The enigma of the 1889 Russian flu pandemic: A coronavirus?

Abstract

The "Russian flu", which raged from 1889 to 1894, is considered as the first pandemic of the industrial era for which statistics have been collected. This planetary event started in Turkestan and hit the Russian Empire, before reaching all European countries, the United States of America, and the whole world. Contemporaries were surprised by its high contagiousness as evidenced by attack rates averaging 60% in urban populations, its rapid spread in successive waves circling the globe in a few months by rail and sea, and the tendency of the disease to relapse. Despite its low case-fatality rate (0.10%-0.28%), it is estimated to have caused one million deaths worldwide. On serological grounds, it is generally accepted that the causative agent of Russian influenza was Myxovirus influenzae, the virus identified for all influenza pandemics since the "Spanish flu" of 1918. In light of the Covid-19 pandemic, which has underscored the extraordinary epidemic potential of coronaviruses, this assumption has recently been questioned. Coronaviruses come from wild reservoirs (bats, rodents, birds, …). They induce respiratory symptoms mimicking influenza, possibly leading to respiratory distress with pneumonia. In addition to the Covid-19 pandemic, recent deadly and limited epidemics, such as SARS in 2002 and MERS in 2012, have occurred. Russian influenza presented as an influenza-like syndrome with clinical peculiarities (multivisceral and neurological involvement, skin rash, early iterative relapses), evoking some particularities of Covid-19. Four other coronaviruses circulating in the human population for decades (HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1) have been found to be responsible for 15 to 30% of seasonal colds. All of these viruses are of animal origin. Recently, phylogenetic studies have revealed the genetic proximity between a bovine coronavirus BCoV and the human virus HCoV-OC43, indicating that the latter emerged around 1890, at the time of the Russian flu, when an epizootic was raging among cattle throughout Europe. Could the current human virus be the attenuated remnant that appeared after the Russian flu in 1894? Was there a coronavirus pandemic before Covid-19 ?

Keywords: Coronavirus; Covid-19; HCoV-OC43; Influenza; Myxovirus influenzae; Pandemic; Pneumonia; Russian influenza; SARS-CoV2.

Fig. 1

Kinetics of the spread of Russian influenza in Europe in 1889–1890 (with the calendar). Red dots: cities hit by the pandemic (their size corresponds to the magnitude at the peak). Green dots: extinguished outbreaks (from AJ Valleron [17]).

Fig. 2

“Influenza in Paris”. The tent of the sick in the garden of the Beaujon Hospital. Le Petit Parisien (January 12, 1890)- The National Library of Medicine.

Fig. 3

Mortality of influenza from 1847 to 1905 in the United-Kingdom. Mortality reached 674/million in 1890, followed by several peaks up until the epidemic of 1900 (modified from [14,15]).

Fig. 4

Map of the distribution of the Russian influenza pandemic in Europe and the United States of America (from [1] p.65). Outbreaks are shown in red. Photo : Wellcome Collection Gallery, Creative Commons, London. Copyright: Copyrighted work available under Creative Commons Attribution only licence CC BY 4.0 http://creativecommons.org/licenses/by/4.0/.

Fig. 5

Mortality statistics during the Russian influenza in 1890 in Indiana (USA), showing a third wave associated with higher mortality (modified from [16]).

Fig. 6

Proportion at several ages to 100 deaths from influenza, comparing the period 1847–1889 to 1890 mortality (modified from [1]).

Fig. 7

The phylogenic tree of amino acid sequences of HCoV (OC43, NL63, 229E, HKU1) compared to the animal coronavirus (bovine BoCoV, porcine PHEV, PEDV,TGEV, murine MHV, avian IBV). The divergence between HCOV-OC43 occurred around 1890 (modified from [44]).

Fig. 8

Comparison of the waves of the flu pandemics since 1889 (modified from [47]).