On: COVID-19
Episode: 97
Date: March 2020
Background: Scientist, pediatrician, and advocate in the fields of global health, vaccinology, and neglected tropical disease control.
Key Subjects:
- COVID-19.
- One of three 21st century coronavirus pandemics:
- SARS (2003), MERS (2012), COVID-19 (now).
- SARS-CoV2 is the virus; COVID-19 is the disease which that virus spreads.
- One of three 21st century coronavirus pandemics:
- “Perfect Storm” impact of COVID-19:
- High in fatality and spreads fast.
- SARS & MERS were higher in fatality, but didn’t spread as much.
- Many get the virus but don’t get sick –> keep walking around and spreading the virus -> reaches more vulnerable groups.
- Elderly (>70 years old).
- Underlying conditions (heart disease, diabetes, hypertension).
- Healthcare system overloaded.
- Concentrated,high inflow into a system that doesn’t have a lot of spare capacity to begin with.
- Healthcare workers and first responders are among the infected, further reducing capacity.
- Regardless of age of healthcare workers.
- Some evidence that they contract more severe versions of the virus.
- 15% of healthcare workers infected in Wuhan became ill.
- High in fatality and spreads fast.
- US may have missed the boat on early intervention (testing).
- Need to identify communities with significant levels of transmission and take action prior to cases ramping up.
- Convalescent plasma coronavirus therapy being tested as low-cost stop-gap solution.
- Taking antibodies from individuals that have been infected and have since recovered.
- Vaccine development time-line much longer.
- Trials need to clear very high approval thresholds given that you are looking to immunize healthy individuals.
- Hotez team has developed potential vaccine but has no funding for clinical trials.
Comments
- The podcast mentions the potential impact of weather conditions on transmission of the virus.
- In other words, could warmer weather slow down transmission?
- Some studies on the impact of weather condition on the transmission of SARS in Hong Kong in 2003 (here and here) seem to indicate that:
- the ideal temperature range for transmission was 16-28 degrees Celsius.
- during days with lower temperatures the risk of transmission may have been higher.
- The SARS outbreak in Hong Kong was fairly concentrated in time.
- Start to finish was a little over three months.
- While the weather conditions varied, temperature on average was mostly within the range indicated above.
- The graphs below are based on Hong Kong government data that I kept track of at the time (all information is for Hong Kong region only).
- The number of daily active cases (defined as: existing cases plus new cases less discharged cases less fatalities):
- The number of new cases and daily mean temperature (degrees in Celsius):