.2% of kids were hospitalized (of those hospitalized, 16% had underlying condition)

<0.01% (51) kids died

From March 1- September 19…

Kid cases peaked in July (just like adults)

We are seeing a small uptick in kid cases in September (just like adults)

Test positive rate (TPR) among kids has been decreasing since June

On Sept 19, TPR among children= 5%; TPR among adolescents=7.8%. These numbers are beyond fantastic.

Translation: As long as we have COVID in the community we cannot be surprised that there is COVID19 in schools. However, we want the case rate in schools to stay the same (or less, which we are seeing in Texas) compared to the community. We do NOT want schools to become hot spots and have MORE cases than the surrounding community. So far, it doesn’t look like schools are hotspots, as kid trends closely reflect adult trends.

ALTHOUGH, the recent September uptick in cases overall (kids and adults) needs to be monitored closely. We don’t know the direction of transmission yet. In other words, is the Sept uptick due to school spread and kids giving it to adults OR is the Sept uptick due to community spread and adults giving it to kids? Or is this uptick not an uptick and just a random circumstance (ie not meaningful)? This is a difficult (but important) question to answer.

Remember….Because we lack a coordinated, national COVID19 response, we have to rely on county metrics to make decisions. There cannot be national blanket decisions. If your community has <10% TPR AND <10 new cases per 100,000 we can safely open schools. If this is not the case, schools can increase transmission risk in communities where transmission rates are high.

Love, YLE

Data Source: Leeb RT, Price S, Sliwa S, et al. COVID-19 Trends Among School-Aged Children — United States, March 1–September 19, 2020. MMWR Morb Mortal Wkly Rep. ePub: 28 September 2020. DOI: icon


COVID19 and pregnancy

Pregnancy has been consistently listed as a type II risk factor for COVID19. That is, pregnant women “might be at an increased risk for severe illness” but we aren’t sure because there is not enough evidence. Being pregnant myself during this entire pandemic, I’ve been following the evidence closely. Not much has come out yet to sway my opinion either way. 

However, two days ago, scientists published an MMWR article regarding this important topic.  

They used the COVID-NET surveillance database. This is a database of COVID19 related hospitalizations in 14 states (99 counties). During March 1-August 22, there were 598 pregnant patients in the registry (out of 7895 hospitalized women in the same age category): 2% were in 1st trimester; 10% in 2nd; and 87% in 3rd trimester (this DOES include those that were hospitalized because of labor and delivery).

What did they find?

  • 1 in 4 women (aged 15-49) hospitalized were pregnant (compared to 5% of women in the general population are pregnant at any given time)
  • 46% were symptomatic at hospital admission (1st and 2nd trimester were more likely to be asymptomatic than 3rd trimester)
  • Of the symptomatic patients, 16% went to the ICU and 9% required ventilation. There were 2 deaths
  • Preterm delivery was reported for 23% symptomatic women (which is higher than the general population= 10%) and 8% asymptomatic women 
  • 2 babies died, both of which were born to symptomatic women who required ventilation 

Translation: Severe illness and adverse birth outcomes were observed among pregnant women with COVID19. Pregnant women should especially be careful during this time: avoid close contact with persons with confirmed or suspected COVID-19, maintain 6 feet of distance from non-household members, and take general COVID-19 preventive measures, including wearing masks and practicing hand hygiene.

Hang in there, mamas.

Love, YLE 

Data Source: Delahoy MJ, Whitaker M, O’Halloran A, et al. Characteristics and Maternal and Birth Outcomes of Hospitalized Pregnant Women with Laboratory-Confirmed COVID-19 — COVID-NET, 13 States, March 1–August 22, 2020. MMWR Morb Mortal Wkly Rep. ePub: 16 September 2020.

Also, here is the list of high risk conditions for COVID19:

Children Hospitalizations

COVID19 vs. the flu among kiddos

We know that symptomatic COVID19 infections are rare among kids (compared to adults). However, there has yet to be a study comparing rates of hospitalizations, ICU admission, and ventilator use among kids with COVID19 compared to kids with the seasonal flu.

Yesterday, a paper was published in JAMA (highly reputable journal) comparing the two. Scientists used healthcare records from one pediatric hospital system in Washington, DC. They compared 315 kids diagnosed with COVID19 between March 25-May 15, 2020 to 1,402 kids diagnosed with the flu between October 1, 2019-June 6, 2020.

What did they find?

