Tag: Weaker

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Health

Pfizer-BioNTech’s vaccine will get barely weaker over time, firm knowledge exhibits, however stays robust in stopping extreme illness.

Pfizer-BioNTech’s vaccine gets slightly weaker over time, company data shows, but remains strong in preventing severe disease.

The Pfizer-BioNTech vaccine’s effectiveness wanes slightly over time, according to newly released data from the companies, but remains strong in preventing severe disease. With coronavirus cases surging again in many states, the findings may influence the Biden administration’s deliberations about delivering a booster shot.

The vaccine had a sky-high efficacy rate of about 96 percent against symptomatic Covid-19 for the first two months, the study showed, but then declined about 6 percent every two months after that, falling to 83.7 percent after six months. Against severe disease, its efficacy held steady at about 97 percent. The data was posted online on Wednesday and has not been published in a scientific journal.

Despite the decline, the data confirm that the vaccine gives potent protection against Covid-19. Still, the study raises questions about how much protection two doses will provide in the months to come. Adding to these concerns is the rise of the Delta variant, which makes vaccines somewhat less effective against infection. The variant became dominant only after the study ended. But recent studies have also shown that vaccines remain strongly protective against the worst outcomes of Covid-19 caused by the Delta variant.

The findings come from 42,000 volunteers in six countries who participated in a clinical trial that Pfizer and BioNTech began last July. Half of the volunteers got the vaccine while the other half got a placebo. Both groups received two shots spaced three weeks apart. The researchers compared the number of people in each group who developed symptoms of Covid-19, which was then confirmed by a P.C.R. virus test.

When the companies announced their first batch of results, the vaccine showed an efficacy against symptomatic Covid-19 of 95 percent. In other words, the risk of getting sick was reduced by 95 percent in the group that got the vaccine compared to the group that got the placebo.

That result — the first for any Covid-19 vaccine — brought an exhilarating dose of hope to the world in December when it was riding what had been the biggest wave of the pandemic. Since then, the Pfizer-BioNTech vaccine has made up the majority of shots that Americans have received, with more than 191 million doses given so far, according to the Centers for Disease Control.

After the first analysis, the Pfizer and BioNTech researchers continued to follow the volunteers. The research became more challenging as time passed, because volunteers who got the placebo could ask to get the vaccine once it was authorized in their country.

Understand the State of Vaccine Mandates in the U.S.

For the new study, the researchers followed the volunteers for six months after vaccination, up to a cutoff date of March 13. Looking over that entire period, the researchers estimated the vaccine’s efficacy at 91.5 percent against symptomatic Covid-19. (The study did not measure the rate of asymptomatic virus infections.)

But within that period, the efficacy did gradually drop. Between one week and two months after the second dose, the efficacy was 96.2 percent. In the period between two and four months, the efficacy fell to 90.1 percent. And between four months and six months, the efficacy hit 83.7 percent.

Each estimate came with a margin of uncertainty. But over the six months of the trial, there was a clear decline in efficacy.

The new study comes on the heels of data from Israel suggesting that the Pfizer-BioNTech’s protection may be waning there. But experts have pushed back against a rush to approving a booster there. The data have too many sources of uncertainty, they say, to make a precise estimate of how much effectiveness has waned. For example, the Delta-driven outbreak hit parts of the country with high vaccination rates first and has been hitting other regions later. “Such an analysis is still highly uncertain,” said Doron Gazit, a physicist at Hebrew University who analyzes Covid-19 trends for the Israeli government.

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Business

Toyota gross sales bounce, however G.M. and Ford’s rebounds are weaker.

Toyota sales jump, but G.M. and Ford’s rebounds are weaker.

General Motors saw a slight increase in auto sales in North America in the first quarter, but operations continue to be hampered by a shortage of computer chips.

GM announced Thursday that it had sold 642,250 cars and light trucks in the first three months of the year, up just 4 percent, although sales slowed sharply a year ago when the coronavirus pandemic hit.

In contrast, Toyota Motor saw a strong increase in sales compared to the previous year. The Japanese company reported that North American sales rose 22 percent to 603,066 cars and light trucks in the first three months of 2021. Sales in March were a record high for the month.

