​The CDC recently provided some updates regarding COVID 19.  These numbers address both how transmissible the virus is as well as the severity of infection.  Keep in mind that these numbers are estimates, and there’s definitely been quite a discrepancy between computer modeling and actual outcomes in the past, although there is now 6 months of data to base these estimates on that wasn’t available before.  That being said, here are the current numbers from the CDC website.

1. Basic reproduction number – this is the number of cases, on average, that result from spread of a single infected person.  The current best estimate is 2.5, meaning that for every one person infected, he/she will spread it to 2.5 others.  The projected range is from as low as 2 to as high as 4.  In more densely populated areas, this number would be expected to be higher than in areas with lower population density.  If immunity develops following infection, this number would decrease over time to the effective reproduction number, which would be lower.  At the present time, there is no data on how masks and social distancing play a role in affecting this number.
2. Infection fatality ratio – the number of deaths from infection divided by the number of people with the infection, regardless of whether or not they have symptoms.  For age 0-19:  0.003% (so survival rate is 99.997%);  for age 20-49:  0.02% (survival rate is 99.98%); for age 50-69:  0.5% (survival rate is 99.5%); and for age >70:  5.4% (survival rate is 94.6%).  There is a caveat for the last age range as the CDC states that the data is only likely accurate for those up to age 79, so there are not specific numbers for those 80 and older, and those less than 2 years old carry the highest risk in the pediatric age group, despite being grouped with those up to 19.  Also, it is important to remember that certain medical conditions may also affect a person’s risk beyond simply the age-related risk so that he/she may be more vulnerable than statics suggest.
3. Percentage of infections that are symptomatic – the current best estimate is 40%, although it may be as low as 10% or as high as 70%.
4. Infectiousness of asympomatic individuals – again, this statistic has large variability with 75% being the current best estimate but a range as low as 25% or as high as 100%.
5. Percentage of transmission occurring prior to onset of symptoms – it is currently projected that 50% of viral transmission happens before the infected person has symptoms.  The range may be as low as 30% or as high as 70%.

This information is definitely a lot of numbers to digest, but it seems to show a virus that is pretty easily spread, and there does also seem to an increased risk as one gets older.  While it looks like for many people, especially a younger population (with 419 deaths in the age range up to age 24 vs 643 deaths from influenza in patients up to just age 17 during the 2017-2018 flu season), medical comorbidities such as obesity, high blood pressure and chronic lung disease may increase that risk.  That being said, according an Oxfam report, over 100 million people worldwide may be pushed to the brink of starvation with hunger-related deaths from COVID 19-related food shortage reaching 12,000 per day (vs peak COVID deaths at 10,000 per day earlier this year), and this doesn’t take into account financial hardships from job loss due to economic shutdown.  This is a tough situation, both from the health effects of the virus as well as the socioeconomic impacts.  Fortunately, investigation continues into potential treatment options (for instance, a new ICAM protocol may have some promise) in addition to vaccination studies.  At the end of the day, the information is there for you to draw your own conclusions, so if you’d like to check out the information yourself, here’s the link to the CDC website used for the statistics above.  https://www.cdc.gov/coronavirus/2019-ncov/hcp/planning-scenarios.html  The numbers are in Table 1.

With such dramatic changes on many people’s lifestyle this year from all the societal changes initiated by Covid, a good night’s sleep has become one of the first casualties.  For some, newfound downtime during the day has led to increased napping and difficulty falling asleep at night.  For others, stress plays a big role in keeping them up late or making getting up in the morning tough.  The temptation is often to try taking a supplement rather than to change behavior (it’s easier to swallow a pill than ignore the siren call of the snooze button), and one of the most commonly used is melatonin.  Here we’ll take a look at what exactly melatonin is and how it works.

What is melatonin?  Melatonin is a hormone produced by the pineal gland (a tiny gland in the brain) that helps regulate the sleep-wake cycle.  Production of melatonin generally increases as darkness increases, which in turn, helps make us sleepy as night approaches.  Production is generally suppressed by light, so we tend to be more awake during the day.  That cycle of sleepy and wakeful is referred to as our circadian rhythm.
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How does melatonin work?  By signaling the body that it’s time to sleep, the thought is that it may help with insomnia or delayed sleep phase disorder (trouble falling asleep before 2 AM) as well as shift work disorder (those who work night shifts) and jet lag.  That being said, studies have shown mixed results with regards to efficacy.  Perhaps for those who are truly deficient, they may see more improvement of symptoms than those who are able to produce adequate amounts on their own, but for now, there doesn’t seem to be a way to determine which individuals would be most responsive to supplemental melatonin.

Is melatonin safe?  Generally, melatonin is considered relatively safe for short term use, i.e. 1-2 months, although long term safety information is limited.  There are certainly those who should avoid melatonin use such as those on blood thinners, diabetes medications, immunosuppressants, dementia medications, and even birth control pills because melatonin can affect the efficacy of these medications.  Also, use in children should be discussed with a pediatrician as there is a question of whether or not melatonin, as a hormone, can affect hormonal regulation of growth and even puberty or menstrual cycles in those with immature endocrine systems.  As for those who are pregnant or breastfeeding, there is no quality data regarding safety for use of melatonin.  Common side effects can include daytime sleepiness, anxiety, GI distress, dizziness and depression among others.  Because it is considered a supplement in the U.S. (rather than a drug, which would be managed by the FDA), safety and efficacy data is limited.  In fact, a study of melatonin supplements from a few years ago showed that the amount of melatonin listed on the bottle varied significantly from the amount actually in the product in most of those products evaluated, and around a quarter were contaminated by serotonin.

In the end, reviews of safety and efficacy are mixed for supplemental melatonin.  The American College of Physicians recommends cognitive behavioral therapy as a first-line treatment of insomnia.  As for simple changes to make on your own, limiting daytime naps, having consistent bedtimes and wake times, exercising regularly and avoiding electronics (especially those emitting blue light) for several hours before trying to sleep can all be good places to start.  Often, the hardest part of making these changes is avoiding the temptation to catch up on some missed sleep at night with naps during the day, but by being more tired when trying to fall asleep at night, resuming (or starting) a more regular sleep schedule can be within reach. 

Dr. Nick