About two weeks back, World Health Organization launched the 'new Global Influenza Strategy for 2019-2030' with the aim of protecting people in all countries by promoting annual influenza vaccination as the most effective way to prevent the spread of influenza—a contagious respiratory illness commonly known as flu, caused by the spread of the influenza virus. The goal of the strategy, as mentioned on the organisation's website is to prevent seasonal influenza, control the spread of influenza from animals to humans, and prepare for the next influenza pandemic.
“The threat of pandemic influenza is ever-present,” said WHO Director General Dr Tedros Adhanom Ghebreyesus. “The on-going risk of a new influenza virus transmitting from animals to humans and potentially causing a pandemic is real. The question is not if we will have another pandemic, but when. We must be vigilant and prepared—the cost of a major influenza outbreak will far outweigh the price of prevention.”
According to WHO, the new strategy is the most comprehensive and far-reaching one that it has ever developed for influenza. It has two overarching goals: first is to call every country to have a tailored influenza programme in order to build stronger capacities for disease surveillance, response, prevention and control, second is to develop better tools to prevent, detect, control and treat influenza, such as more effective vaccines, antivirals and treatments.
“Since January 2019, the influenza vaccine is no more an optional vaccine but is compulsory for influenza virus now according to the XX vaccination schedule," says Dr Amol Annadate, paediatrician and neonatologist practicing in Aurangabad in Maharashtra. Influenza vaccines need to be taken every year, by both children as well as adults, as the influenza viruses constantly evolve.
Every year in February/March experts from WHO meet and review the precise influenza strains to include in the forthcoming season's (such as monsoons in India) vaccine to be used in the northen and southern hemispheres. The vaccines to be used in the northen hemisphere is marked as 'NH' on the labels while that to be used in the southern hemisphere is marked as 'SH.' However, in India, the doctors seldom pay attention to the kind of vaccine strain they administer to their patients, says Dr Annadate. "There is a serious lack of awareness among doctors, especially paediatricians in India when it comes to using the right type of influenza vaccine, meant for India, or particularly for countries that fall in the southern hemisphere. It used to be clearly mentioned on the vaccine if its a northern hemisphere strain or a southern hemisphere strain. However, nowadays, these vaccines come with labels where this distinction is not mentioned and doctors take no pain to ask or even bother."
Every year, the composition of influenza vaccines is modified separately by WHO for the northern and southern hemispheres. According to WHO, “since the antigenic changes in circulating influenza viruses can occur abruptly and at different times of the year, there may be significant differences between prevailing influenza strains in the northern and southern hemispheres. The composition of vaccines is adjusted for the hemisphere in which the vaccine will be used. Thus, a vaccine obtainable in one hemisphere may offer only partial protection against influenza infection in the other hemisphere, although in some years the viruses in the northern and southern vaccines may be antigenically identical.” This happened last in the year 2017, says Dr Annadate.
"India is categorised for the influenza vaccine in the southern hemisphere vaccination zone but today many vaccines we are using are northen hemisphere strains. Some companies such as the one I know in Ahmedabad are producing the influenza vaccine but aren't mentioning the type of strain on the labels. So I think we should compel the vendors, distributors and the doctors to ask the manufacturers to mention the strain clearly so that we know it, else we will not purchase these vaccines. If we paediatricians start rejecting these vaccines where NH or SH is not clearly mentioned on the label, obviously the production will go down," adds Dr Annadate who appeals to his fraternity by way of a video which he has circulated on social media too.