This year marks the 100th anniversary of one of the largest public health crises in modern history – the 1918 influenza pandemic known as the ‘Spanish flu’.
This pandemic reminded the globe that infectious diseases can be devastating, having affected 500 million people, and by the time it subsided in 1920, tens of millions of people are thought to have died.
Every year, countries are affected by annual seasonal influenza epidemics, whereby five to 15 per cent of the population are affected with upper respiratory tract infections. Hospitalisation and deaths mainly occur in high-risk groups, such as the elderly and chronically ill. These annual epidemics are thought to result in between three and five million cases of severe illness and between 250,000 and 500,000 deaths annually worldwide.
The epidemiology of influenza in Malta is monitored through the ‘Influenza’ surveillance, where a number of doctors practising in the community send a weekly report with the number of patients seen with flu-like symptoms, as well as the total number of consultations seen daily.
This rate is extrapolated to the general population to provide an overview of the community prevalence of influenza. Random swabs are also taken to identify the prevalent influenza types. Data is submitted to the European Centre for Disease Prevention and Control to contribute to the European surveillance.
In the 2017-2018 influenza season, there was a steady rise of cases of influenza-like illness from October 2017 up to a high peak in the second week of January 2018 at a rate of 166 cases per 1,000 population, with a downward slope by the first week of April.
The government has procured 100,000 vaccine doses to be provided free of charge. Vaccination started on October 15. For the first two weeks, specific workers and vulnerable groups are eligible
Vaccination is the best way to prevent influenza. While vaccine effectiveness can vary, recent studies show that flu vaccination reduces the risk of flu illness by between 40 and 60 per cent among the overall population during seasons when most circulating flu viruses are well-matched to the flu vaccine.
Older people with weaker immune systems often have a lower protective immune response after flu vaccination compared to younger, healthier people. Although immune responses may be lower in the elderly, vaccine effectiveness has been similar in most flu seasons among older adults and those with chronic health conditions, compared to younger, healthy adults. Hence, it is still recommended that the best way to protect the elderly is through vaccination.
Vaccination has consistently been found to provide a similar level of protection against flu illness in children to that seen among healthy adults. In one study, flu vaccine effectiveness was higher among children who received two doses of the flu vaccine in the first season they were vaccinated when compared to ‘partially vaccinated’ children who only received a single dose of flu vaccine. However, the partially vaccinated children still received some protection.
At least two factors play an important role in determining the likelihood that the flu vaccine will protect a person from the flu. One is the characteristics of the person being vaccinated, such as their age and health, while the other is the similarity or ‘match’ between the flu viruses the flu vaccine is designed to protect against and the flu viruses spreading in the community. Studies have supported the conclusion that flu vaccination benefits public health, especially when the flu vaccine is well matched to circulating flu viruses. Each year, the composition of the vaccine is updated to reflect the predicted circulating types. The WHO has recommended the composition of trivalent influenza virus vaccines for the Northern Hemisphere 2018-2019 influenza season to be the following: A/Michigan/45/2015 (H1N1) pdm09-like virus; A/Singapore/INFIMH-16-0019/2016-like virus; and B/Colorado/06/2017-like virus [B/Victoria/2/87 lineage].
The government has procured 100,000 vaccine doses to be provided free of charge. Vaccination started on October 15. For the first two weeks, specific workers and vulnerable groups are eligible. These include those residing in institutions; students attending special schools; those aged 55 and over; children aged six months to 59 months and those of any age suffering from chronic respiratory, heart, liver and kidney disease; and those with diabetes and chronic immunodeficiencies, including HIV and AIDS.
Vaccination in health centres is possible until October 27 – Monday to Friday between 8am and 1pm and from 8am to noon on Saturdays.
The Mosta, Paola and Floriana health centres are also open Monday to Saturday between 2.30pm and 7.30pm.
After October 27, vaccination remains available to all from the national immunisation clinics (normal opening schedules) and from the health centres’ treatment rooms.
Dr Charmaine Gauci is Superintendent of Public Health.