Analysis: without effective vaccines, the flu epidemic 70 years ago caused many deaths, closed schools and impacted businesses

We have all become very familiar with terms such as pandemic, epidemic, quarantine, infectious disease, social distancing, close contact, antibodies, PCR testing and a host of other words most people had to Google to understand before March 2020. Just yesterday, my seven-year old daughter told me that two of her classmates could not make it to school because "they had symptoms". Our lives have been turned upside down.

However, our coronavirus experience is not unique. Until the 1960s, epidemics were widespread in Ireland and affected thousands of people of all ages. Influenza, measles, poliomyelitis, rubella, tuberculosis and whooping cough are examples of infectious diseases that were widely circulating in Ireland.

Almost every year, there was an epidemic or an outbreak of one these diseases. For example, 6,795 cases of tuberculosis and 4,364 cases of whooping cough were recorded in 1952 and a total of 4,867 cases of rubella and 499 cases of poliomyelitis were recorded in 1956. Three years later, 15,134 cases of measles were recorded. Dublin had the highest rate of disease, but all parts of Ireland were affected.


From RTÉ Radio 1's News A One, historian Dan Snow on the lesssons from past pandemics

In the 1950s, infant mortality was declining rapidly and it was much lower than in the 1930s or in the 1940s. In 1935, the infant mortality rate was 68 (for every 1,000 babies born alive, 68 died before reaching one year of age) which compares to a rate of 37 in 1955. The infant mortality rate is currently 2.8.

Infectious diseases were still responsible for the deaths of many infants in the 1950s. In 1955 alone, a total of 403 infants died because they contracted whooping cough, influenza or another respiratory disease. It is only after the introduction of vaccines against specific diseases that cases and deaths started to fall dramatically.

In 1951, Ireland experienced an influenza epidemic. Two physicians, Patrick Meenan and M. Clarke, documented this epidemic in an article published in the Journal of the Irish Medical Association. At the time, Meenan and Clarke were working in the WHO Influenza Centre, in Dublin's St Vincent's Hospital. Meenan subsequently became the Dean of the Faculty of Medicine at University College Dublin and president of the Medical Council of Ireland.

From British Pathé, 1940s public health advice for those with flu symptoms

Meenan and Clarke explained very carefully the route that the influenza epidemic took to reach Ireland. The first outbreak was reported in Sweden in June 1950 and the epidemic affected most countries in Europe. In November of the same year, an outbreak was reported in northern Sweden and in two neighbouring countries Denmark and Norway. In December, the outbreak spread to Finland, Germany and the Netherlands and reached England in the middle of that month, appearing at the same time in Newcastle and Liverpool.

During Christmas week, it reached Belfast and Kerry. By the end of December, it became clear that that a countrywide epidemic was unavoidable in Ireland and it took about six weeks for the virus to reach most parts of Ireland. The general pattern was one of spread by "continuity of district", which means that the disease did spread from one area of the country to neighbouring areas. At the end of December, all County Medical Officers of Health were informed and asked for their co-operation.

Many schools had to close to limit the spread of the disease. For example, most schools had to close in Mayo in early February. A total of 72 national schools closed in Clare. In Westmeath, 14 schools closed in the last two weeks of January. Almost all schools closed in Cork. The original plan was that schools in Cork would close for 10 days, but the closure was then extended for a further 10 day period.

Businesses were also affected. Evidence shows that a total of 262 employees of a large firm in Dublin were affected in the peak week, 111 of them on one day. A smaller firm reported that around one in five of their employees were affected in the successive weeks.

The main difference between now and 1951 is that vaccines that are working have been specifically developed

The number of deaths from influenza during 1951 were recorded at 2,399, the highest number recorded since 1937, with 1,934 deaths occurring between January and March 1951. The deaths occurred mainly among people over the age of 65. However, a few deaths amongst young adults were also reported. The death rate from influenza in 1951 was 81 per 100,000 population, which compares to a rate of 9.4 deaths from influenza per 100,000 population in 1949. Evidence for Ireland suggests that the death rate from Covid-19 (so far) is about 111 per 100,000 population.

The similarities between the 1951 influenza epidemic and the Covid-19 pandemic are striking. They both reached here from abroad and have caused many deaths, especially among the older population. They have had a significant impact on people's daily life and have forced children to stay home from school.

However, there also important differences. The Covid-19 pandemic has been much longer in duration and has been deadlier - and it is not over yet. The main difference between now and 1951, though, is that vaccines that are working have been specifically developed. We have an effective tool to fight the spread and deadliness of Covid-19. People in 1951 were not so fortunate in this respect.