  • Kids with COVID19 had similar hospitalization rates (17% vs. 21%), similar ICU rates (6% vs. 7%), and similar ventilator use compared to kids with the flu (3% vs. 2%)  
  • Kids with COVID19 had more fevers, diarrhea/vomiting, headaches, body aches, and chest pain compared to kids with the flu
  • Among COVID19 hospitalizations, more kids were older than 15 years or had underlying medical conditions compared to flu hospitalizations
  • 0 kids were hospitalized with BOTH COVID19 and flu
  • 0 COVID19 deaths and 2 flu deaths

THIS is an interesting paper. It will be very useful for our clinicians (and maybe parents) this Fall to know how signs and symptoms may differ between the two respiratory infections. This can possibly help guide clinicians for the prompt identification and treatment of each.

This is also a beacon of good news for our kids and COVID19! But, it’s important to note that we still don’t know a lot about COVID19 among kids, like long-term outcomes and transmission rates from kid-to-kid and kid-to-adult. So proceed with caution.

It’s also important to note that we have a flu vaccine (hint, hint). Our hope is that more kids (and adults) will get it this year so we can avoid trying to differentiate and diagnose the two diseases at the same time.

Love, YLE

Data Source:

Antibodies Children GA Innovative Solutions National changes Social Distancing


Buckle up. In true 2020 fashion, several scientific developments popped up while I was on vacation…

1. Teachers’ and parents’ risk for severe COVID19

• 2.95 million teachers (50.6%) have risk factors for severe COVID19. This is mostly driven by obesity or heart conditions

• 37.7 million adults living with school-aged children (54%) have risk factors for severe COVID19. This is mostly driven by age, heart problems, or diabetes

• Risk is the same for those living with younger children compared to older children.

• So… what? “Without adequate safeguards, reopening schools could put millions of vulnerable adults at risk for severe COVID-19 illness”.

2. First global case of COVID19 re-infection

• In March, a 33-year-old man in Hong Kong was infected with COVID19. He had mild symptoms.

• Last week, he was infected with a different COVID19 strain and tested positive upon his arrival to Hong Kong from Spain. He is asymptomatic.


• After the first infection, he had no antibodies. But we already know that not everyone gets antibodies (especially mild symptoms; see my previous posts)

• After the second infection, he did produce antibodies. This is consistent with the immune system building stronger with each exposure to a pathogen, so second and third exposures may increase the chances to develop antibodies.

• In the words of immunologist Dr. Akiko Iwasaki, “This is no cause for alarm – this is a textbook example of how immunity should work.”

• Vaccination (and social distancing and masking) needs to be considered among people that have already been infected with COVID19

3. Wearing masks works (I feel like this is no duh, but in case you needed more ammunition)

• US states with high mask wearing compliance were more likely to have a R(t) less than 1 (control of community transmission)

• Mask wearing was higher among women, elderly, non-white or Hispanic, lower income people

• Mask wearing is highest along the coasts, southern border, and urban areas (see Figure)

• Mask wearing is even more important when (or if) social distancing is relaxed

4. Super-spreaders played a key role in MERS and Ebola. Their role in COVID19 was just revealed in Georgia:

• 2% of the population is responsible for 20% of infections• Super-spreaders likely explain major outbreaks in rural areas • Younger people are more likely to be super-spreaders

Love, YLE





Children Social Distancing Vaccine

Upcoming Flu and COVID19 Season

Flu season is around the corner. This, combined with COVID19, will have an impact on the health our community and capacity of our health systems.

Although COVID19 and influenza are vastly different pathogens, they do have areas of overlap:

• Both transmitted through respiratory droplets • Similar symptoms in the beginning

There are also drastic differences:

• COVID19 much more contagious than flu • COVID19 higher fatality rate (COVID19 IFR ~2.5 times- to 300 times deadlier than the flu, depending where you are in the globe; In the US, it’s 6.8 times deadlier than the flu) • Flu: most infectious AFTER symptoms; COVID19: most infectious BEFORE symptoms. • Flu: high risk for kids; COVID19: uncommon among kids or mild disease • Flu: Symptoms peak during 2-7 days; COVID19: symptoms peak 2-3 weeks • Flu: We have a vaccine; COVID19: no vaccine

Solomon et al., (2020). Influenza in the COVID-19 Era. JAMA.

So… what?

• Because both are spread through droplets, non-pharmaceutical interventions (masks, social distancing, movement restrictions) will be equally, if not more, important in the upcoming months.

• Flu vaccine is even more important to get this year. National coverage is lower than 50% in adults. We need to change this.

• No specific symptoms distinguish flu with COVID19, so it’s important for physicians to identify etiology

• Managing pediatric populations will differ depending on the virus

The strength of our collective public health response will directly influence morbidity and mortality this Fall. Do your part.

Love, YLE

Data Source: Solomon et al., (2020). Influenza in the COVID-19 Era. JAMA.