Lambda is cheap, API Gateway is expensive.
Lambda with API Gateway should be used for low or unpredictable volumes.
You can replace API Gateway by an ALB, which will be much much cheaper in the article use case.
Lambda is also great when it's triggered by everything but API Gateway. Analysing a file uploaded on S3, reacting to an SNS message or consuming messages in SQS.
Social security paid for 76% of all medical costs in 2014 (last numbers I could find).
92% of hospital bills
64% of doctors visits
62% of drugs, glasses and such. Most prescribed drugs by your doctor being reimbursed 100% you don't even have to pay at the pharmacy.
It's self-hosted.
The website seems down at the moment though.