Daily COVID-19 Briefing: 4/4/20

Top news, reports and insights for today:

1. U.S. Cases rise by just just 13%, so where are the next hot spots?
   On Friday, just over 32,000 cases were added, a 1-day rise of just 13%. Cases are now doubling every 5 days. I don’t know yet whether this is a slow down in the actual epidemic or whether we have hit the limits of how fast we are testing. California still has 60,000 samples waiting to be tested and 45 states aren’t reporting “pending” tests. While New York continues to lead the nation with over 113,000 confirmed COVID-19 cases, the overall fraction of U.S. cases there continues to fall, sitting currently at 38%. New York logged an 11% rise in cases on Friday. Other states recording big jumps were New Mexico (+23%), Alabama (+20%), Connecticut (+29%), and Pennsylvania (+20%). The graph below shows the total accumulated cases by state. There are 7 states at or near 10,000 cases including California, Michigan, Florida, Louisiana, Massachussetts, New Jersey and New York. These are the states that are already on our radar screens. But, remembering that we are usually a few days behind in this epidemic, these numbers don’t tell us where the next hot spots are likely to be. For that, take a look at the next graph, which shows growth in new cases over the past 3 days as a percentage of total cases. This graph shows a different story. There are 21 states that have seen 50% growth or more in the last three days. Five states have seen 70% growth including Pennsylvania, Louisiana, South Dakota, Oklahoma, and Idaho.
   What does this mean? As all eyes focus on coastal states like California, New York and New Jersey, the next hot spots are likely going to be in the Midwest and South, where 13 of 26 states have seen recent rises of 50% or more. Idaho and Louisiana are top contenders for the next epicenters of the outbreak. Other states to watch include Michigan, Nebraska, Oklahoma, South Dakota, Alabama and Texas.

2. The CDC continues to get it wrong on symptoms
   A friend of mine just texted to say she was feeling badly and had a tele-visit with her doctor. She said her symptoms were not “COVID related”. When I asked her why, she said she didn’t have the “classic” symptoms, no fever and no respiratory symptoms. She did have a loss of appetite, chills, fatigue and body aches. The epidemiologist in me wants to scream when I hear this. As the Top-pick-of-the-day article points out, the messaging around the symptoms of COVID-19 remains confused and problematic. In my opinion, the CDC has done some things well and other things have been mishandled. That is to be expected when tackling a new disease. One area that is particularly worth discussing is case definition based on symptoms. At this moment, the CDC website still lists the same three symptoms: fever, cough and shortness of breath. This is a big problem. That was based on a study of just 44 patients in China very early in the outbreak. That list should have been ditched long ago. We now have plenty of better data that shows that there are more than a dozen symptoms that should be considered. Take a look at version 6 of my own COVID-19 Symptom Checklist. The SARS-CoV-2 virus impacts different people in different ways depending on age, time since infection, risk factors, genetics and a host of things we are just learning about. As many of 1-in-5 infected persons don’t have a fever. One-third of patients have gastrointestinal symptoms rather than respiratory ones. Fatigue is much more common than shortness of breath (especially early on). Some less common symptoms may be especially useful for identifying COVID-19, like pink eye, loss of sense of smell or taste, and stomach problems. Other symptoms may be especially good for predicting who is going to have very severe disease (like sudden confusion or chest pains).
   Why this matters? There are probably tens of thousands of Americans who have COVID-19 but think they don’t because they don’t have fever, cough and shortness of breath. Those people are not considering themselves infected and are probably infecting others for that reason. We can and must do better on case definition.

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Daily COVID-19 Briefing: 4/2/20

Top news, reports and insights for today:

1. U.S. deaths resume rapid doubling rate
   We are back to looking at the epidemiologic curve for deaths after Washington State and California have resumed timely COVID-19 reporting. The graph below shows that after a few days of flattened growth in deaths, the outlook has darkened; growth in deaths has returned to a rapid pace, doubling every 2-3 days. On Wednesday, a record 940 deaths were recorded. Notable rises in deaths were seen in numerous states including Nevada (+51%), Illinois (+42%), Minnesota (+40%), Wisconsin (+48%), Texas (+41%), Massachussetts (+37+), Maryland (+70%), New Jersey (+33%), and Pennsylvania (+54%).
   What it means? The pace of COVID-19 deaths tells us that the White House prediction about April being a difficult month is likely to be correct. At this pace, the U.S. may be facing several thousand deaths every day as soon as the end of next week. The crude fatality ratio in the U.S. rose from 1.9% over the weekend to 2.4% as of this moment. This number must be interpreted in the context of a severe undercount of mild and asymptomatic cases, but it suggests the possibility that the health sector is under considerable stress. This pattern looks similar to what we have seen in Italy. If hospitals continue to run out of supplies and ventilators, and staff continue to get infected, the death rate will rise in the U.S..

