REFILE-US STOCKS-S&P, Nasdaq close at new highs as Wall Street rides bull momentum

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By Stephen Culp
NEW YORK, Aug 24 (Reuters) - The S&P 500 and the Nasdaq
reached new record closing highs on Monday as optimism over
potential medical advances in the war against the coronavirus
pandemic pushed all three major U.S. stock indexes higher.
The benchmark S&P 500 reclaimed its February closing high
last week, confirming a bull market and the fastest recovery
from a bear market trough on record. Of note, the Dow Transports index .DJT , often considered a
barometer of U.S. economic health, handily outperformed the
broader market.
"There's been a broadening in this rally and that's what's
reflected in the transports," said Chuck Carlson, chief
executive officer at Horizon Investment Services in Hammond,
Indiana. "(Higher) volume is accompanying this expanding
breadth, and those are all bullish things."
Markets worldwide were given a boost by new developments in
the global race to battle the coronavirus, including an
announcement from the Food and Drug Administration that it had
given emergency authorization for the use of plasma from
recovered patients as a treatment option.
However, the World Health Organization expressed skepticism
about the treatment due to "low quality" data. The Trump administration is considering fast-tracking an
experimental COVID-19 vaccine being developed by AstraZeneca Plc
AZN.L and Oxford University in hopes it could be deployed in
the United States before Americans head to the polls in
November. "There's an element of that news helping the 'reopening
trade,' which is a euphemism of economically sensitive stocks
performing better," Carlson added.
The four-day Republican national convention gets under way
on Monday, with the party nominating President Donald Trump for
a second term and making the case for his re-election.
On Capitol Hill, partisan wrangling over stalled coronavirus
aid talks continued, and congressional Democrats and Republicans
remain at loggerheads over funding levels and unemployment
benefits. Market participants will pay close attention to U.S. Federal
Reserve Chairman Jerome Powell's remarks on monetary policy at
this week's Kansas City Fed Jackson Hole symposium, which is
being held this year in a virtual format.
Unofficially, the Dow Jones Industrial Average .DJI rose
384.61 points, or 1.38%, to 28,314.94, the S&P 500 .SPX gained
34.93 points, or 1.03%, to 3,432.09 and the Nasdaq Composite
.IXIC added 69.77 points, or 0.62%, to 11,381.57.
Of the 11 major sectors in the S&P 500, all but healthcare
.SPXHC ended the session in the black.
Energy .SPNY and financials .SPSY enjoyed the largest
percentage gains.
Ahead of its 4-to-1 share split on Friday, Apple Inc
AAPL.O closed above $500 days after becoming the first public
U.S. company to top $2 trillion in market value.