Latest news with #Chin-Hong
23-05-2025
- Health
What we know about the safety, efficacy of mRNA vaccines amid recent scrutiny
Over the last several days, the safety and efficacy of messenger RNA, or mRNA, vaccines have come under intense scrutiny. On Tuesday, the U.S. Food and Drug Administration announced plans to limit access to future COVID-19 shots -- two of which are mRNA vaccines -- to those aged 65 and older or with high-risk conditions. The agency will require further scientific trials to greenlight the shots for younger age groups. The agency also sent letters to both Moderna and Pfizer last month telling them to expand the warning labels on their mRNA COVID-19 vaccines to broaden the people who may be impacted by the risk of heart inflammation as a possible side effect. Infectious disease experts told ABC News that mRNA and mRNA vaccines have been studied for decades, the vaccines are safe and effective, and that the shots were instrumental in saving lives during the COVID-19 pandemic. 'Here's the bottom line: mRNA vaccines for COVID, according to estimates from Yale School of Public Health, saved 3.2 million lives,' Dr. Peter Hotez, a professor of pediatrics and molecular virology at Baylor College of Medicine in Houston, told ABC News. 'So instead of 1.2 million Americans who lost their life because of COVID, it would have been a 4.4 million,' he added. 'So, I think it's unfortunate that anti-vaccine activists target mRNA vaccines like they do, but it is a good technology.' What is mRNA? mRNA was discovered independently by two teams in 1961 including French and American molecular biologists. Dr. Peter Chin-Hong, a professor of medicine and infectious disease specialist at the University of California, San Francisco, said breakthroughs in developing mRNA vaccines began in the early 2000s, eventually leading to the development of COVID-19 vaccines in 2020. While most vaccines use a weakened or inactivated virus to stimulate an immune response, mRNA vaccines teach the body how to make proteins that can trigger an immune response and fight off an infection. 'The way that it works is that it doesn't even go into the nucleus [of the cell]. It enters the outside of the cytoplasm, or the watery substance outside of the nucleus, and basically instructs the cell to make proteins,' Chin-Hong told ABC News. 'But most importantly, it self-destructs in matter, at the most days, and it dies.' He continued, 'So mRNA goes away, but the products which are the most important thing -- the proteins and antibodies -- remain, and that's why we get protection.' Chin-Hong also addressed another piece of misinformation that has circulated, implying that mRNA vaccines could alter DNA in the nucleus. 'Ou cells can't convert mRNA to DNA because the mRNA doesn't enter the DNA, which is in the nucleus,' he added. How do we know it's safe? Chin-Hong said that during the large-scale clinical trials for COVID-19 mRNA vaccines, in 2020 more than 70,000 people were involved in the Pfizer-BioNTech and Moderna trials combined. Additionally, 37,000 people were involved in Moderna's clinical trials for its RSV vaccine, Chin-Hong said. Researchers found that side effects -- including fever, arm pain and swelling at the injection site -- for the COVID-19 mRNA were like those of traditional, non-RNA vaccines and they had short-term efficacy rates of more than 90%. Additional studies have found that booster safety was consistent with safety reported for primary vaccination. 'There are all these databases that are used to follow reports of people, not only in this country, they experience using vaccines, but also in other countries, many other countries as well,' Chin-Hing said. 'There have been multiple studies since 2020 showing there's no impact in fertility, stroke, all the things that people have worried about.' Hotez said no vaccine technology is perfect, including mRNA technology, but it has its advantages such as being able to be designed more quickly traditional vaccines, allowing them to be deployed quicker. He disagrees with the FDA decision to limit future COVID-19 vaccine shots because COVID has long-term consequences such as long COVID and delayed cardiovascular disease. 'I think there are many younger adults, or those under the age of 65, who are concerned enough about long COVID or downstream heart disease to want to have to be able to get the mRNA vaccine,' he said. What about myocarditis? Questions have swirled around how myocarditis, which is inflammation of the heart muscle, occurs after COVID-19 vaccination. Myocarditis can cause arrhythmias, which are rapid or abnormal heartbeats. It can also cause the heart muscle to weaken, resulting in cardiomyopathy, which affects the heart's ability to pump blood effectively. Cases of myocarditis and pericarditis -- inflammation of the sac that contains the heart -- have been observed rarely after COVID vaccination, according to the Centers for Disease Control and Prevention. When they have rarely occurred, it has been among young adult males, typically between ages 18 and 29, within seven days after receiving the second dose of an mRNA COVID vaccine, the agency says. The FDA, in asking the vaccine companies to expand their warning labels, cited 'new safety information' -- data from one of the agency's safety surveillance systems and a study published in October that followed people who developed myocarditis linked to COVID vaccines. Chin-Hong said the risk of myocarditis is much higher after COVID-19 compared to after vaccination, and that contracting COVID itself is higher. 'The risk of COVID is much higher in general. If you look at it, 22 to 31 cases per million [among] 18 to 29 years old as an example,' he said. 'At the time when these vaccines are used very often in that group is 1,500 per million. So, you're talking about 22 to 31 per million versus 1.500 per million.'
