FILE - In this Feb. 26, 2015 photo taken through the eyepiece of a microscope, human cells infected with the flu virus glow green under light from a fluorescence microscope at a laboratory in Seattle. The U.S. government estimates that 80,000 Americans died of flu and flu complications in the winter of 2017-2018 - the highest flu-related death toll in at least four decades. (AP Photo/Ted S. Warren)

FILE - In this Sept. 6, 2018, file photo, House Minority Leader Nancy Pelosi, D-Calif., speaks during her weekly news conference on Capitol Hill in Washington. Consumer and health care groups say they’re trying to block a move by the pharmaceutical industry to commandeer must-pass opioids epidemic legislation as a vehicle for rolling back drugmaker discounts to Medicare beneficiaries with high prescription costs. Republican leaders were saying little about behind-the-scenes discussions on Sept. 21,, but a spokesman for Pelosi calls it a “a multi-billion dollar handout to Big Pharma.” (AP Photo/Jose Luis Magana, File)

Zimbabwe Health Minister Obadiah Moyo washes his hands before entering a cholera quarantine area in Harare, Friday, Sept. 14, 2018, after a cholera emergency was declared in Zimbabwe's capital following the deaths of more than 20 people. The deaths in Harare have many fearing a repeat of the outbreak that killed thousands in 2008.(AP Photo/Tsvangirayi Mukwazhi)

FILE - This Dec. 4, 2013 file photo shows vials of flavored liquid at a store selling electronic cigarettes and related items in Los Angeles. On Wednesday, Sept. 12, 2018, U.S. health officials said teenage use of e-cigarette has reached “epidemic” levels in the U.S. and are calling on the industry to address the problem or risk having their flavored products pulled off the market. (AP Photo/Reed Saxon, File)

FILE - In this May 10, 2012, file photo, a doctor holds Truvada pills at her office in San Francisco. New research shows more promise for using AIDS treatment drugs, such as Truvada, as a prevention tool, to help keep uninfected people from catching HIV during sex with a partner who has the virus. Truvada has been shown to help prevent infection when one partner has the virus and one does not, but the evidence so far has been strongest for male-female couples. (AP Photo/Jeff Chiu, File)

FILE - In this Feb. 12, 2018, file photo, LGBT activists shout slogans during a rally against a planned revision to Indonesia's criminal code that would criminalize unmarried and gay sex outside the Parliament in Jakarta, Indonesia. The death of a 20-year-old man with HIV who died after "effectively committed suicide" by stopping anti-viral medication is a sign of an out of control but little acknowledged epidemic of HIV among gay men in Indonesia that researchers say is now being fueled by a gay hate climate fostered by the country's conservative political and religious leaders. (AP Photo/Tatan Syuflana, File)