I WOULD like to suggest shortening the spacing of AstraZeneca (AZ) vaccine doses from 12 to eight weeks.
There is data to suggest that several variants are responsible for the currently large surge in Covid-19 cases in Malaysia.
It is also a known fact that two doses of Pfizer-BioNTech and AZ vaccines offer better protection and prevent hospital admission against the Delta variant.
In the United Kingdom, the country’s most vulnerable are being offered the second dose of AZ earlier than 12 weeks because of the rising cases of Covid-19 due to the Delta variant. The UK government has also extended its lockdown by another month because of surging cases due to the Delta variant.
Malaysia should reconsider its spacing of the second dose of AZ vaccine and shorten it from 12 weeks to eight weeks even though the 12-week interval may give a stronger immune response. However, earlier protection against the more transmissible and deadlier Delta variant should be considered, especially for the elderly and those with comorbidities. Those vaccinated with the Pfizer-BioNTech are not affected since their doses are already spaced three weeks apart.
The health authorities should continue to conduct more sequencing, especially among large clusters, to determine the spread of Delta and other variants such as Alpha (originated from Brazil), Beta (originated from South Africa), and etc.
EMERITUS PROFESSOR DATUK DR LAM SAI KIT
Research Consultant, UM Senior Fellow, Academy of Sciences Malaysia