San Francisco Chronicle
14-05-2025
- Health
- San Francisco Chronicle
The worst of avian flu outbreak may be over in California, health officials say
The worst of the H5N1 avian flu outbreak — which began in 2024 and infected thousands of birds and dairy cows and dozens of people in the U.S. — may be over in California, state public health officer Dr. Erica Pan said Tuesday. 'In California, we feel we've gotten through the worst of this,' Pan said during a briefing for medical professionals held by the California Medical Association. 'In fact, we have demobilized the active public health coordination response and will continue to monitor.' The Department of Public Health on Tuesday did not clarify what exactly the demobilization entails. The virus appears to have slowed in California and nationally, though it's unclear if some of that may be related to less surveillance or a scaled-back federal workforce doing less testing and information-sharing with state and local health departments. It may be that the state or nation is in a temporary lull that may pick up again in the fall and winter. This is because wild birds, the source of many infections, migrate north to Alaska and northern Canada to mate in the spring, and return back south in the fall. This may be why there was so much bird flu activity in the U.S. last fall, said UCSF infectious diseases specialist Dr. Peter Chin-Hong. 'We're kind of in a quiet period now,' Chin-Hong said. 'We aren't seeing reports of humans getting infected as much as we did in the earlier part of the year or late part of last year.' As of late last year, California was the epicenter of the U.S. outbreak, with about 70% of cases in dairy cattle and the majority of cases in people. To date, 38 of the total 70 confirmed human cases in the U.S. have been found in California. Most have been among dairy and poultry workers who experienced mild symptoms, with the exception of one Louisiana resident who died, and two young children in the Bay Area who recovered after having mild symptoms and had unknown sources of exposure. In California, the virus among dairy cattle peaked with 766 infected herds in 12 counties as of earlier this month. While avian flu is very deadly in birds, cows usually get milder symptoms and are kept in quarantine for a period of time, tested and released once they test negative. 'The worst thing we can do is forget about it,' Chin-Hong said. 'We need to continue to be vigilant. Just because we're not seeing much now doesn't mean that for the future.'
