Banner by Amy Zhang

Sucking the Life from Africa 

by Janin Apreku

Despite my fatigue from my lengthy trip from Accra to Northern Ghana, I stepped inside my grandmother’s house and the hairs on the inside of my nose instantly perked up. The smell was so peculiar. A seven-year-old me peered up at my father. Tugging on his arm, I asked, “What’s that smell?” My father informed me it was to take care of the bugs. As exhaustion took over me, I thought nothing of it and went to sleep in a room filled with netted windows to prevent entry of insects. While I was not so concerned with the possibility of diseases—I’m glad my family was.  

Mosquito-borne diseases (MBDs) are extremely devastating, especially to Africa. Africa is the only continent on Earth that spreads across the northern and southern hemispheres, allowing for high biodiversity. This increased biodiversity creates greater exposure to MBDs in domesticated animals, and therefore, higher animal-to-human transmissions. The population growth in Africa, combined with environmental factors, alters the natural ecosystems, creating a recipe for disaster.  

While there are many types of MBDs, the most prevalent are Dengue, Malaria, and West Nile Virus. Dengue is spread in tropical and subtropical regions by mosquitoes endemic to both urban and rural areas. Humans serve as an amplification factor in the transmission of the virus across populations. Mosquitoes bite the infected, and they are then able to transmit the virus to a different healthy individual. After infection, the virus incubates for two weeks before presenting symptoms including fever, nausea, and joint pain. Diagnosing the specific condition is difficult as the symptoms are similar across different MBDs. Dengue does not have an exact treatment, so management of the disease is focused on controlling symptoms.  

Malaria is characterized by an infective parasite transmitted through a mosquito’s saliva. These small pieces of the parasite travel to the liver to mature, then enter the bloodstream. Malaria is treated by a family of drugs derived from the aromatic organic compound quinoline. The primary feature of this drug is to kill the parasite and prevent its symptom-causing proteins from being produced.  

West Nile Virus follows a transmission cascade; the virus is transmitted from birds to mosquitoes to humans. While still reflecting the regular symptoms found in MBDs, West Nile has the potential to cause meningitis, encephalitis, and paralysis. Symptoms of infection begin to show up two to fourteen days after exposure, and can greatly vary in severity. 

One major way to decrease the transmission of these MBDs is through proper public health education. The mnemonic DELIVER was established as an easy way for the public to remember how to protect themselves against the effects of these MBDs. It outlines methodologies promoting individual protection and protective infrastructure. “D” concerns safety around doors—screen installation, self-closing, and fit tightly to prevent mosquito entry. “E” denotes eaves, the spaces between walls and roofs, which should also be closed or screened. “L” reminds people that lifting houses off the ground reduces mosquito access.  “I” stands for insecticide-treated nets (ITNs), which are recommended for sleeping. “V” is a call for proper ventilation to keep houses cool and comfortable, as well as bed nets in addition to screened doors. “E” is for environmental management in order to eliminate mosquito breeding sites through drainage, waste disposal, and water storage practices. Finally, “R” states that roofs that are well constructed, ensuring no cracks.   

The DELIVER strategy emphasizes that effective mosquito control requires a multi-pronged approach. By combining physical barriers, personal protection, and environmental management, it aims to create healthier homes and communities. The success of DELIVER relies not only on the implementation of these interventions, but also on strong political leadership, private sector engagement, active community participation, and comprehensive education initiatives. 

As the world gains awareness about the increasing danger of the spread of MBDs, many studies are being performed to discover new ways to combat them. Specific gene editing is one mode of research aiming to combat the spread of Malaria. This research targets gene editing in Anopheles stephensi using the ReMOT control method. Researcher Vanessa Macias and others from the Liverpool School of Tropical Medicine specifically target a gene vital for female fertility, in order to disrupt it and decrease overall mosquito population growth. The ReMOT technique injects CRISPR-Cas9 into the ovaries. This results in successful gene editing within the targeted gene in the parental generation. The edited gene is then inherited by offspring. The success of this targeted, heritable gene disruption using ReMOT opens the door for further research into similar strategies targeting other genes essential for mosquito survival, reproduction, and disease transmission. 

In addition to gene editing, the toxic male technique is another method to combat the spread. Since only female mosquitoes bite and transmit diseases, targeting males with insecticides can disrupt the mosquito population's reproductive cycle without directly impacting human health. One approach involves releasing male mosquitoes contaminated with insecticides, which they then transfer to females during mating, killing the females and their offspring. Another strategy focuses on genetically engineering males to produce insecticidal proteins, which are passed to females during mating and significantly shorten their lifespan. Both methods aim to reduce mosquito populations in a targeted and environmentally safe way, which is better than traditional insecticide spraying. 

Combating MBDs requires collaboration around the world. The development of new protective procedures and technology can lead a new generation of people to not be weary of the dangers of MBDs. Although difficult, the current steps which are being taken to combat MBDs show that Africa’s future does not have to be marked by more mosquito-related deaths. As more research is produced I become ever hopeful that these preventive measures will release the African continent from the reign of MBDs. As I return to Ghana in the future I hope that the past is different from the present. I believe that through these preventive practices I will soon be able to forget that nostalgic smell and tell my father of the new future.