Current evidence indicates that the Oxford/AstraZeneca vaccine is safe and effective and that the benefits of the Oxford/AstraZeneca vaccine in combating the widespread threat of COVID-19 continue to outweigh the risks of side effects, said WHO Country Office, Sri Lanka, Officer in Charge/ Public Health Administrator Dr. Olivia Nieveras in an interview with the Daily News.
“Sri Lanka was one of the first countries to initiate a vaccine rollout which is a commendable achievement,” she said.
Excerpts of the interview:
Q: Sri Lanka received the first shipment of the COVID-19 AstraZeneca vaccines through the international COVAX facility run by the World Health Organization (WHO) in early March. It was reported that the country will receive another batch of vaccines under WHO’s COVAX facility. The World Health Organization has pledged to provide 20 percent of Sri Lanka’s population with the COVID-19 vaccine. Could you update us on the progress?
A: COVAX is a global vaccine initiative co-led by Gavi, the Vaccine Alliance, the World Health Organization (WHO) and the Coalition for Epidemic Preparedness Innovations (CEPI), funded by donations from governments, multilateral institutions and foundations, with UNICEF leading on procurement, logistics, and storage globally. On March 7, 2021, Sri Lanka received the first batch of COVID-19 vaccines from the COVAX facility. This delivery of 264,000 doses was part of the first wave of arrivals that will continue in the coming weeks and months, culminating in 1,440,000 doses arriving through May. The additional doses to cover 20 percent of Sri Lanka’s population will arrive in the second half of 2021. All these doses are donor-funded and provided at no cost to Sri Lanka.
Sri Lanka was one of the first countries to initiate a vaccine rollout, a commendable achievement. To date, the Government has vaccinated over 800,000 people with the first dose of the COVID-19 vaccine.
Q: Initially it was said that the second jab of the AstraZeneca vaccine should be taken one month after the first dose. Of late, what we hear is that the second dose has to be taken after 12 weeks. What is the reason for extending the length of time between doses? Does it indicate that no proper research has been done on its interval?
A: Following the introduction of a vaccine, close monitoring continues to take place to continue assessing how best to use the vaccine for the greatest protective impact. This is because recommendations on best practices may evolve with emerging evidence.
For the Oxford/AstraZeneca COVID-19 vaccine, the recommended schedule is two doses (0.5 ml). The vaccine can be administered with an interval of four to12 weeks. Studies have shown that (1) vaccine efficacy tended to be higher when the interval between doses was longer, and (2) higher antibody levels were observed with increasing the interdose interval. Therefore, it was concluded that longer dose intervals within the four to 12 weeks range are associated with greater vaccine efficacy.
Q: Even after receiving the second dose of the vaccine, can one still get Covid 19?
A: It typically takes a few weeks for the body to build immunity (protection against the virus that causes COVID-19) after vaccination. That means it is possible for a person to become infected with the COVID-19 virus just before or just after vaccination and become ill. This is because the vaccine has not had enough time to provide protection, not because the vaccine was ineffective. Moreover, because no vaccine will have 100 percent efficacy, some persons who are vaccinated with COVID-19 vaccines may not develop sufficient immunity against the disease and, therefore, would remain at risk of contracting the disease. Current evidence shows that the Oxford/AstraZeneca COVID-19 vaccine is extremely effective against severe cases of COVID-19.
Q: It was reported that the COVID-19 vaccination does not work well for African and Brazilian variants. Please explain.
A: The Oxford/AstraZeneca vaccine has been shown in randomized clinical trials in UK and Brazil to be safe and efficacious and has received approval from a number of stringent regulatory authorities. The trial sites did not include sites with B1.351 (first identified in South Africa) circulation but did include B1.1.7.
* A small clinical trial in South Africa concluded that the vaccine is minimally effective at preventing cases of mild to moderate COVID-19 caused by a new viral variant (B.1.351) first identified in South Africa.
* Given the small sample size of the trial and the low-risk nature of the participants (whose median age was 31), the trial was unable to assess efficacy against severe disease or hospitalization, or death, which are the main strategic targets for vaccination. It is now important to determine the vaccine’s efficacy when it comes to preventing more severe illness.
* SAGE reviewed the available evidence on February 8 and recommended proceeding with the vaccine rollout recognizing also for country tailoring and the importance of additional studies to fill critical evidence gaps to drive vaccine policy and vaccine development.
WHO closely monitors the changes reported in the SARS-CoV-2 virus through genomic sequencing. This virus, like other viruses, constantly changes over time. It is important to monitor these changes and their effect on diagnostics, treatment, and vaccines. What we presently know is that the vaccines currently available and in development should provide protection against the various strains of SARS-CoV-2 reported so far. This is because these vaccines elicit a broad immune response and a host of antibodies and cell-mediated immune responses. We need to continue to follow the virus evolution and its potential impact.
Q: What are the WHO approved vaccines against COVID-19?
A: Currently, WHO emergency use listing (EUL) for COVID-19 vaccines has been granted for the Pfizer-BioNTech vaccine, the Oxford/AstraZeneca vaccine, and the Janssen vaccine.
The WHO EUL procedure assesses the suitability of novel health products during public health emergencies. The objective is to make medicines, vaccines, and diagnostics available as quickly as possible to address an emergency while adhering to stringent criteria of safety, efficacy, and quality. The assessment weighs the threat posed by the health emergency and the benefits of the proposed product against any potential risks.