Japan Times
02-04-2025
- Health
- Japan Times
Once-rare fungal diseases are killing millions in an unprepared world
When most people think of dangerous infections, they picture bacteria or viruses. But for infectious disease specialists like Peter Chin-Hong, one of the most insidious threats lurking in hospitals and clinics today is fungal. Chin-Hong's case list is long: a healthy 29-year-old marathon runner from California's Central Valley whose heart lining was invaded by Coccidioides, a soil-dwelling fungus; a lung transplant recipient coughing up mold nodules — fungal growths scattered throughout his lungs — after stopping antifungal medication; and a 45-year-old woman with poorly controlled diabetes, infected by a black fungus that destroyed part of her face and spread to her brain. Despite multiple surgeries and treatment, she died in the hospital. "These aren't rare anymore,' said Chin-Hong, associate dean and professor of medicine at the University of California, San Francisco. "We're seeing them every day.' Once considered obscure or opportunistic, invasive fungal infections are now surfacing with alarming frequency — and in patients and places doctors never used to worry about. Climate change is expanding the geographic reach of fungi. Medical advances like organ transplants, chemotherapy, and intensive care are saving lives, but they also leave more patients immunocompromised. Even common conditions like diabetes raise the risk of severe fungal disease. An estimated 6.5 million people develop invasive fungal infections each year, with about 2.5 million deaths directly caused by them — roughly twice the global toll of tuberculosis. Many of those deaths are in people with advanced HIV, and experts warn the problem may worsen as funding for global HIV/AIDS programs is pulled back. A surge in AIDS-related illness, they say, could turbocharge the fungal crisis, especially in low-resource settings where diagnostic tools and antifungal treatments are already limited. Adding to the danger is the rise of drug-resistant infections — strains that no longer respond to the limited arsenal of antifungal medications. Candida auris, a newly emerging yeast first seen in 2009, has already triggered deadly outbreaks in hospitals and long-term care facilities. Experts warn that broader resistance could soon outpace the slow development of new drugs. Fungal crisis The World Health Organization warned Tuesday of critical global gaps in the ability to diagnose and treat fungal infections. That includes the dangerously thin pipeline of medicines, with just four new antifungals approved globally over the past decade. Of the nine currently in clinical development, only three have reached the final stage of patient studies. "We can expect few new approvals in the next 10 years,' said Valeria Gigante, who leads the antimicrobial resistance division at WHO in Geneva. More than half of the antifungal candidates in development lack true innovation, limiting their ability to counter emerging resistance, Gigante added. "We always need new ways to kill dangerous fungi,' she said. "Only three of the nine candidates even target the most critical pathogens.' Fungal threats have remained dangerously overlooked, said Justin Beardsley, an infectious diseases doctor and University of Sydney researcher who contributed to both WHO reports. "Fungus is not on anybody's radar,' he said. "It's unobserved and out of control — which means we're not developing mitigations.' He also pointed to growing concern over agricultural antifungal use. "A lot of the new drugs being developed don't have a novel mechanism of action,' Beardsley said. And in many cases, new compounds are introduced faster in agriculture to protect crops from diseases like powdery mildew. "That is just really disheartening for human drug developers — and a little bit worrying for public health, that our new-hope drugs are already going to be getting exposed to a biosimilar agent in the environment and we're going to get resistance.' Another shortcoming is around diagnostics, with the WHO cautioning that even when tests exist to identify deadly fungi, they're often unavailable in low— and middle-income countries. Most rely on well-equipped laboratories and trained personnel. The development of systems to detect invasive fungal infections and determine drug susceptibility is also lagging behind what exists for bacteria, Gigante said. Unseen foe Fungal infections behave differently from bacteria and viruses. They rarely spread person to person. Instead, most come from the environment — moldy soil, decaying plants, airborne spores. Some spores can even travel high into the atmosphere and drift across continents, making them especially hard to track or control. That makes it nearly impossible to fully protect vulnerable patients. UCSF's Chin-Hong said doctors often prescribe preventive antifungal medication to people at high risk, such as those who've had lung or blood stem cell transplants. But the drugs don't cover every type of mold. Mucormycosis — a rare but aggressive infection — is notoriously difficult to treat. "Mucormycosis is probably the scariest one we have,' Chin-Hong said. "If it gets into the lungs, the death rate can be as high as 87%.' The fungus can also invade the sinuses and spread to the brain, with a mortality rate around 50%. It causes tissue to die — cutting off blood flow so antifungal drugs can't reach the infection site. "You have to surgically remove the infected area,' he said. "A lot of times people have their eye taken out because it goes up through the sinus cavity, and there's no good treatment for that.' Resection — surgically removing infected tissue — is sometimes possible in the sinuses or skin. But in the lungs, it's often far more difficult. "The reason lung mortality is so high is because you can't just cut out big chunks of lung,' Chin-Hong said. And even when drugs work, they're often less effective in the very patients who need them most — those with weakened immune systems. "We have agents now,' Chin-Hong said, "but we're running out of them.'
