At Avian Flu Talk forum, General Discussion, the thread 'Was the 1889-1896 "Russian Flu" Corona Related?' makes an intriguing connection to international espionage via James Cantlie. In the thread, there is
'Bovine coronavirus and human coronavirus OC43 indicated that they had a most recent common ancestor in the late 19th century.'
Further on in that thread:
'Or take the doctor, James Cantlie, who gave the earliest description of the disease in the British Medical Journal magazine....Interestingly, the 1888 outbreak appears to have started in south China, a breeding ground for bat viruses that also harbor the SARS virus, Cantlie's description shows. The following year the disease progressed: from a tropical fever with spots, to a disease "in many cases with many more lung problems," said Cantlie. That was the form in which the disease swept across the world.'
James Cantlie
en.wikipedia.org
'....One of his first pupils at the college was the future Chinese leader, Sun Yat-sen....In 1896, poor health -- related to his unstinting work as a researcher and practicing physician -- forced Cantlie to return to London. Later that year, Dr. Sun visited him and was kidnapped by the Imperial Chinese secret service.'
The OC43 strain was mentioned in this thread on 3 Feb 2020, post #231, and in post #846, began the investigative trajectory for the Bos taurus COVID-19 link:
'We concluded that Bovidae and Cricetidae ACE2 could associate with SARS-CoV-2.'
One can see that chloroquine is effective against OC43:
OC43 / Chloroquine
Until recently, human coronaviruses (HCoVs), such as HCoV strain OC43 (HCoV-OC43), were mainly known to cause 15 to 30% of mild upper respiratory tract infections. In recent years, the identification of new HCoVs, including severe acute respiratory syndrome coronavirus, revealed that HCoVs can...
www.ncbi.nlm.nih.gov
'....A lethal HCoV-OC43 infection in newborn C57BL/6 mice can be treated with chloroquine acquired transplacentally or via maternal milk
