Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
Coronavirus Antibody Tests Still Not Accurate Enough: CDC
Coronavirus antibody test results may not be accurate enough to help guide decisions about whether to allow large groups of people to gather at work, schools, dormitories, correctional facilities and other locations, the U.S. Centers for Disease Control and Prevention said Wednesday.
The agency also said too little is known about what the presence of antibodies means in terms of a person's future immunity, CBS News reported.
Antibody tests, also called serologic tests, are meant to determine if a person has antibodies to the new coronavirus after being infected.
Widespread, accurate antibody testing could help track the spread of the new coronavirus and the actual death rate from COVID-19, but the CDC said research on antibodies produced in response to the new coronavirus is still ongoing and people who test positive for the antibodies shouldn't assume they have immunity against the coronavirus, CBS News reported.
Everyone -- including those who've tested positive for antibodies or have had the coronavirus -- should continue to follow preventative measures such as social distancing, proper hygiene and the use of personal protective equipment, the CDC advised.
Large U.S. Pharmacy Chains Played Role in Opioid Crisis, Lawsuit Claims
Large pharmacy chains including CVS, Rite Aid, Walgreens, Giant Eagle and those operated by Walmart played a role in the United States' opioid epidemic, alleges a lawsuit filed in federal court in Cleveland by two Ohio counties.
It charges that the chains sold millions of pills in small communities, gave bonuses to pharmacists who sold large amounts of prescription opioids, and partnered with drug makers to promote the drugs as safe and effective, The New York Times reported.
Only CVS responded to a request for comment.
"Opioids are made and marketed by drug manufacturers, not pharmacists. Pharmacists dispense opioid prescriptions written by a licensed physician for a legitimate medical need," CVS said in a statement to the Times.
The other companies have issued similar statements in the past, according to the newspaper.
Drug makers and distributors have been the main focus of the thousands of lawsuits launched in relation to the U.S. opioid crisis, but few legal cases against large pharmacy chains have advanced, The Times reported.
AIDS Activist and Playwright Larry Kramer Dies at 84
U.S. AIDS activist and writer Larry Kramer died Wednesday in Manhattan at age 84.
The cause of death was pneumonia, according to his husband, David Webster, The New York Times reported.
Kramer struggled with illness for much of his adult life, including infection with the AIDS-causing HIV virus. He also had a liver disease and required a liver transplant.
Kramer helped found the Gay Men's Health Crisis, the first service organization for people with HIV, in 1981, and his aggressive demands for a strong response to the AIDS crisis helped change U.S. health policy in the 1980s and 90s, according to The Times.
He was also a prolific writer, and is probably best known for a largely autobiographical play chronicling the AIDS movement, "The Normal Heart," first produced in 1985.
Kramer had a cantankerous, rabble-rousing approach to activism. One target in 1988 was Dr. Anthony Fauci, longtime director of the National Institute of Allergy and Infectious Diseases. Kramer called him a killer and "an incompetent idiot," for what Kramer saw as the agency's neglect of AIDS issues.
But that relationship grew less rancorous with time, and in years to come Fauci and Kramer became friends and colleagues in the fight against HIV/AIDS.
"Once you got past the rhetoric," Fauci told the Times, "you found that Larry Kramer made a lot of sense, and that he had a heart of gold."
Preventative Meds Help Reduce Rebound Headaches: Study
Withdrawal therapy combined with early preventative medications help ward off medication overuse headaches (also called rebound headaches), a new study says.
These headaches typically occur in people who suffer from migraines, cluster headaches or tension-type headaches and take pain medications that don't work. When they don't get relief from their pain, they take another pill, which can lead to a rebound headache, CNN reported.
Currently, withdrawal therapy is the only treatment for rebound headaches, sometimes along with physical therapy or preventative medications such as anticonvulsants, antidepressants, beta blockers and calcium channel blockers to help control withdrawal pain, or injections of Botox or antibodies to prevent migraines.
However, there's been ongoing debate about whether preventative treatments help patients undergoing withdrawal therapy for rebound headaches, CNN reported.
In this new study, researchers examined the effectiveness of withdrawal therapy alone, withdrawal with preventatives, or preventatives alone in reducing headache days per month.
All three approaches were effective, but withdrawal plus preventive medicine led to the largest reductions in headache and migraine days, days with short-term medication use and days with headache pain intensity, CNN reported.
The study, published in the journal JAMA Neurology, also found that patients who withdrew from pain medications with the help of preventatives were much more likely to be cured of their medication overuse headaches than patients who used preventatives or withdrawal alone.
"We were surprised of the study results and the excellent adherence to the treatment," Jensen told CNN. "We now recommend withdrawal and early start of preventive treatment."