Declining COVID-19 Case Fatality Rates across all ages: analysis of German data
Amidst the alarmist reports about continued rise in Covid cases in India, here’s a positive set of research findings. Analysis of German data shows that death rates (Case Fatality Rate or CFR) from Covid have been consistently declining. One of the explanations for that had been that as testing became more widespread, more and more milder cases were discovered boosting the denominator for the CFR. Also, as countries came out of lockdowns, more younger people who were out and about got infected boosting the denominator further without increasing the numerator. Data from Germany counters that as it shows that the CFR has declined across all age groups.
“Crude estimates of the CFR over time show that for people aged 80 and over the average CFR was 29% up to week 18, fell to 17% in weeks 19 to 27, and for mid-July onwards the CFR was 11% – a decrease of 61%.” A larger decrease is seen in the ages 60-79 with average CFR ~ 9% in March/April falling to 2% in July August.
…This analysis shows that the fatality rate from COVID-19 has declined in all age groups, and the older age groups drive the overall reduction.
Given German CFRs were low to start within the older age groups, it is likely in countries with higher CFRs at the outset, the effect could be more extensive.”
This could be useful to understand the situation in India too, amidst rising cases, death rates have consistently declined to now well below 2%. Some of the reasons that could be attributed: doctors have figured better methods of treatment (wider use of remdesvir, etc), increased healthcare capacity (makeshift covid care centres), lower viral loads as mask wearing has risen and possibly the virus itself losing virulence.