The year-end and the yuletide season will be soon upon us. Ordinarily we would be gearing to go travelling and some of us would be headed to cold temperatures in the northern part of the globe. However, this has been anything but an ordinary year. We have been beset by a once-in-a-centenary event of a pandemic. As we speak, the pandemic has claimed its one millionth victim and shows no signs of abating. We are all resigned to tracking with bated breath the progress of the 11 Covid-19 vaccines in Phase 3 human trials as there seems to be no other way to stop the onslaught of the coronavirus. Yet we should not be so helpless; we can still do our part by getting our influenza (flu) vaccines. The influenza vaccine is important at this juncture in our fight against the pandemic.
We should first understand that influenza attacks vulnerable groups especially in winter. We do not have a winter season but up to recently we have had a mobile population that travelled extensively for leisure and business; and we used to have 20 million visitors annually. Despite being at the Equator and having tropical climate, we are also an air-conditioned nation. All these factors can make us more susceptible to influenza and its spread. The more vulnerable among us include young children, those who are pregnant and seniors, especially those with chronic diseases and ailments.
Risk to vulnerable groups
Influenza vaccines are recommended for these groups and in the midst of the pandemic, it is imperative that we get them vaccinated to avoid the difficulty of telling apart the Covid-19 infection from the common cold or influenza when patients present with respiratory illnesses. We can also prevent hospitalisation or events related to flu that may increase the risk of the vulnerable groups to Covid-19. We are often asked which flu vaccine we need to take. There are two flu vaccines in a calendar year. The Northern Hemisphere vaccine is available around this time of the year while the Southern Hemisphere vaccine is available in March. The names of Northern and Southern refer to the winter seasons that are critical to patients who contract influenza. The winter season tends to exacerbate the influenza and lead to complications and ultimately the demise of the vulnerable patients. As a result we tend to vaccinate prior to the arrival of winter.
We also need to understand the logistics of producing a flu vaccine. The initial research is to figure out what flu strains will be active in the winter ahead. This involves some degree of “crystal balling” to identify the strains the vaccine should be effective against. Sometimes the prediction is correct and sometimes it is not. It takes, on an average, five months for the pharmaceutical firms to produce, ship and have a vaccine made available. We will usually offer the vaccine that is currently available. Sometimes because the pharmaceutical firms have to make an educated guess as to which flu strains will be causing problems in the winter ahead, we have a situation where if one takes the prevailing vaccine, there is still a chance that we have to take the next vaccine that comes out six months later. So you may hear of people taking two flu vaccines within six months of each other. Fortunately we have guidance on this from our Ministry of Health.
While we are in the midst of a pandemic, we should look back at history. We had the infamous Spanish flu pandemic in 1918 that spawned the H1N1 virus that came from birds. There were smaller pandemics in 1957 (H2N2), 1968 (H3N2) and the recent H1N1 in 2009. I was fascinated by the stories of scientists who discovered the genome of the Spanish flu by exhuming the bodies of Inuit natives who died in 1918. The lung tissue of these bodies was well preserved by the permafrost in Alaska. The scientists managed to extract the RNA of the virus from the preserved lung tissue, decipher it and reconstruct the actual virus at the CDC Laboratories in Atlanta, Georgia. As for the 1957 flu pandemic, my Italian patient in his 70s recall contracting the flu in 1957 as a young boy and told me that he was so ill that he was in bed for three weeks.
We are always faced with mutating flu strains and the latest is a swine flu strain in China. This strain is H1N1 and has been spreading since 2016 in the Chinese pig herd. They have found that about 10 per cent of swine workers have been exposed to the virus. So far there has been no human-to-human spread but the local and global authorities are watching this virus like a hawk. This siege is the reality in our global and united fight against viral threats. One of the key battles is the speed of a vaccine against a novel virus. The vaccines take a long time to be produced and in the H1N1 pandemic in 2009, it took 26 weeks for a vaccine to be produced and shipped. We can technically reduce this lead time to 12 weeks but that will need a lot of resources and international cooperation.
A universal flu vaccine is still light years away. The comparison is the ongoing vaccine race for the Covid-19 vaccine. We had the published genome of the Covid-19 virus on the weekend of Jan 11/12 this year. As of today we have 11 vaccines in Phase 3 trials and five approved for limited use. These five include four Chinese vaccines and one Russian vaccine. In the midst of this pandemic while we wait for the Covid-19 vaccine, we must act and mobilise the population to get vaccinated against influenza. The latest flu vaccine is now here and I myself have taken it. While the use of face masks has reduced the incidence of influenza, it is still a good idea to approach your family doctor for a flu shot for all the reasons I have outlined above.
One reason is that it can help in differentiating the Covid-19 infection from the common cold or influenza when patients show symptoms of respiratory illnesses.