Outbreaks are more than a seasonal spike in cases

Dengue cases have been rising constantly, spurred on by urbanization and global travel.¹ On top of these factors, extreme weather events such as heavy rain or droughts can sometimes be associated with outbreaks.² While many dengue-endemic countries expect to see a spike in cases during the rainy season, outbreaks are a sudden unexpected increase in cases outside of this normal seasonal pattern.^3,4 Outbreaks are becoming more common and intense in some places.^3,4 For example, they happened once every 10 years in Jamaica prior to 2007 but now occur every 3-4 years.⁵

A state of emergency

For some specific countries that have declared a state of emergency in the past, the disruption of dengue outbreaks can be felt on a national level.^6,7 The case numbers caused by outbreaks can overwhelm healthcare systems.⁸ For instance, in February 2023, Peru declared a state of emergency for 90 days in some of its regions after a rise of 72% in dengue cases compared to the same period in 2022.^6,9 The burden of a dengue outbreak may be multi-faceted as detailed below.¹⁰

In those specific cases, dengue outbreaks can sometimes cause personal, medical, social, financial, and political challenges.¹⁰

Hospitals

In certain situations, in some countries, hospitals can sometimes become overstretched and may be unable to find beds for patients with some found in the corridors and sleeping on floors.¹¹ More rarely, demands on healthcare workers can lead to emotional exhaustion and burnout in some cases.¹²

Patients

In some cases long waiting times may result in patients visiting several clinics to find one able to treat them.¹⁰ Patients can also face significant costs for treatment that some can find difficult to pay.^13,14

Community

Fear and anxiety of contracting dengue can sometimes grow within the community.¹⁰ Some individuals anxious of a dengue infection, may add to the demand in over-capacity hospitals by asking for tests not required or recommended by doctors.¹⁰

Finances

The economic burden of dengue may be greater than some other infectious diseases, including cholera and viral stomach flu.¹⁵ One estimate put the total annual cost of dengue globally at US$8.9 billion.^16,17 Dengue can also impact a country’s tourism industry – for instance, Brazil was estimated to have lost over $100 million from a fall in tourism during its 2013 dengue outbreak.¹⁸

Politics

For some specific countries, the political demands in the midst of an outbreak can destabilize governments, who may face frustration and a lack of trust within the community over their perceived inefficient and slow dengue prevention and control efforts.^10,19 Dissatisfied communities may also be less likely to engage with government initiatives to fight dengue.¹⁰

Defeating dengue: outpacing the outbreaks

When outbreaks occur, there is no single solution to effectively manage them. Part of the solution though, is a fast response.^3,20 Surveillance systems to detect dengue cases and possible outbreaks early are helpful, along with effective management strategies which can be actioned quickly.³ Community education and engagement is a key part of any response.³ Vaccines too may have an important role in a multi-pronged strategy (including vector control) to reduce overall dengue burden.²¹ These measures combined, could help avoid outbreaks gathering pace in the future.

2023: a record-breaking year for dengue outbreaks

• Bangladesh recorded its worst ever outbreak²³

   

• Chad experienced its first ever outbreak²⁴

   

• The Americas reported 1.9 million cases in the first 5 months of 2023, which was more than that of 2021²⁵

   

• Argentina went through its deadliest dengue outbreak²⁵

   

• A record-breaking summer led to an outbreak in Jamaica⁵

   

• The government of Guatemala declared a national emergency due to a dengue outbreak²⁶

   

• Bolivia and Peru experienced record-breaking case numbers²⁵