Get vaccinated. If you choose not to, here’s what to expect if you are hospitalized for a serious case of COVID-19.

Good evening. I’m Karen Kaplan, and it’s Tuesday, Aug. 31. Here’s the latest on what’s happening with the coronavirus in California and beyond.

The results may help engineers develop a way to inject drugs without needles. Squirting a jet of water through a drop of liquid may sound like idle fun, but if done precisely, and understood thoroughly, the splashy exercise could help scientists identify ways to inject fluids such as vaccines through skin without using needles.

A study in mice which is forthcoming in the journal "Proceedings of the National Academy of Sciences" shows one gene is critical to regulating sperm motility.

A key amino-acid change might underlie the coronavirus variant’s ferocious infectivity. As the world grapples with the hyper-infectious Delta coronavirus variant, scientists are racing to understand the biological basis for its behaviour.

According to the White House, more than 200 million eligible Americans have received at least one dose of a COVID-19 vaccine.

Researchers from MIT, the McGovern Institute for Brain Research at MIT, the Howard Hughes Medical Institute, and the Broad Institute of MIT and Harvard have developed a new way to deliver molecular therapies to cells. The system, called SEND, can be programmed to encapsulate and deliver different RNA cargoes, potentially provoking less of an immune response than other delivery approaches.

Early administration of the antiparasitic drug ivermectin didn't significantly shorten time to clinical improvement in 400 adults mildly ill with COVID-19, a clinical trial today in JAMA finds.

The U.S. health care system ranked last among 11 wealthy countries despite spending the highest percentage of its gross domestic product on health care, according to an analysis by the Commonwealth Fund. Researchers behind the report surveyed tens of thousands of patients and doctors in each country and used data from the Organization for Economic Cooperation and Development and the World Health Organization (WHO).

California is implementing what it calls the "first in the nation" requirement that health care workers statewide be vaccinated against COVID-19. The state is currently experiencing its fastest increase in coronavirus cases since the onset of the pandemic, with case rates "increasing ninefold in the last two months," according to the new order from the California Department of Public Health.

This year, it's estimated that more than 100,000 Americans will be diagnosed with melanoma, the most serious form of skin cancer. But there's encouraging news in the battle against the disease, in the form of revolutionary new ways to screen for it.

Men who ejaculate more often have a lower risk of developing prostate cancer, a new study finds. Researchers from Harvard University analyzed data from nearly 32,000 men and found that ejaculating at least 21 times a month cut the risk of developing the cancer by one-third.

A team of doctors in Saudi Arabia has separated a Yemeni baby from her parasitic twin, authorities said, marking their 50th successful operation on conjoined twins. Aisha Ahmed Saeed was born fully developed but with an extended pelvis area and an extra pair of lower extremities, the Saudi English-language Arab News daily reported.

Researchers are challenging widely accepted recommendations that advise mothers to wait at least two years after giving birth to become pregnant again. While these recommendations are designed to reduce the risk of complications like preterm birth and small birth weight, a new study finds that this wait time may not be necessary for all.

Breakthrough cases of COVID-19 are often milder — here's what's commonly experienced

Contrary to myths circulating on social media, COVID-19 vaccines do not cause erectile dysfunction and male infertility. What is true: SARS-CoV-2, the virus that causes COVID-19, poses a risk for both disorders. Until now, little research has been done on how the virus or the vaccines affect the male reproductive system. But recent investigations by physicians and researchers here at the University of Miami have shed new light on these questions.

People who have recovered from COVID-19 tend to score significantly lower on an intelligence test compared to those who have not contracted the virus, ...