A century ago, the Spanish influenza infected one-third of the world’s population and wiped out approximately 100 million people. It was the deadliest flu pandemic in history, the likes of which have not been seen again, but experts fear another massive deadly influenza pandemic is imminent.

In the decades since the Spanish flu struck millions, much progress has been made in flu preventative and treatment methods, yet there is still no effective universal vaccine or effective treatment for the most serious influenza infections.

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Why Is the Flu So Hard to Prevent and Treat?

There are many strains of influenza — and they are constantly evolving, as a result, finding effective solutions to fight back against the most serious infections has proven difficult. Flu viruses mutate and build defenses to treatment and vaccines over time — that’s why flu vaccines are administered annually and are typically only 40% to 60% effective at preventing the flu.

Still, health experts recommend getting vaccinated against the flu, as the vaccine helps prevent infection, reduces the severity of illness, and can save lives. Though influenza viruses are not always seen as high-risk infections, they can be both serious and fatal, and are considered one of the most feared threats to global health.

Read More: What Is Universal Health Coverage and How Can We Achieve It?

Who Is Susceptible to the Flu?

These viruses are highly contagious, part of what makes them so dangerous, and typically affect respiratory systems. This makes influenza viruses particularly dangerous for people with vulnerable immune systems, including children, pregnant women, and the elderly. People with medical conditions and compromised immune systems are also more susceptible to being infected by an influenza virus, but anyone can get the flu. 

At least 80,000 died of the flu or flu-related complications last winter in the United States, according to the Center for Disease Control and Prevention — the highest flu-related death toll the US has seen in approximately four decades. Experts attribute the unusually high number, in part, to last season’s flu vaccine, which was only 25% effective at preventing the most common strain of the flu.

Influenza viruses may be transmitted through the air, passed from person to person, or spread through direct contact with infected material.

What Can Be Done?

In order to prevent millions of flu-related deaths and protect the global community, more innovation is needed.

Johnson & Johnson is aiming to develop cutting-edge solutions through extensive research to prevent and treat the most severe viral respiratory infections and to help protect us against an international pandemic.