Equitable access to safe and effective vaccines is critical to ending the COVID-19 pandemic, so it is hugely encouraging to see so many vaccines proving and going into development, says the World Health Organization.
WHO is working tirelessly with partners to develop, manufacture and deploy safe and effective C-19 vaccines.
Safe and effective vaccines are a game-changing tool: but for the foreseeable future we must continue wearing masks, cleaning our hands, ensuring good ventilation indoors, physically distancing and avoiding crowds.
Being vaccinated does not mean that we can throw caution to the wind and put ourselves and others at risk, particularly because research is still ongoing into how much vaccines protect not only against disease but also against infection and transmission.
But it’s not vaccines that will stop the pandemic, its vaccination. “We must ensure fair and equitable access to vaccines, and ensure every country receives them and can roll them out to protect their people, starting with the most vulnerable,” WHO said.
The impact of COVID-19 vaccines on the pandemic will depend on several factors. These include the effectiveness of the vaccines; how quickly they are approved, manufactured, and delivered; the possible development of other variants and how many people get vaccinated
Whilst trials have shown several COVID-19 vaccines to have high levels of efficacy, like all other vaccines, COVID-19 vaccines will not be 100% effective. WHO is working to help ensure that approved vaccines are as effective as possible, so they can have the greatest impact against the pandemic.
Scientists around the world are developing many potential vaccines for COVID-19. These vaccines are all designed to teach the body’s immune system to safely recognize and block the virus that causes COVID-19.
Is the vaccine safe for children?
Vaccines are usually tested in adults first, to avoid exposing children who are still developing and growing. COVID-19 has also been a more serious and dangerous disease among older populations.
Now that the vaccines have been determined to be safe for adults, they are being studied in children. Once those studies have been completed, we should know more and guidelines will be developed.
In the meantime, make sure children continue physical distance from others, clean their hands frequently, sneeze and cough into their elbow and wear a mask if age appropriate.
How Vaccines compare
AstraZeneca-University of Oxford/Covishield
On November 23, 2020 AstraZeneca and the University of Oxford announced high-level results from an interim analysis of their COVID-19 vaccine, AZD1222. The analysis was from the trials in the UK and Brazil and demonstrated efficacy of up to 90%.
The vaccine was effective at preventing COVID-19, with no hospitalizations or severe cases in people receiving it. There were a total of 131 COVID-19 positive cases in the interim analysis group. One dosing regimen was given at a half dose and demonstrated 90% efficacy, followed by a full dose at least one month apart. Another dosing regimen demonstrated 62% efficacy when given two full doses at least one month apart. The combined analysis showed average efficacy of 70%. The AstraZeneca vaccine can be stored, transported and handled at normal refrigerated conditions, about 2-8 Celsius for at least six months and administered within existing healthcare settings.
On March 25, 2021, AstraZeneca released primary analysis that the vaccine demonstrated 76% efficacy against symptomatic COVID-19, 100% efficacy against severe or critical disease and hospitalizations, and 85% efficacy against symptomatic COVID-19 in people 65 years and older.
The AstraZeneca and University of Oxford’s vaccine uses technology from an Oxford spinout company, Vaccitech. It deploys a replication-deficient chimpanzee viral vector based on a weakened version of a common cold virus (adenovirus) that causes infections in chimpanzees. It contains the genetic materials of the spike protein. After vaccination, the cells produce the spike protein, stimulating the immune system to attack the SARS-CoV-2 virus.
The COVID-19 vaccine developed by AstraZeneca and the University of Oxford has been linked to blood clots. More than a dozen European countries have halted distribution of the AstraZeneca-Oxford vaccine as a result. To date, there have been about 222 suspected blood clotting cases in Europe with more than 30 deaths linked to the AstraZeneca-Oxford vaccine, out of 34 million vaccinations. In these cases, the clots are pulmonary embolism, deep vein thrombosis (DVT) or thrombocytopenia. Normal side effects that go off in a day or two include headache, sore arm, fever and joint pains.
Type: Adenovirus-based
Doses: 2, 10-12 weeks apart
Efficacy: Currently about 80% overall.
Variants: At least one study finds it has little effect against the South African variant, but appears effective against UK and Brazilian variants.
Russia’s Sputnik V Vaccine
Origins
Around November 11, 2020 Russia’s National Research Center for Epidemiology and Microbiology, which Russia authorized for use in August—ahead of even beginning a Phase III trial—claimed had an efficacy rate of 92% after the second dose. It was based on a first interim analysis 21 days after the first injection during the ongoing Phase III study. On November 24, the organization claimed 95% efficacy based on new preliminary data. On December 14, 2020, they reported efficacy of 91.4%. It also offered to share one of its two human adenoviral vectors with AstraZeneca to increase the efficacy of the AstraZeneca vaccine.
Russia’s Gamaleya research institute appears to be focused on potentially marketing their vaccine worldwide. Even the name of the vaccine has emphasized the idea of a race. No serious side effects have been reported, apart from joint pains and headaches. Chills, fever, arthralgia, myalgia, asthenia, general discomfort and headache are among the short term reactions listed after obtaining the Sputnik vaccine. There are also the occasional enlarged regional lymph nodes which can be expected after the Sputnik V jab.
On February 2, 2021, The Lancet published Phase III data demonstrating a 91.6% efficacy against the original strain of the virus.
Type: Adenovirus-based
Doses: 2, four weeks apart
Efficacy: 91.6%
Variants: Unknown. Clinical trial data was largely conducted in Russia prior to the emergence of major variants.
Sinopharm Vaccine
Origins: In early 2020, the Beijing Institute of Biological Products created an inactivated coronavirus vaccine called BBIBP-CorV. Clinical trials run by the state-owned company Sinopharm showed that it had an efficacy rate of 79 percent. China approved the vaccine and soon began exporting it to other countries. A large multi-country Phase 3 trial has shown that 2 doses, administered at an interval of 21 days, have an efficacy of 79% against symptomatic SARS-CoV-2 infection 14 or more days after the second dose. Vaccine efficacy against hospitalization was 79%. The incidence of adverse effects from Sinopharm’s two inactivated COVID-19 vaccines is 1.06 percent, according to a report based on emergency use of the two vaccines in China on more than 500,000 people as of December 1, which is far lower than the phase II clinical trial results. Among the 519,543 people who had accepted the vaccines, no serious side effects were reported, proving the safety of the vaccines. Pain and headache are the most common side effects. Redness, swelling, induration and pruritus are occasional reactions while erythema is a rare reaction soon after the jab.
Headache, fever, fatigue, myalgia, arthralgia, cough, dyspnea, nausea, diarrhea, pruritus, dizziness, anorexia, vomiting, oropharyngeal pain, dysphagia, running nose, constipation and hypersensitivity are among the common and rare reactions expected later after obtaining the Sinopharm vaccine.
Type: Inactivated Coronavirus
Doses: 2, four weeks apart
Efficacy: 86%
Variants: Said to be effective against most variants.
