As climate change boosts mosquito-borne diseases, we must take action to stop their spread

Global warming is increasingly visible all around us, despite 50 years of warnings. This has placed environmental sustainability at the top of the agenda for governments, industry leaders and the public.

While we work to mitigate the growing impact of drought, rising sea levels and extreme weather, we cannot lose sight of the underestimated consequence of the warming planet: the spread of debilitating and potentially deadly mosquito-borne diseases.

Dengue Fever, Zika, West Nile and Chikungunya, among others, are mosquito-borne diseases that have, until recently, primarily existed in warmer climates with higher levels of mosquito populations. But they are now expanding geographically, thanks to rising temperatures and sea levels creating new welcoming habitats for these insects. Mosquitos, being cold-blooded like all insects, thrive in warmer weather. As global warming leads to rising air and water temperatures and more rainfall and flooding, more environments are becoming suitable for mosquitos to multiply.

Dengue Fever, for example, has traditionally been confined to parts of Latin America and Southeast Asia, and while 50 years ago it was found in only nine countries, today it is prevalent in more than 125. The mosquito-borne disease causes an estimated 500,000 hospitalisations a year, putting a substantial burden on health systems.

There’s little doubt that the warming planet is a primary cause of the spread. A 2020 study by the US National Institute of Health concluded that, for every one degree Celsius the planet warms, Dengue Fever cases will increase by 35%. In fact, Dengue Fever has already increased by 30-fold over the past 50 years.

Meanwhile, Zika, a mosquito-borne disease that can cause microcephaly or other brain and developmental defects, rarely infected humans 50 years ago. Following the 2016 outbreak of Zika – which spread rapidly in the Americas – the disease continued to circulate and is now found in 86 countries.

If current trends continue, by the end of the century as many as 8.4 billion people – out of a projected population of 11.2 billion – could be at risk of contracting these diseases. The countries likely to be most severely impacted are the ones whose health systems struggled to withstand the COVID-19 pandemic. The United Nations Development Programme estimated that developing countries will lose at least $220 billion in income from COVID-19. They can’t take another setback, healthwise or financially.

Since at least some rise in temperature is likely irreversible, mitigating the effects of mosquito-borne diseases requires comprehensively addressing these trends, which requires adaptation – whether upgrading health infrastructures, changing social habits, ensuring equitable access or creating new solutions to reduce mosquito breeding – and new innovations in medicine.

There are currently limited prevention options for these mosquito-borne diseases, beyond vector-control measures. The remarkable progress made by medical and biopharma industries in recent decades, however, means that new preventive measures are within our reach, this includes Takeda’s progress in vaccine development. Scientific innovation offers welcome advancement in preventative measures to ultimately reduce the burden of disease and bring a protective solution to broader populations.

We know that the efforts of a single company aren’t enough to address the full scale of the problem and we know that major scientific breakthroughs – whether in the R&D phase or in the delivery of medicines and vaccines – come faster and are more frequently successful when companies work together.

The global response to COVID-19 is an excellent recent example of how collaboration can accelerate innovation and access to medicines and vaccines. International biopharma companies already cooperate on things such as R&D and clinical trials and governments should continue to use incentives to encourage such activity.

Public support is also critical and governments, universities and NGOs, as well as for-profit biopharma companies, must commit to making major and ongoing investments in developing new treatments and vaccines.

In addition to direct funding, governments can also support these efforts by favouring international collaboration, ensuring that a collective effort will prevail over short-term national interests. They can also leverage other mechanisms, such as the guaranteed purchase of doses or funding clinical trials, as well as educating vulnerable populations on risk factors and encouraging vaccination.

Governments can also help identify emerging health crises – particularly in the developing world – before they spread and invest in clinical care at local levels to strengthen public health systems.

With COVID-19 at least partially receding, largely due to the success of collective vaccine efforts, it might be tempting for governments to pare back on funding new biopharma research.

This would be a mistake. The curtailing of the COVID-19 pandemic illustrates the vital role vaccines play in our day-to-day health. It is a perfect example of why funding and rewarding biopharma research and innovation is so important. An ongoing financial commitment from governments and NGOs is critical to helping the biopharma industry contain new threats, particularly as the link between climate change and increased pandemics becomes more evident.

When we hear the word 'sustainable' most people likely think about reducing greenhouse gas emissions, which is incredibly important. Sustainability, however, is also about providing solutions to adapt to emerging and existing threats, so we can live longer and healthier lives. With the planet warming, the spread of mosquito-borne diseases into new regions appears inevitable, but I’m confident that the biopharma industry, given the right support, can play a leading role in helping humanity sustainably prepare for, prevent and ultimately overcome this urgent challenge.