Bloomberg
01-04-2025
- Health
- Bloomberg
Once-Rare Fungal Diseases Are Killing Millions in an Unprepared World
When most people think of dangerous infections, they picture bacteria or viruses. But for infectious disease specialists like Peter Chin-Hong, one of the most insidious threats lurking in hospitals and clinics today is fungal. Chin-Hong's case list is long: a healthy 29-year-old marathon runner from California's Central Valley whose heart lining was invaded by Coccidioides, a soil-dwelling fungus; a lung transplant recipient coughing up mold nodules — fungal growths scattered throughout his lungs — after stopping antifungal medication; and a 45-year-old woman with poorly controlled diabetes, infected by a black fungus that destroyed part of her face and spread to her brain. Despite multiple surgeries and treatment, she died in the hospital.
Yahoo
23-02-2025
- Health
- Yahoo
More than 900 Californians have died from the flu so far this season amid low vaccine rates, state says
More than 900 Californians — including 15 children — have succumbed to the flu this season in what has turned out to be one of the worst surges of the respiratory illness in years, according to a report released Friday by the California Department of Public Health. Most of the influenza victims — 701 — were over 64 years old, which tracks with the conventional notion that the illness disproportionately affects older people. However, the number of children who have died has raised concerns. Four more kids died from the flu during the week ending Feb. 15, increasing the seasonal pediatric death toll by more than a third, according to the report. Read more: Worst flu season in years swamps California: 'Particularly long and difficult' With regard to COVID-19, "we just thought about older adults as getting sick," said Dr. Peter Chin-Hong, an infectious disease specialist and professor of medicine at UC San Francisco. "We have to reset with flu. Because with flu, it's not just the very old, it's also the very young. And they can do very poorly." The 15 children who died from the flu this season includes four teenagers from San Diego. None of the teens — aged 14, 15, 16 and 17 — had received flu shots, according to health officials. 'These recent flu deaths among our youth are tragic and concerning as we head into what historically is the peak of flu season,' Dr. Ankita Kadakia, San Diego County's interim public health officer, said in a statement this month. Vaccination rates have declined, particularly among children, for the flu and other ailments, according to Chin-Hong. Nationally, roughly 58% of children between 6 months and 17 were vaccinated against the flu during the 2020-21 season, declining to about 45% as of late January of this year. "In the world of vaccines, that's like falling off a cliff," Chin-Hong said. The trend is similar in California: 47.7% of California's children have been vaccinated against flu as of late January, the lowest since at least the 2019-20 flu season. Last year at this time, 53.7% of children were vaccinated against flu. The Centers for Disease Control and Prevention recommends everyone 6 months or older get a flu shot — ideally by the end of October to boost protection against the disease during high-circulation winter months. The two types of flu generally circulating now are H1N1 — related to the swine flu strain that caused a flu pandemic in 2009 and 2010 — and H3N2, which "is notorious for just causing more serious illness in general," Chin-Hong said previously. Given how potent this flu season has already proved to be, officials say those who have yet to be vaccinated should consider doing so. While flu activity remains high, it may be decreasing. California public health officials' recent report shows a 3.4% decline in the rate at which flu tests returned positive results at the state's clinical sentinel labs for the week ending Feb. 15, the most recent for which complete data are available. Still, the test positivity rate sits at an elevated 23.3%. COVID-19 and RSV activity is low, health officials said, with positivity rates of 2.3% and 5%, respectively. Chin-Hong said it's not yet clear if the downward trend will hold. "I think it's too early to celebrate," he said, adding that more data points are needed. Flu season in the U.S. typically peaks between December and February, though the virus spreads year-round, according to the CDC. Even if it's on the decline, the virus is known for having a prolonged season, Chin-Hong said. It can run through April and sometimes later in the year. "It's not only the peak that we're worried about," Chin-Hong said. "It's also the breadth of what's happening this year." There were about 500 deaths last season from the flu by this point in time, and 600 the year before, the Mercury News reported. Chin-Hong estimates he hasn't seen a death toll like that of this season in a decade. Times staff writer Rong-Gong Lin II contributed to this report. Sign up for Essential California for news, features and recommendations from the L.A. Times and beyond in your inbox six days a week. This story originally appeared in Los Angeles Times.
