The Jakarta administration is planning to release the eggs of lab-bred mosquitoes carrying the Wolbachia bacteria next week in Kembangan district, West Jakarta, in an effort to control dengue in the mayoralty.
The process involves health authorities distributing buckets filled with water and up to 150 Wolbachia-infected mosquito eggs.
“We are preparing more than 800 buckets for distributing to [selected] households in Kembangan,” Jakarta Health Agency head Ani Ruspitawati said on Wednesday, as quoted by kompas.com.
The buckets are placed in a suitable environment for the eggs to hatch and develop into adult mosquitoes that then go on to infect other mosquitoes with Wolbachia, helping to curb the spread of dengue.
Dengue fever is a viral disease transmitted through the bite of Aedes aegypti and Aedes albopictus mosquitoes, invasive species common in urban environments and tropical climates that have spread across the globe.
The dengue virus is weakened when it interacts with Wolbachia, a bacterium found in 60% of insect species but not in Aedes aegypti.
The microorganism was first identified in the early 20th century by American scientists Marshall Hertig and Simeon Burt Wolbach.
Wolbachia competes with the dengue virus inside infected mosquitoes and makes it harder for the virus to reproduce, thus reducing the mosquitoes’ ability to transmit the disease to humans.
When male mosquitoes infected with Wolbachia mate with non-infected females, the eggs produced do not hatch.
If either the female or both the male and female carry Wolbachia, the eggs also carry the bacterium, resulting in adult mosquitoes that are inhibited from spreading the dengue virus.
The so-called Wolbachia method is a new tool in the country’s arsenal for combating dengue, in addition to the decades-old Menguras, Mengubur dan Menutup (drain, bury and cover) campaign, also known as 3M, to eliminate water sources as potential mosquito breeding grounds.
The results of a trial in Yogyakarta by researchers from Gadjah Mada University (UGM) and the World Mosquito Program of Australia’s Monash University, published in mid-2020, showed a 77% reduction in the incidence of “virologically confirmed dengue” in Wolbachia-treated areas compared to untreated areas.
“We hope that by 2025, we will have released Wolbachia-infected mosquito eggs in all districts in West Jakarta,” said Ani from the city health agency, which aims to infect 60% of the mayoralty’s Aedes aegypti population with the bacterium by 2025.
Ani also urged more residents to participate in the project, noting that Jakarta had recorded more than 12,000 dengue fever cases as of September.
According to Anas Ma’ruf, the Health Ministry’s acting communicable diseases director, West Jakarta was chosen as the site for releasing the Wolbachia-infected eggs because of the high number of local dengue cases.
Health agency data released in March showed that among the city’s five mayoralties, West Jakarta had the highest number of dengue fever cases with 716, followed by South Jakarta with 576 and East Jakarta with 562.
West Jakarta’s caseload had dropped to 46 cases by mid-August, Antara reported.
In 2021, Kembangan recorded the highest dengue caseload among all districts in West Jakarta.
Outside Jakarta, the Health Ministry has piloted the Wolbachia project in Semarang in Central Java, Bandung in West Java, Bontang in East Kalimantan and Kupang in East Nusa Tenggara.
Riris Andono Ahmad of the UGM Center for Tropical Medicine said that following the recommendation of the World Health Organisation in 2021 to use Wolbachia to control dengue outbreaks, other countries to use the method included Australia, Brazil, Fiji and Mexico. — The Jakarta Post/ANN