Toyota’s big leap helped it outperform the Ford Motor, which was also hit by the semiconductor shortage. Ford’s sales rose just 1 percent to 521,334 in the first quarter. Stellantis – the company formed through the merger of Fiat Chrysler and France’s Peugeot SA – reported that sales in the US rose 5 percent in the first quarter.

Both Ford and GM saw significant sales increases from individual customers at dealerships, while sales declines were reported from fleet operators such as car rental companies and governments.

GM and Ford had to shut down or slow down production at a handful of plants. GM has resorted to manufacturing some vehicles with no parts using computer chips to install those components prior to sale if supply improves.

In a statement, GM hoped its strategy of building cars without some components would help “quickly meet highly anticipated customer demand later this year.”

This approach to automobile construction “underscores the dire nature” of semiconductor shortages, said Garrett Nelson, an analyst at CFRA Research, in a report. “One of the key questions is how much better the recovery in US auto sales can be from here.”

The chip shortage is reflected in GM’s unusually low inventory of 334,628 vehicles. That is around 76,000 fewer than at the end of the fourth quarter and half of the vehicles that dealers had in stock a year ago. Ford’s inventory was 56,100 lower than at the end of 2020.

GM’s weak sales were limited to the Chevrolet brand, whose sales fell 2 percent in the first quarter. This included a 13 percent drop in sales for its full-size Silverado pickup, a key profit maker for the company. Buick, Cadillac, and GMC brands had strong sales for the quarter.

Toyota also reported a drop in sales of its full-size pickup, the Tundra. However, the decline was more than offset by strong sales increases in the sport utility vehicles and cars RAV4, Highlander and 4Runner of the luxury brand Lexus.

Also on Thursday, Honda Motor announced that sales in North America rose 16 percent to 347,091 vehicles in the first quarter.

Categories
Health

Her Eyelid Drooped and She Saved Getting Weaker. What Was Going On?

Her Eyelid Drooped and She Kept Getting Weaker. What Was Going On?

Three weeks later when she returned to her doctor, the patient still had not received the test. And now she had a new problem: her mouth felt weak. It was difficult to talk; Her voice was different. At the end of a short conversation, their words were reduced to whispers. She couldn’t smile and she couldn’t swallow. Sometimes when she drank water it came from her nose rather than her throat. It was strange. And scary.

Chen wasn’t there so she saw a colleague, Dr. Abhirami Janani Raveendran, who was also an intern. Raveendran had never seen MG either, but knew it could affect the muscles of the mouth and throat. She asked the patient to have a blood test and sent Keung a message informing him of the patient’s troublesome new symptoms and the possible diagnosis.

When Keung saw the news, he was alarmed. He agreed that these symptoms made myasthenia gravis a likely diagnosis. And a dangerous one: patients with MG can lose strength in the muscles of the throat and diaphragm and become too tired to breathe. He called the patient. He noticed that her voice was nasal and thin – signs of muscle weakness. She said she had no difficulty breathing, but Keung knew that could change. So he told her to go to the hospital immediately. He frightened her. He wanted it.

After the patient received Keung’s urgent call, her daughter drove her to the emergency room at Yale New Haven Hospital and she was placed in the kneeling unit. This is the section for patients who are not sick enough to need the intensive care unit but may get to this point shortly. A technician would come in every few hours to measure the strength of her breathing. If it got too low, she would have to go to intensive care and maybe land on a breathing apparatus.

Keung wasn’t sure if the patient had myasthenia. Her eyelid was always droopy, her vision always double. With MG, he would expect these symptoms to worsen after using the muscle and improve after resting. And MG usually affected the muscles closest to the body. He would expect her shoulders to be weak, not her hands. Despite his uncertainty, he decided to start treatment for MG. He didn’t want to risk her getting any weaker. She was given high-dose steroids and intravenous immunoglobulins to suppress the parts of the immune system that attack the connection between her nerves and muscles.

The next day, Keung did a test that showed if the patient had MG. In the repeated nerve stimulation test, a tiny electrode is placed over the muscle, in this case the abductor digiti minimi, the muscle that moves the little finger. A series of small (and uncomfortable) shocks are delivered in rapid succession, causing the muscle to contract. In someone with normal nerves and muscles, every identical shock results in identical muscle contraction. In this patient, however, the first shocks produced weak contractions, and then they became even weaker. This charge is characteristic of MG. The blood test that Chen asked her to do was done at the hospital. It was positive. She had myasthenia gravis.