2. The FDA authorizes first coronavirus antibody test: a game changer?
   CNN and others report today that the Food and Drug Administration (FDA) has issued an emergency use authorization for a coronavirus test that can determine the presence of antibodies to SARS-CoV-2. This potentially game-changing test would improve our ability to determine who has been exposed to the virus and who is “immune” to further infection. The new test, from Cellex Inc. requires a blood sample taken from a vein in the arm rather than the current test, which is based on detecting the actual virus in a sample of nasal or oral secretions. This test will not replace viral detection, but will bring a new tool to the arsenal. It is critical to understand that much is not yet well understood about the timeline of how the body makes antibodies in response to infection with this virus. It is not yet known how long after infection antibodies can be detected or how long after symptoms subside that the test will be accurate. It’s also unknown how rapidly the company (or others) will be able to scale up production and distribution. Earlier rumors that the FDA was ready to approve a test that could be done in minutes from a finger prick proved false.
   What this means? We must be patient and cautious about this development. Eventually, the benefit of this type of test would be to offload pressure on the standard testing system. More important, the ability to identify which medical workers are “immune” would help hospitals by determining who can work safely with sick patients.
   
3. We don’t know how many tests are pending, so we don’t know how many cases we have
   Yesterday, I shined a spot light on the problems in testing in California. As of today’s numbers, California has results for 30,000 tests done, but another 57,400 tests are in testing limbo. If the same fraction of tests are positive, then California has 23,800 cases, not the 8,155 they are reporting. California may have 3 times more COVID-19 infections than we are now counting. And that only deals with the tests that have already been performed, let alone the huge numbers that have never been tested. Today, I ask what we know about “pending” tests in other states. The best data I can find is by the COVID Tracking Project. As of today, their state-by-state tally gives us information on the number of pending tests for only 5 states and Puerto Rico. There is no information for the other 46 states and DC. The good news is that the fraction of pending tests is pretty low in Florida (2%), Hawaii (0.2%), Nebraska (0.2%), and New Hampshire (2%). Puerto Rico, in contrast, has over 1,000 pending tests (37%). Data on testing is getting harder, not easier to get nationally. Some states have started and stopping the reporting of negative results. The shift to private labs has taken the CDC out of the loop in tracking testing. The graph below was clipped from the CDC website today. It shows a couple of things: 1) The CDC’s own labs are playing no significant role in US testing and have completely disappeared after March 13; 2) US public health labs appear to have reached their peak testing capacity of about 8,500 tests per day around the middle of March. If there was more surge capacity in testing, we would have seen a continued increase, but we don’t. Of course, the private labs are not shown.
   What does this mean? Currently we have no idea how extensive the backlog of tests seen in California is across the nation. If we are to get a handle of the course of this epidemic, private and government labs must begin systematic reporting of pending tests.

Screen capture of testing data from CDC taken April 2, 2020 from: https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/testing-in-us.html

Daily COVID-19 Briefing: 3/19/20

1. Sharp increases in U.S. cases, testing lags dramatically behind other countries
   New case reports in the U.S. for March 18 demonstrate dramatic rises.  Cases doubled overnight.  The most important thing to understand is that this rise is expected and does not yet provide a good picture of the extent of the epidemic.  Cases are rising exponentially because testing is rising exponentially.  It is not possible to predict a peak in the US right now.  Using China or Italy as a guide is inappropriate because by the equivalent point in the epidemic, both countries had tested a much higher proportion of patients.  
   To put this issue into perspective, I made the graph below.  It shows how well countries are doing at testing their populations.  These analyses are crude because the data is not great. I found a useful data source from OurWorldInData.org linking the best numbers we have for total tests done as a population rate (tests / 100,000 population).  These results are striking.  Countries like Kuwait, the United Arab Emirates, South Korea, and Italy have now tested 200 per 100,000 or more.  
   What does this mean?  To make sense of the U.S. numbers, take note of the fact that while there have been 41,000+ tests, this country ranks dead lastin terms of testing per capita.  Italy has now tested 20 times the fraction of its people than U.S. has. Until this country catches up, we will continue to see rapidly doubling case totals, and we will not yet be able to tell the true burden of this epidemic.

2. California in “lockdown”
   Gov. Gavin Newsom ordered all California residents to stay home, placing restrictions on 40 million residents. This marks the first mandatory restrictions placed on all residents of a state to fight against the novel coronavirus. This unprecedented step is the most far-reaching directive issued thus far. The mandatory order allows Californians to continue to visit gas stations, pharmacies, grocery stores, food banks, banks and laundromats. This new directive was motivated in part by a stark briefing the Governor received, which forecasts 25.5 million residents will become infected in the next 8 weeks (more than half of the state).
   What does it mean? Yesterday California added 126 new cases (+28%) while more cases were added by Washington (175), New Jersey (162) and New York (1008). It is likely that similar state-wide restrictions will be forthcoming in other states.
3. Young people may be at more risk than we thought
   A report just released by the CDC details lessons learned from the first 2,500 cases in the U.S. One surprising finding was that the COVID-19 epidemic seems to be hitting young people harder in the U.S. than has been seen in China. While it is true in the U.S. and in China that older adults are at greater risk of severe symptoms and death, the fraction of cases among younger adults was surprisingly high. In the U.S., 29% of cases were aged 20-44 and 5% were in persons aged 0-19 years. Among cases that were hospitalized, 20% were 20-44 years old. Of the 121 patients admitted to ICU, 12% were aged 20-44.
   What does this mean? The belief that younger people are safe from becoming sick remains widespread. This has contributed to startling images of college students partying with abandon on spring break. While these data are preliminary, they do show that young people are experiencing significant illness requiring hospitalization and advanced care.

– UPDATED 3/20/20 at 3:13 am