Page 28 - aruba-today-20191123

A28 SCIENCE
Saturday 23 November 2019
Bacteria-infected mosquitoes take bite out of deadly dengue

By LAURAN NEERGAARD mosquitoes for eight years
AP Medical Writer and counting, whether
WASHINGTON (AP) — They mosquitoes maintain den-
still bite, but new research gue resistance that long in
shows lab-grown mosqui- harder-hit regions remains
toes are fighting danger- to be seen.
ous dengue fever that they "The results are pretty excit-
normally would spread. ing — strong levels of re-
Dengue infections appear ductions — but there clear-
to be dropping fast in com- ly are going to be things to
munities in Indonesia, Viet- be learned from the areas
nam, Brazil and Australia where the reductions are
that are buzzing with the not as great," McGraw
specially bred mosquitoes, said.
an international research More than half of insect
team reported Thursday. species, from fruit flies to
It's the first evidence from butterflies, naturally are in-
large-scale field trials that fected with Wolbachia —
mosquitoes are less likely to but not the main dengue-
spread dengue and similar spreader, Aedes aegypti
viruses when they also car- mosquitoes. They're day-
ry a type of bacteria that's time biters that thrive in hot
common in insects and urban and suburban locali-
harmless to people. ties where, for now, wide-
Rather than using pesti- In this Wednesday, Sept. 24, 2014, file photo, a technician releases mosquitoes that are infected spread pesticide spraying
cides to wipe out bugs, with a dengue-blocking bacteria called "Wolbachia" in the Tubiacanga neighborhood of Rio de is the main protection.
"this is really about trans- Janeiro, Brazil. Researchers with the World
forming the mosquito," said Associated Press Mosquito Program first in-
Cameron Simmons of the dengue recorded by local State University professor project. jected mosquito eggs with
nonprofit World Mosquito authorities in an Indonesian Zhiyong Xi, who wasn't in- More research is need- Wolbachia in a lab. Infect-
Program that is conducting community near the city volved with the project but ed, specialists cautioned. ed females then pass the
the research. of Yogyakarta since the has long studied how Wol- These studies used local bacteria on through their
The first hint of success 2016 release of Wolbachia- bachia can turn mosqui- health groups' counts of eggs. Releasing enough
came from Australia. Mos- carrying mosquitoes. That's toes against themselves. dengue cases rather than Wolbachia carriers, both
quitoes bred to carry Wol- compared to dengue Reducing disease "is the ul- blood tests, noted Penn the females that bite and
bachia bacteria were transmission in a nearby timate success of our field," State University professor the males that don't, allows
released in parts of North area where regular mos- added University of Mary- Elizabeth McGraw. And mating to spread the bac-
Queensland starting in quitoes do the biting. land biologist Brian Lovett, while Wolbachia has per- teria through a local mos-
2011, and gradually spread Researchers found a similar who also wasn't part of the sisted in North Queensland quito population.q
through the local mosqui- drop in a community near
city of Nha Trang. And Spain has permits to build giant
to population. Dengue is the southern Vietnamese
transmitted when a mos-
quito bites someone who preliminary results suggest
is infected, and then bites large declines in dengue telescope blocked in Hawaii
another person, but some- and a related virus, chikun-
how Wolbachia blocks that gunya, in a few neighbor- By JOSEPH WILSON
— and local transmission hoods in Brazil near Rio de Associated Press
has nearly disappeared in Janeiro. BARCELONA, Spain (AP)
those North Queensland The studies are continuing — The director of a Span-
communities, Simmons said in those countries and oth- ish research center said
in an interview. ers. But the findings, pre- Wednesday that a giant
The real test would come sented at a meeting of the telescope, costing $1.4 bil-
in dengue-plagued areas American Society for Tropi- lion, is one step nearer to
in Asia and Latin America cal Medicine and Hygiene, being built on the Canary
that regularly experience suggest it's possible to turn Islands in the event an in-
outbreaks where millions at least some mosquitoes ternational consortium
get the painful and some- from a public health threat gives up its plans to build it
times deadly disease. into nuisance biters. in Hawaii.
Thursday, Simmons' team The work marks "exciting Canary Islands Astrophys-
reported a 76% decline in progress," said Michigan ics Institute Director Rafael This July 24, 2009 file photo shows the Gran Telescopio Canarias,
one of the the world's largest telescopes, at the Observatorio
Rebolo told The Associated del Roque de los Muchachos on the Canary Island of La Palma,
Press that a building permit Spain.
for the telescope has been Associated Press
granted by the town of ians consider the Mauna Observatory, was chosen
Puntagorda on the island Kea summit sacred and as a back-up site for the
of La Palma. their protests have stopped telescope in 2016.
The international consor- construction from going As point man for the al-
tium backing the construc- ahead since mid-July. The ternative site, Rebolo said
tion of the Thirty Meter Tele- Spanish island of La Palma, he maintains regular con-
scope (TMT) wants to build which already hosts several tacts with the consortium
it atop Hawaii's tallest peak. powerful telescopes at the and Spain's ministry for
But some native Hawai- Roque de los Muchachos science.q