Dengue cases drop to 20-year low following large-scale releases of Wolbachia mosquitoes in the Aburrá Valley, Colombia

livus, 5 months ago

From the article:

The findings arrive in a critical year which has seen the Americas already top 3.5 million cases of dengue — the second-highest annual incidence of the disease since 1980. Across the globe, there have been more than 4.5 million cases and over 4,000 dengue-related deaths reported from 80 countries/territories globally.

The largest contiguous implementation of Wolbachia mosquito releases to-date confirms WMP’s Wolbachia method is feasible and effective at a large scale...

WMP’s groundbreaking Wolbachia solution for protecting communities from mosquito-borne diseases, is a one-time, safe and cost-effective method, which has been deployed in 14 countries over the past decade. A natural bacteria found in half of all insect species, Wolbachia blocks the transmission of viruses when introduced into Aedes aegypti mosquitoes.

The effectiveness of Wolbachia for controlling dengue has been demonstrated in multiple field trials. More than 11 million people in Asia-Pacific and Latin America are already benefiting from this protection in communities where Wolbachia has been released.

Short-term releases of Wolbachia mosquitoes in dengue-affected communities allow Wolbachia to spread into the local mosquito population, effectively shielding it against dengue and other viruses. Once established, Wolbachia remains in the local mosquitoes for years without additional releases...

Effective at scale

Over the seven years of releases in the Aburrá Valley, a total of just over 88 million Wolbachia mosquitoes were released, with Wolbachia established throughout the target mosquito populations.

Alongside monitoring of dengue cases reported to public health authorities, WMP conducted a case-control study in primary care clinics in northeast Medellín between 2019 and 2021. This found that dengue incidence was reduced by half among participants resident in Wolbachia-treated neighbourhoods compared to neighbourhoods where Wolbachia had not yet been released.

These results support WMP’s previous findings, most notably in Yogyakarta, Indonesia. WMP’s gold-standard randomised trial in the Indonesian city showed a 77% reduction in dengue incidence and an 86% reduction in dengue hospitalisations in Wolbachia treated areas compared with untreated areas. Efficacy was equivalent for all four dengue virus serotypes...

“What makes Wolbachia different from — and more cost-effective than — conventional vector control is that after an initial investment to implement, there is sustained community-wide protection against mosquito-borne diseases without any ongoing investment of resources or behaviour change required. Because the health and economic benefits accumulate over time, Wolbachia is a long-term solution that can pay for itself.”