COVID-19 Vaccine Information

In light of the recent approvals and deployment of COVID-19 vaccines across the world, we know that you have many questions about what it means for approvals and social restrictions. Access to a vaccine for the novel coronavirus (COVID-19) is crucial to curbing the spread of COVID-19 and restarting economies globally.

The World Health Organization applies a procedure to assess the quality, safety and efficacy of various vaccines before recommending them to countries and UN agencies. CARPHA endorses this process and recommends these vaccines, as it applies the highest international standards, and ensures that manufacturers are following good manufacturing practices, and that they remain accountable for the safety and quality of the vaccines.

The Caribbean Public Health Agency urges the reliance on existing scientific evidence to support public health policy, particularly as it relates to maintaining public health measures and social restrictions until countries have ensured that a sufficient proportion of the population is immune to SARS-CoV-2 virus. The CARPHA CRS collaborates with the World Health Organization and the Pan American Health Organization in terms of the recognition of regulatory authorities used in its procedure for the verification of COVID-19 products that have been assessed by trusted authorities and recommended for emergency use authorization.

For COVID-19 vaccines that require two doses, the first initiates the immunity-building step but the second is needed to complete the process (boost the system for a response when exposed to the virus). Between the first and second dose, full immunity is not assured, so persons are still at risk of infection. In addition, past data indicate that it requires another 2 weeks after the second dose for full immunity. Persons who have received 1 or 2 doses should still follow the public health precautions of social distancing, hand-hygiene (washing & sanitizing) and wearing of facial masks, until public health officials in your country state otherwise. Only when enough persons are vaccinated can these be relaxed.

Vaccine developers are not yet sure of how long immunity will last after vaccination against COVID-19, or after infection with SARS-CoV2, and are still studying this aspect. Once the information is available through monitoring of trial participants, the vaccine information will be updated to indicate if the vaccine will be needed annually, or otherwise. In the meantime, persons who have been vaccinated (complete vaccine schedule) are advised to maintain the social restrictions to reduce the risk of exposure to the virus.

It is recommended that social restrictions may be relaxed when herd immunity is achieved at a national level. For SARS-CoV-2, this has been estimated when approximately 70-90% of the population acquire immunity to break the chain of transmission. Until then, persons who have been vaccinated should continue with the ascribed social restrictions of hand-washing, social distancing, and face masks, as others may not be immune.

At this time, the evidence is not clear on the interchangeability of the vaccines made by different developers, including those made using the same vaccine platform. Some national authorities have introduced interchangeability as a contingency in the event the second dose of the initial brand of vaccine administered is not available when the patient returns, rather than send the patient away without it. CARPHA advises Member States to monitor the scientific evidence as it relates to interchangeability, and be guided accordingly.

CARPHA’s Caribbean Regulatory System (CRS) will apply its reliance procedure to verify vaccines with emergency use authorization granted by stringent regulatory authorities of reference. To support regional surveillance of vaccine safety, the CRS will support reporting of adverse events following immunization (AEFIs) and reporting of substandard / falsified / unregistered COVID-19 vaccines found in Member States.

Vaccine development is ongoing in different countries of the Americas, including Brazil and Cuba. Vaccines that are developed and/or approved for use in these countries may be considered by the national authorities of CARPHA/ CARICOM Member States with the capacity to undertake comprehensive assessments of the quality, efficacy and safety of the vaccines. At this time, the CARPHA CRS does not rely on assessments by Brazil or Cuba for emergency use review procedure for COVID-19 vaccines. The CRS uses regulatory reliance on assessments by national regulatory authorities to make recommendations to Member States. The selection of the national authorities are based on those recognized for the assessment of biologics (biosimilars, vaccines) by the World Health Organization. At this time, the CARPHA CRS will accept these vaccines for review once they have been approved for emergency use listing by the World Health Organization, or approved for emergency use authorization by one of the following regulatory authorities: Medicines and Healthcare Products Regulatory Agency (UK), European Medicines Agency (EMA), Therapeutic Goods Administration (Australia), Health Canada, United States Food and Drug Administration, or Swissmedic.

National regulatory authorities vary in their regulatory capacity. The given country may have a system for the direct and comprehensive assessment of vaccines (including inspections of manufacturers) prior to market entry. For countries with the capacity to assess vaccines directly, this approach is feasible. However, for countries that do not have the in-house capacity to assess vaccines directly, regulatory reliance on trusted regulatory authorities is recommended. The selection of a trusted authority by CARICOM Member States should be guided by the PAHO / WHO’s assessment of national regulatory authorities for the relevant product type, as regulators that are recognized for assessment of medicines may vary from those that are recognized for the assessment of vaccines or test kits.