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Mosquitoes that carry West Nile are becoming resistant to insecticides

John VanDenBerg suspects he was gardening when a mosquito got him.

It was September 2018, and VanDenBerg, then 67, had been feeling a little “off” for a few days, he said, like maybe he had the flu.

But one morning, as he was walking out of his Colorado home, he collapsed.

The Economics of Resistance

It would be extremely difficult to calculate, with any high degree of accuracy, the global economic impact of insecticide resistance. For starters, we must consider that insect management plays a pivotal role in a variety of sectors – agriculture, home and garden, forestry, structural applications, and vector control. Analysis of the totality of economic impacts arising from resistance in any one of these sectors quickly becomes a complicated interplay of variables that interact within that given system.

To account for the full economic impact, one must layer in the amount being spent on insect management and how much of that investment is lost to resistance, but also the economic impact of losses to the overarching objectives of a given program.

To calculate the impact, you must first calculate what is at risk.

How Does Insecticide Resistance Happen?

Check out this video by MalariaGen focusing on how natural selection drives insecticide resistance relating to malaria.

Dr. Cali Crampton: Protector of our Feathered Friends

Armed with a Ph.D. in Ecology, Evolution, and Conservation Biology from the University of Nevada at Reno, Dr. Lisa “Cali” Crampton is no stranger to the intricacies of avian ecosystems.

Her doctoral research explored the ecology and conservation of Silky-flycatchers (Phainopepla nitens), shedding light on the plight of these threatened passerines in southern Nevada. Not content with theoretical contributions, she led a dynamic team in designing an adaptive management plan as part of the regional Habitat Conservation Plan, a planning document that is recognized by the U.S. Fish and Wildlife Service as part of the enforcement of the Endangered Species Act, ensuring the preservation of threatened desert woodlands crucial to the survival of Phainopeplas and other sensitive species in Nevada.

Avian Malaria in the Sub-Antarctic

Avian malaria has recently been discovered in southern Chile and the introduction of beavers decades ago is partially responsible.

Birds on the Brink

Hardly anyone visits the desolate outpost of Coldfoot, one of Alaska’s few communities outside the Arctic Circle accessible by road. Its 34 residents live in rustic accommodations along the Dalton Highway. The town’s highlights include an inn, a café, a gas station and a basic airport with a gravel landing strip. All day long, 18-wheeler fuel trucks thunder by on supply runs between Fairbanks and the oil fields of Prudhoe Bay further north. Some will stop to eat and tank up at Coldfoot because the next human habitation is 234 miles away, a town grimly named Deadhorse.

They say Coldfoot got its name from the days of the 1900 Gold Rush when miners would come as far as this remote settlement before getting “cold feet” and turning back. It’s still a lonely place, but one unexpected visitor showed up recently inside an infected Swainson’s thrush (Catharus ustulatus): the avian malaria parasite, Plasmodium circumflexum.

In 2011, scientists tested 676 birds representing 32 resident and migratory bird species captured from three northern locations in Alaska: Anchorage (61°N), Fairbanks (64°N) and Coldfoot (67°N). In Anchorage and Fairbanks, they found 49 birds infected by Plasmodium parasites. In Anchorage, even resident birds and hatchlings of species such as the boreal chickadee (Poecile hudsonicus), the varied thrush (Zoothera naevia) and the fox sparrow  (Passerella iliaca) were found infected. The parasite was also detected in black-capped chickadees (Poecile atricapillus) and a myrtle warbler (Dendroica coronata coronata) in Fairbanks, indicating that transmission had occurred locally.

Vanishing Birds

If you were alive in the year 1970, more than one in four birds in the U.S. and Canada has disappeared within your lifetime.

According to research published online in September by the journal Science, wild bird populations in the continental U.S. and Canada have declined by almost 30% since 1970.

Dr. Salim Abdulla: The Heart and Soul of Malaria Research

Dr. Salim Abdulla is a distinguished clinical epidemiologist whose remarkable career has significantly impacted the global fight against malaria and emerging pathogens. With over 20 years of experience in conducting clinical trials and groundbreaking research, he has played a pivotal role in shaping national malaria policies and leading innovations in healthcare.

Throughout his career, Dr. Abdulla has focused on evaluating and introducing critical interventions in the fight against malaria. He conducted extensive research on insecticide-treated bednets (ITNs) and artemisinin-based combination therapies, leading to important advancements in national malaria policy formulation. Notably, he is currently engaged in the evaluation of new malaria vaccines and treatments, with the goal of achieving regulatory licensure.

Malaria by the Numbers

According to the 2022 World Malaria Report, despite disruptions to prevention, diagnostic and treatment services during the pandemic, countries around the world have largely held the line against further setbacks to malaria control.

Good news:
Progress towards malaria elimination is increasing; in 2021, there were 84 malaria endemic countries compared with 108 in 2000.

The Economics of Malaria

In the 2022 World Malaria Report, compiled by the World Health Organization (WHO), the total spend on funding the fight of malaria in 2021 was estimated at USD 3.5 billion. Over that year, the same report states that there were an estimated 247 million cases of malaria and 619,000 malaria deaths globally.

More recently, over the course of the 20th Century, malaria is believed to have claimed between 150–300 million lives. The disease is contracted predominantly in the tropical regions: sub-Saharan Africa, Asia and the Amazon basin. This is due to the prevalence of the Anopheles mosquito that transmits the disease. Poorer regions of Africa bear the vast majority of the burden. In 2021, around 95% of the diagnosed cases and deaths were on the African continent, 80% of which were children under the age of five. The disease is entirely preventable and curable with prompt diagnosis and effective methods of treatment which require sufficient investment and funding.