How does each of the available Covid-19 vaccines work?
Once the vaccine is injected, the mRNA is taken up by the macrophages near the injection site and instructs those cells to make the spike protein. The spike protein then appears on the surface of the macrophages, inducing an immune response that mimics the way we fight off infections and protects us from natural infection with SARS-CoV-2. Enzymes in the body then degrade and dispose of the mRNA. No live virus is involved, and no genetic material enters the nucleus of the cells.
Although these are the first mRNA vaccines to be broadly tested and used in clinical practice, scientists have been working on mRNA vaccines for years. And despite this wonderful parody piece. opens in new tab saying that the technology is “obvious,” in fact the breakthrough insight that put the mRNA inside a lipid coating to prevent it from degrading is quite brilliant — and yes, this may be the first time the New England Journal of Medicine has referenced a piece in The Onion. (Last reviewed/updated on 11 Jan 2021)
How should early side effects be managed?
Analgesics and antipyretics such as acetaminophen or ibuprofen are effective in managing post-vaccine side effects including injection-site pain, myalgias, and fever. However, the CDC does not recommend prevaccine administration of these drugs, as they could theoretically blunt vaccine-induced antibody responses.
Because of the small risk of anaphylaxis, sites that administer the vaccines must have on hand strategies to evaluate and treat these potentially life-threatening reactions. The CDC has issued recommendations on how sites should prepare. opens in new tab. (Last reviewed/updated on 11 Jan 2021)
How long will the vaccines work? Are booster doses required?
Since the vaccines have been tested only since the summer of 2020, we do not have information about the durability of protection. Data from the phase 1 trial of the Moderna vaccine suggested that neutralizing antibodies persisted for nearly 4 months. opens in new tab, with titers declining slightly over time. Given the absence of information on how long the vaccines will be protective, there is currently no specific recommendation for booster doses. (Last reviewed/updated on 11 Jan 2021)
Do the vaccines prevent transmission of the virus to others?
Many commentaries on the results of the vaccine clinical trials cite a lack of information on asymptomatic infection as a limitation in our knowledge about the vaccines’ effectiveness. Indeed, this is a theoretical concern, since up to 40% of people who get infected with SARS-CoV-2 have no symptoms but may still transmit the virus to others.
Nonetheless, there are several good reasons to be optimistic about the vaccines’ effect on disease transmission. First, in the Moderna trial. opens in new tab, participants underwent nasopharyngeal swab PCR testing at baseline and testing at week 4, when they returned for their second dose. Among those who were negative at baseline and without symptoms, 39 (0.3%) in the placebo group and 15 (0.1%) in the mRNA-1273 group had nasopharyngeal swabs that were positive for SARS-CoV-2 by RT-PCR. These data suggest that even after one dose, the vaccine has a protective effect in preventing asymptomatic infection.
Second, findings from population-based studies now suggest that people without symptoms are less likely to transmit the virus to others. Third, it would be highly unlikely in biological terms for a vaccine to prevent disease and not also prevent infection. If there is an example of a vaccine in widespread clinical use that has this selective effect — prevents disease but not infection — I can’t think of one!
Until we know more, however, we should continue to emphasize to our patients that vaccination does not allow us to stop other important measures to prevent the spread of Covid-19. We need to continue social distancing, masking, avoiding crowded indoor settings, and regular hand washing. (Last reviewed/updated on 11 Jan 2021)
Join CNET during CES 2021 for talks with three medical luminaries to discuss what we’ve gained — and need to fix — with telehealth over a turbulent pandemic year.
Messenger RNA—or mRNA—vaccines have been in development for decades, and are now approved for use against COVID-19. Here’s how they work and what you should know about them. Visit https://www.jhsph.edu/covid-19 for even more resources.
Hip fracture is an iconic bugaboo of old age. It is a chronic condition in the sense that its complications, such as Depression, blood clots and pneumonia often extend long beyond the healing process.
Predisposing factors include old age and associated risk factors like osteoporosis, sarcopenia (loss of muscle mass and strength), poor vision, poor balance and hazards in the home.
FALLING is the usual agency that produces the fracture. At the risk of being ostracized, I will point out that thousands of injuries sustained by walking or tripping over dogs (and cats) occur every year.
In my small “hilltop” group of friends, there was 1 fatality, 1 shoulder fracture-dislocation, 1 hip fracture, and 0 acknowledgements of animal causation. Members of the family are immune to blame.
