3Qs: Why a mosquito is more than just a summertime pest
July 26, 2012 in Diseases, Conditions, Syndromes
You know that mosquito bite youre scratching like crazy on that hot, summer night? According to Rebeca Rosengaus, associate professor of biology in the College of Science, it may be a vector, or carrier, for diseases. And while we may think that spraying pesticides to prevent the spread of some of these diseases, such as West Nile Virus, may be a good solution, Rosengaus says its not sustainable. Northeastern University news office asked the expert to explain why a mosquito is more than just a summertime pest.
How do insects, such as mosquitoes, become vectors for disease or parasites and then transmit them to us?
Insects comprise about 83 percent of the known animal life, and 50 percent of all living organisms. Today at least 1 million insect species have been identified. While many insects are beneficial to humans, some of them are also detrimental, particularly those that become agricultural pests and carriers of diseases.
The microorganisms that cause diseases such as Eastern equine encephalitis, West Nile virus or malaria usually have complex life cycles. The microbes require multiple hosts in order to complete their maturation. Insects happen to be excellent carriers of these pathogens because they are transported from one host and injected into the subsequent host. In a way, microbes are hitchhiking inside the unaware insect.
The female mosquito requires a blood meal prior to reproduction. She becomes infected during the blood meal, disperses the microbe while flying and then re-infects a new host once she bites again.
The interactions among the microbial pathogens, the multiple hosts, and the insect vectors have been around for millions of years and do not necessarily only affect humans. In general, mosquitoes could bite any terrestrial warm-blooded animal at some stage of its life.
Some have called for increasing the use of pesticide spraying after pools began testing positive for the West Nile virus. Is pesticide spraying a sustainable solution to problem? Which other vector-control options are researchers currently investigating?
Theoretically speaking, you should be able to reduce infection rates by controlling the population size of the insect carriers. This, however, is easier said than done.
Insects can be killed with toxic chemical compounds (pesticides) and biological control agents (fungal or bacterial insect pathogens), and by irradiation and subsequent release of infertile males.
Researchers have recently attempted to genetically engineer the mosquito itself or its gut bacteria so that the mosquito becomes refractive to Plasmodium, the malaria-causing microorganism. The later strategy of manipulating the bacteria in the gut of the mosquito seems to be effective. When mosquitoes were fed a blood meal containing the genetically engineered bacteria, the prevalence of Plasmodium in the gut of the insect was reduced by 85 to 90 percent. These different techniques vary in their effectiveness, and it is important to keep in mind that both short and long-term cost/benefit analyses of these strategies need to be taken into consideration if we are to control insect vector populations successfully.
In the short term, pesticides would be efficient in reducing mosquito density. However, mosquito populations can evolve resistance against pesticides, rendering them nonsusceptible to the pesticide in the long run. An identical scenario has been responsible for the evolution of antibiotic resistance in bacteria. Thus, we should learn from previous experience and avoid fostering the evolution of pesticide-resistant mosquitoes by restricting the widespread use of pesticides.
Scientists have connected global warming to expanded migratory patterns for insects. How will global warming impact the range of incidence of mosquito-borne diseases?
There is no doubt the Earth is warming. This phenomenon has been accompanied by an expansion northward of animals that otherwise would have been restricted by the cold winter months to lower latitudes.
Insects are no exception. The probability also exists that infected mosquitoes can now not only reach new locations, but also thrive in warmer environments for longer periods of time. This will translate into higher risks of infection for humans and other animals as the mosquitoes search for new blood meals.
Provided by
Northeastern University
-
Tracking America's physical activity, via smartphone
Jun 19, 2012 |
not rated yet |
0
-
The risk of carrying a cup of coffee
Jun 15, 2012 |
not rated yet |
0
-
Why 'trickle-up' innovation may shape the global economy
Jul 19, 2012 |
not rated yet |
0
-
Chipping away at cancer
Jun 25, 2012 |
not rated yet |
0
-
3Qs: Celebrating America's independence
Jul 04, 2012 |
not rated yet |
0
-
Motion perception revisited: High Phi effect challenges established motion perception assumptions
Apr 23, 2013 |
3 / 5 (2) |
2
-
Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update)
Apr 02, 2013 |
4.5 / 5 (11) |
5
-
The visual system as economist: Neural resource allocation in visual adaptation
Mar 30, 2013 |
5 / 5 (2) |
9
-
Separate lives: Neuronal and organismal lifespans decoupled
Mar 27, 2013 |
4.9 / 5 (8) |
0
-
Sizing things up: The evolutionary neurobiology of scale invariance
Feb 28, 2013 |
4.8 / 5 (10) |
14
-
Classical and Quantum Mechanics via Lie algebras
Apr 15, 2011
- More from Physics Forums - Independent Research
More news stories
Estimates reveal low population immunity to new bird flu virus H7N9 in humans
The level of immunity to the recently circulating H7N9 influenza virus in an urban and rural population in Vietnam is very low, according to the first population level study to examine human immunity to the virus, which was ...
Diseases, Conditions, Syndromes
1 hour ago |
not rated yet |
0
|
Study shows COPD is associated with significant and persistent pain
Chronic obstructive pulmonary disease (COPD) is primarily associated with the respiratory symptoms that are its hallmark, but in fact, patients who struggle with the disease also experience significant amounts of chronic ...
Diseases, Conditions, Syndromes
1 hour ago |
not rated yet |
0
Inflammation is associated with depression in COPD patients
Depression is common in patients with chronic obstructive pulmonary disease (COPD) and has been linked with disease severity and impaired quality of life. Now, for the first time, researchers at the University of Pittsburgh ...
Diseases, Conditions, Syndromes
1 hour ago |
not rated yet |
0
Study finds vitamin C can kill drug-resistant TB (w/ video)
In a striking, unexpected discovery, researchers at Albert Einstein College of Medicine of Yeshiva University have determined that vitamin C kills drug-resistant tuberculosis (TB) bacteria in laboratory culture. The finding ...
Diseases, Conditions, Syndromes
1 hour ago |
5 / 5 (1) |
0
|
Exercise levels may predict hospitalizations in COPD population
Clinical measurement of physical activity appears to be an independent predictor of whether or not patients with chronic obstructive pulmonary disease (COPD) will end up being hospitalized, according to a new study conducted ...
Diseases, Conditions, Syndromes
3 hours ago |
not rated yet |
0
B vitamins could delay dementia
(Medical Xpress)—Despite spending billions of dollars on research and development, drug companies have been unable to come up with effective treatments for dementia and Alzheimer's Disease (AD). Now, A. ...
Waiting for a sign? Researchers find potential brain 'switch' for new behavior
You're standing near an airport luggage carousel and your bag emerges on the conveyor belt, prompting you to spring into action. How does your brain make the shift from passively waiting to taking action when ...
Common food supplement fights degenerative brain disorders
Widely available in pharmacies and health stores, phosphatidylserine is a natural food supplement produced from beef, oysters, and soy. Proven to improve cognition and slow memory loss, it's a popular treatment for older ...
Aggressive behavior linked specifically to secondhand smoke exposure in childhood
Children who are exposed to secondhand smoke in early childhood are more likely to grow up to physically aggressive and antisocial, regardless of whether they were exposed during pregnancy or their parents have a history ...
If you can remember it, you can remember it wrong
(Medical Xpress)—Native peoples in regions where cameras are uncommon sometimes react with caution when their picture is taken. The fear that something must have been stolen from them to create the photo ...
Insight into the dazzling impact of insulin in cells
Australian scientists have charted the path of insulin action in cells in precise detail like never before. This provides a comprehensive blueprint for understanding what goes wrong in diabetes.