Second wave of the Spanish flu

On 27 August 1918 two or three sailors with fever and flu symptoms reported to the sick bay on Commonwealth Pier in Boston. The next day eight came, and the day after that several dozen. This is how the second wave of the pandemic, far more dangerous than the spring one, began in the United States. At almost the same time, in the second half of August, violent epidemics broke out in two other ports, thousands of kilometres apart: in Brest in France and in Freetown in the British colony of Sierra Leone.

Three ports

All three ports were linked by the war. Brest was the largest port at which American soldiers disembarked. According to some researchers it was there, among the Americans or French naval recruits, that the disease took on a new, dangerous form, and ships carried it onwards. Freetown was an important coaling port on the routes around Africa. On 15 August the armed merchant cruiser HMS Mantua arrived there with flu cases on board; she is considered one of the first ships to have brought the pandemic to Africa. The epidemic quickly engulfed the town and the ships in the roadstead. On the battleship HMS Africa, which lay in the port throughout September, 476 men were sick on the peak day, 9 September, and 51 died within the month.

Whether a single, more dangerous strain of the virus spread from one place to the three ports, or whether it appeared in several places at once, is still unknown. Researchers also disagree over whether it was a mutation or merely a stronger strain that had emerged during the spring wave.

Boston

Commonwealth Pier was a huge, crowded pier on which up to 7,000 sailors awaiting assignment lived in the “Receiving Ship” barracks. By the end of the week a hundred new patients were arriving every day, and according to some accounts a hundred and fifty. The more seriously ill were taken to the naval hospital at Chelsea across the harbour, but the disease soon spread beyond the base. On 3 September the first civilian case was recorded. In September the flu broke out at Camp Devens, a large army camp west of the city, where more than 12,000 cases were recorded within two weeks, and a hospital built for 2,000 beds had to take in four times as many patients. By the end of September nearly 50,000 people in Massachusetts had the flu. In the following weeks the epidemic engulfed the whole of the United States, and October 1918 was the deadliest month of the pandemic.

A different disease

In the spring the flu had been a nuisance but rarely killed. The armies felt it keenly: German companies at Hamel at the beginning of July numbered about fifty rifles each, and according to the German historian Eckard Michels, during the Second Battle of the Marne the flu put nearly 400,000 German soldiers out of the ranks. Most of the sick, however, returned to duty after a few days. The second wave was different. After a few days of fever some patients developed haemorrhagic pneumonia and turned blue from lack of oxygen, and death often came within a few days. According to the American researchers Jeffery Taubenberger and David Morens, the case fatality rate exceeded 2.5 per cent, whereas in other influenza pandemics it was below 0.1 per cent. Strangest of all was that those who died were above all young and healthy people aged 20–40, usually the most resistant to flu.

From September to November the second wave went round the whole world. It was spread by troopships, merchant ships and trains, and overcrowded camps, barracks and hospitals became its breeding grounds. According to the American CDC, about 500 million people, a third of the world’s population, fell ill during the whole pandemic, and at least 50 million died, most of them in the autumn of 1918.

In the Polish lands

In the Polish lands at the end of August the flu was still mild. On 24 August Gazeta Lekarska wrote that soldiers of the Polish Armed Forces in Garwolin and Ostrów Mazowiecka were ill, but no complications or deaths had been recorded. On 29 August Kurjer Warszawski published the explanations of a professor at the University of Warsaw, the bacteriologist Stanisław Serkowski, whose opinion on the “Spanish disease” the editors had requested. Serkowski rejected the prevailing view that influenza was caused by the bacterium described by Richard Pfeiffer, and suggested that its cause was germs invisible under the microscope, that is, viruses. He was right, although the influenza virus was not isolated until the 1930s. In September the second wave also reached Warsaw.