Treatment of hip fracture involves surgery with pins, or the more cost-effective Hip replacement. PREVENTION is critical. Osteoporosis must be prevented by exercise, Calcium, vitamin D, and avoidance of certain medication like Corticosteroids.
Balance should be developed by exercises. Vision problems, such as cataracts,should be corrected. Muscle mass should be preserved by diet and exercise, and the home cleared of throw-rugs and obstacles removed.
Just yesterday, a friend wearing socks (reducing friction?) fell down some stairs after stepping over a dog-gate. She is scheduled to have her elbow pinned. Have I mentioned SLEEP, DIET and EXERCISE RECENTLY?
Human Papillomavirus, HPV, is a very successful Virus, from the microbial standpoint. It has been around for a long time, specializes in Humans, kills many fewer than it infects and becomes a chronic disease, even if 90% of infections resolve spontaneously within 2 years.
HPV is a DNA Virus. Most of the strains, if they persist, become harmless nuisances, and cause “Verruca Vulgaris”, the common wart of the skin. The voicebox and windpipe area is rarely targeted, but warts can produce problems there because of the location. Non-malignant genital warts can also occur with certain serotypes.
A few members of the HPV family have evolved to generate premalignant lesions that can develop into CANCER. These strains are spread by Sexual contact. In Women, the CERVIX of the Uterus or the vagina are often involved. The anal area, back of the throat and the Lung are occasional sites in both sexes. In Men, the Penis is targeted.
Cancer is generally a delayed effect that occurs after a long infection. Some HPV strains, such a 16 and 18, have evolved to suppress the p53 gene, an ONCOGENE which protects us from malignant progression. Without this protection, a chance cancerous mutation can grow without restraint. Since HPV can invade only the deeper basal stem cells in the skin or lining mucous membranes, some minor trauma or break in the surface is needed to allow Viral entry.
If antibodies are present, the Virus is intercepted, and infection doesn’t take place. This discovery made Immunization with the Cancer-producing strains attractive. It is also why the immunization is recommended in Childhood, before Sexual activity begins. Immunization after the HPV is already inside the body is Ineffective.
The Virus is already in the Nucleus of infected cells and protected from the immune response. The recommendation is to get the immunization in childhood, and use condoms.
Every year, as millions of people around the world forge new resolutions to eat healthier and lose weight, US News & World Report releases a conveniently timed ranking of the best diets. A panel of experts in obesity, nutrition, diabetes, heart disease, and food psychology rigorously rate each of 39 diets on seven criteria:
- Likelihood of losing significant weight in the first 12 months
- Likelihood of losing significant weight over two years or more
- Effectiveness for preventing diabetes (or as a maintenance diet)
- Effectiveness for preventing heart disease (or for reducing risk for heart patients)
- How easy it is to follow
- Nutritional completeness
- Health risks (like malnourishment, too-rapid weight loss, or specific nutrient deficiencies)
1. Mediterranean diet
Emphasis on fruits, veggies, whole grains, olive oil, beans, nuts, legumes, fish and other seafood. Eggs, cheese, and yogurt can be eaten in moderation. Keep red meats and sugar as treats.
2. DASH (dietary approaches to stop hypertension) diet — TIE
Eat lots of fruits, veggies, lean protein, whole grains, and low-fat dairy. Avoid saturated fats and sugar.
2. Flexitarian diet — TIE
Be a vegetarian most of the time. Swap in beans, peas, or eggs for meats, and consume plenty of fruits, veggies, and whole grains. You can look up more details because there’s actually a full meal plan involving breakfast, lunch, dinner, and two snacks to add up to a total 1500 calories per day. But feel free to also just swap in flexitarian meals ad hoc.
4. Weight Watchers
The first actual paid program on the list, WW uses a points system to guide dieters towards foods lower in sugar, saturated fat, and overall calories while consuming slightly more protein. There are a variety of paid WW plans, with the lowest being about $20 per month.
5. Mayo Clinic diet — TIE
A two-part system, with part one (‘Lose it!’) involving adding a healthy breakfast (i.e. fruits, veggies, whole grains, healthy fats) plus 30 minutes of exercise per day. You’re not allowed to eat while watching TV or consume sugar except what’s naturally found in fruit. Meat is only allowed in limited quantities, as is full-fat dairy. The second phase (‘Live it!’) is basically the first phase but with more flexibility. You aren’t realistically going to cut out sugar forever, and the Mayo Clinic diet acknowledges that. So the long term plan involves lots of whole grains, fruits, veggies, and healthy fats. Less saturated fats and sugar.