The EUL pathway involves a rigorous assessment of late phase 2 and phase 3 clinical trial data and substantial additional data on safety, efficacy, quality, and risk management. The data is reviewed by independent experts, not by WHO authorities.
Experts from individual national authorities are invited to participate in the EUL review. Once a vaccine has been listed for WHO emergency use, the WHO engages its regional regulatory networks and partners to inform national health authorities of the vaccine and its anticipated benefits based on data from clinical studies to date.
Updated information can be found at the following link: https://www.who.int/teams/regulation-prequalification/eul/covid-19
Q: The European Medicines Agency’s (EMA) which investigated on the AstraZeneca vaccine and thromboembolic events finally declared the vaccine to be safe. What were the committee recommendations?
A: The WHO Global Advisory Committee on Vaccine Safety (GACVS) COVID-19 subcommittee met virtually on March 16 and 19 to review available information and data on thromboembolic events (blood clots) and thrombocytopenia (low platelets) after vaccination with the AstraZeneca COVID-19 vaccine.
Based on a careful scientific review of the available information, the subcommittee came to the following conclusions and recommendations:
* The AstraZeneca COVID-19 vaccine (including Covishield) continues to have a positive benefit–risk profile, with tremendous potential to prevent infections and reduce deaths across the world.
* The available data do not suggest any overall increase in clotting conditions such as deep venous thrombosis or pulmonary embolism following administration of the COVID-19 vaccines. Reported rates of thromboembolic events after the COVID-19 vaccines are in line with the expected number of diagnoses of these conditions. Both conditions occur naturally and are not uncommon. They also occur as a result of COVID-19. The observed rates have been fewer than expected for such events.
* While very rare and unique thromboembolic events in combination with thrombocytopenia, such as cerebral venous sinus thrombosis (CVST) have also been reported following vaccination with the AstraZeneca COVID-19 vaccine in Europe, it is not certain that they have been caused by vaccination. The EMA’s Pharmacovigilance and Risk Assessment Committee has reviewed 18 observed cases of CVST out of a total of more than 20 million people vaccinated with the AstraZeneca vaccine in Europe. A causal relationship between these rare events has not been established at this time.
* The GACVS subcommittee recommends that countries continue to monitor the safety of all COVID-19 vaccines and promote reporting of suspected adverse events.
* The GACVS subcommittee also agrees with the EMA’s plans to further investigate and monitor for these events.
The GACVS COVID-19 subcommittee will continue to review the safety data from all COVID-19 vaccines and update any advice as necessary.
Q: So it is quite safe to go ahead with AstraZeneca vaccine?
A: Current evidence indicates that the Oxford/AstraZeneca vaccine is safe and effective and that the benefits of the Oxford/AstraZeneca vaccine in combating the widespread threat of COVID-19 continue to outweigh the risks of side effects.
Q: Some people in Sri Lanka are still reluctant to get the vaccine despite being advised by the health officials to go ahead with it. Could you brief us on its importance?
A: Vaccines are a global public good: everyone benefits when anyone is vaccinated.
There will be no true health or economic recovery unless all parts of the country and world reduce COVID-19 morbidity and mortality; vaccines are a key part of that.
Developing immunity through vaccination reduces your risk of acquiring the illness because your body already knows how to fight the virus if you’re exposed. Getting vaccinated may also protect the people around you, because if you are protected from getting the disease, you are less likely to infect someone else. This is particularly important to protect people at increased risk for severe illness from COVID-19, such as older people and people with comorbidities.
Q: What are the after effects, if any, of the Covid-19 vaccine?
A: Like any medicine or vaccine, COVID-19 vaccines can cause mild side effects such as fever, headache, tiredness, muscle pain, and/or pain or redness at the injection site. Mild reactions go away on their own within a few days. Severe or long-lasting side effects are extremely rare. Vaccines are continually monitored for safety, to detect rare adverse events.
Following the introduction of a vaccine, close monitoring continues to take place to detect any unexpected adverse side effects and further assess effectiveness among even larger numbers of people, to continue assessing how best to use the vaccine for the greatest protective impact. Therefore, it is important that vaccine recipients inform designated health authorities of any experienced side effects or adverse events.
Q: Can one get back to normal lifestyle after getting both doses? Do we have to continue wearing facemasks while also adhering to hand hygiene practices?
A: Public health and social measures are the foundation of our response to COVID-19. Vaccines are important tools, and vaccination is a key intervention, but by themselves, they will not end the pandemic. As we roll out the vaccines globally, we need to take all necessary measures to prevent the virus from spreading and causing more deaths. We need to stay the course and “do-it-all” and do it better. This means, along with vaccination, we need to continue practising physical distancing, wearing masks, washing our hands with soap, increasing ventilation, avoiding crowds, disinfecting surfaces, and staying home if asked.
Additionally, so far, vaccines appear to be efficacious against developing the disease, but we don’t know their impact on preventing transmission. We need more evidence on this, and ongoing studies will help us answer these questions. Hence, it is important that a person who gets the vaccine continues to take necessary precautions in order to protect everyone in the community. This means continuing to practise physical distancing, wearing masks, washing our hands with soap, increasing ventilation, avoiding crowds, disinfecting surfaces, and staying home if asked.
