Malaria

[GordMay]

Researchers discover new weapon against antibiotic resistance.
It also fights malaria!

A team, from Florida International University’s [FIU] Herbert Wertheim College of Medicine, developed arsinothricin [AST], to combat the rise of antibiotic-resistant bacteria. Lab tests proved AST effectively defeated the most notorious, including E. coli and Mycobacteria, which cause tuberculosis.

Collaborating with malaria researchers, in the College of Arts, Sciences & Education, they've recently also found AST prevents Plasmodium falciparum, the parasite that causes malaria, from infecting mosquitoes*. The discovery, recently published in ‘Microorganisms’ [1], paves the way for AST to be developed into a more effective antimalarial drug, for humans.

* Malaria spreads, when a mosquito bites someone with malaria, and the parasites in the blood infect the mosquitoes. Ten days later, infected mosquitoes can bite another person, and transmit the disease to them. Current antimalarials don't completely stop transmission, meaning patients can continue to infect mosquitoes, before they recover. When FIU researchers tested AST on liver, kidney and intestinal cells, AST targeted the malaria parasite, lurking in human cells, but didn't damage the cells themselves.
Using AST, to prevent parasites from spreading to mosquitoes, breaks the malaria life cycle.

[1] “ Arsinothricin Inhibits Plasmodium falciparum Proliferation in Blood and Blocks Parasite Transmission to Mosquitoes” ~ by Masafumi Yoshinaga et al
Open Access ➥ https://www.mdpi.com/2076-2607/11/5/1195

[GordMay]

Mosquitoes Carry Nasty Diseases. Here’s How to Protect Yourself
Malaria grabs headlines, but U.S. residents are more likely to encounter West Nile virus and other mosquito-borne illnesses.
More ➥ https://www.scientificamerican.com/a...tect-yourself/

The CDC tracks nine Mosquito-Borne Diseases [and 13 Tickborne Diseases], in a surveillance system [ArboNET], dedicated to monitoring so-called arboviruses — viruses transmitted by arthropods — that are spread by mosquitoes and ticks. (Malaria, a parasitic infection, isn’t included in the database.)
ArboNET ➥ https://www.cdc.gov/mosquitoes/mosqu...s/ArboNET.html

[GordMay]

Which mosquito repellents work best?

Scientists, at the New Mexico State University Molecular Vector Physiology Laboratory*, have studied [1] different types of mosquito repellents, and their efficacy, for over a decade.
Here's what they found [1]:

Mosquito repellents that don't work:

Bracelets don't work. Department stores and pharmacy chains sell hundreds of different varieties of bracelets. They are marketed as "mosquito repellent" bands, wristbands and watches, and their materials can vary from plastic to leather. Even if they are loaded with repellents, they can't protect your whole body from mosquito bites.

Ultrasonic repellent devices don't work. These come as electrical plug-ins, free-standing varieties or watchlike accessories that claim to emit a high-frequency sound that deters mosquitoes by mimicking bats. However, in scientific studies, ultrasonic repellent devices fail to repel mosquitoes. In fact, when our lab tested one of these devices, we found a slight increase in mosquito attraction to the wearer.

Dietary supplements [vitamin B, garlic etc] don't work. No scientific evidence shows these supplements protect people from mosquito bites.

Light-based repellents don't work. These devices come as colored light bulbs, and they don't attract insects that fly toward white light. This approach works well on moths, beetles and stinkbugs, but not on mosquitoes.

Mosquito repellents that do work:

Here is our ranking of what does work, starting with the best repellent/active ingredient.

DEET works. DEET, chemical name, N,N-diethyl-meta-toluamide, was developed in the 1950s by the U.S. Army and is a well-established mosquito repellent with a long history of use. The higher the percentage, the longer the protection time is – up to six hours.

Picaridin works. This synthetic repellent can protect for up to six hours at a 20% concentration. This repellent is a promising alternative for DEET.

Oil of lemon eucalyptus, or OLE, works. OLE, with the active ingredient PMD, is a plant-based alternative to DEET and picaridin. Its repellent properties can last for up to six hours.

Other essential oils – some work, some not so much. We applied 20 different essential oils in a 10% essential oil lotion mixture to volunteers' skin.

Clove oil works. This oil, with the active ingredient eugenol, can protect from mosquito bites for over 90 minutes at a 10% concentration in lotion. Cinnamon oil works. This oil, with the active ingredients cinnamaldehyde and eugenol, can protect from mosquitoes for over 60 minutes at a 10% concentration in lotion. Geraniol and 2-PEP, or 2-phenylethyl propionate, work for about 60 minutes at a 10% concentration in lotion. Citronella oil works, just not so great. We found citronella oil at a 10% concentration only protected from mosquito bites for about 30 minutes.

Based on our study [1], we recommend using repellents with the active ingredient DEET if you live in or are traveling to regions with a high risk of vector-borne disease transmission. However, plant-based repellents will work just fine to prevent nuisance mosquito bites in low-risk areas, as long as you reapply them as needed.



[1] “Repellent efficacy of 20 essential oils on Aedes aegypti mosquitoes and Ixodes scapularis ticks in contact-repellency assays” ~ by Hailey A. Luker et al
➥ https://www.nature.com/articles/s41598-023-28820-9
or
➥ https://pubmed.ncbi.nlm.nih.gov/36717735/



* Molecular Vectory Physiology Lab at New Mexico State University
➥ https://www.hansenmvplab.com/?ftag=MSF0951a18

➥ https://artsci.nmsu.edu/news-events/...repellent.html



See also [Videos]:

NMSU researcher testing the efficacy of essential oils in repelling mosquitos ➥ https://youtu.be/L184ptwu074

Why Mosquitoes Bite Some People More Than Others ➥ https://youtu.be/38gVZgE39K8