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Delayed second jab may have done you good

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5 years ago

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Covishield vaccine induces immunity for at least one year following a single dose

Strong immune responses following either a late second dose or a third dose

by Emme Haddon

In early March 2021, I received my first shot of Covishield but began to get a little worried when the recommended three-month time frame had passed for the second dose with no sign of the promised shipment from India. Finally, in the first week of August, some months later, after what seemed like an interminable wait, I was fortunate enough to secure my second dose of Covishield, along with 490,000 or so others.

The findings of a study of Vaxzevria, the European brand name for the UK’s AstraZeneca vaccine of which the Indian-manufactured Covishield is biologically identical, from the Oxford-led COV001 and COV002 trials by researchers at the University of Oxford, released on June 28, 2021 on the pre-preprint server of the Lancet, demonstrated that antibody levels remain elevated from baseline for at least one year following a single dose.

Furthermore, a 45-week dosing interval between the first and second dose of Covishield, resulted in an 18-fold increase in antibody response, measured 28 days after the second dose. Antibody titers (test determining level of antibodiess in the blood) were four times higher than with a 12-week interval, demonstrating that a longer dosing interval is not detrimental but can derive stronger immunity. The analysis included volunteers aged 18 to 55 years who were enrolled in COV001 and COV002 trials and had received either a single dose or two doses of COVID-19 Vaccine AstraZeneca.

In addition, a third dose of Vaxzevria given at least sixmonths after a second dose, boosted antibody levels sixfold, maintained T cell response and also resulted in higher neutralising activity against the Alpha (B.1.1.7, ‘Kent’), Beta (B.1.351, ‘South African’) and Delta (B.1.617.2, ‘Indian’) variants. Both the late second dose and the third dose of Vaxzevria were less reactogenic than the first dose.

It seems that those of us who patiently endured a five-month wait for their second dose of Covishield, may in fact, be better protected than those who, by whatever means they felt necessary, managed to secure their second dose in the previously recommended three-month dosing interval, before supplies ran out. As the old adage goes: good things come to those who wait springs to mind!

The release of the findings of a second study on July 28. 2021, by researchers from the University of Oxford, concluded that the risk of the rare blood clotting thrombocytopenia, venous thromboembolism and arterial thromboembolism after receiving first doses of AstraZeneca or Pfizer COVID-19 jabs is far lower than from the actual virus.

Rates of venous thromboembolism were eight times higher after a diagnosis of COVID-19 infection compared with the expected rate. Many developed countries limited AstraZeneca’s use to older adults because of concerns about an elevated risk of blood clots affecting the younger population. These findings should allay any fears about the vaccine’s safety.

Results from the Canadian Immunization Research Network with support from the Public Health Agency of Canada and the Canadian Institutes of Health Research, published as a pre-print on July 23, 2021, showed that one dose of Vaxzevria (Covishield) was 82% effective against Beta/Gamma and 87% and 90 % effective against the Delta (B.617.2, ‘Indian’) and Alpha (B.1.1.7, ‘Kent’) variants’ hospitalisation or death.

Research into the coronavirus is on-going and it important to ensure that officials keep abreast of new developments and plan accordingly. In countries such as Sri Lanka with limited resources, hard hit economically by Covid-19, where the majority of those under the age of 30 have yet to receive a first vaccine, the findings that Covishield’s antibody levels remain elevated from baseline for at least one year following a single dose, with increased immunity provided as a result of a longer dosing interval are potentially game-changing.

The Delta virus variant has changed the shape of the pandemic. At a time when the vaccination program is struggling to keep up with rapid transmission of the Delta variant, any Covishield vaccines kept aside for second doses, might be better utilised now as first doses to prevent hospitalizations and deaths in those higher risk as yet unvaccinated groups.


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Heat Index at Caution Level in  the  Northern, North-central, North-western and Eastern provinces and in Hambantota and Monaragala districts during the day time

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42 mins ago

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2026/05/5

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Warm Weather Advisory
Issued by the Natural Hazards Early Warning Centre
Issued at 3.30 p.m. on 04 May 2026, valid for 05 May 2026.

The Heat index, the temperature felt on the human body is likely to increase up to ‘Caution level’ at some places in  the  Northern, North-central, North-western and Eastern provinces and in Hambantota and Monaragala districts during the day time.

The Heat Index Forecast is calculated by using relative humidity and maximum temperature and this is the condition that is felt on your body. This is not the forecast of maximum temperature. It is generated by the Department of Meteorology for the next day period and prepared by using global numerical weather prediction model data.


Effect of the heat index on the human body is mentioned in the above table and it is prepared on the advice of the Ministry of Health and Indigenous Medical Services.

ACTION REQUIRED
Job sites: Stay hydrated and takes breaks in the shade as often as possible.
Indoors: Check up on the elderly and the sick.
Vehicles: Never leave children unattended.
Outdoors: Limit strenuous outdoor activities, find shade and stay hydrated.
Dress: Wear lightweight and white or light-colored clothing.

Note:
In addition, please refer to advisories issued by the Disaster Preparedness & Response Division, Ministry of Health in this regard as well. For further clarifications please contact 011-7446491.

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Maldivian President plants a sapling to mark 60 years of Sri Lanka–Maldives Diplomatic Relations

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6 hours ago

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2026/05/4

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President of the Maldives, Dr Mohamed Muizzu, who is on a State Visit to Sri Lanka at the invitation of President Anura Kumara Dissanayake, planted a sapling this afternoon (04) at Viharamahadevi Park in Colombo to commemorate 60 years of diplomatic relations between Sri Lanka and the Maldives.

Upon arrival at the Viharamahadevi Park in Colombo, President Dr Mohamed Muizzu was warmly received by President Anura Kumara Dissanayake. Children lined both sides of the pathway holding the national flags of the two countries and paid tribute to the visiting Maldivian President.

Among those present at the occasion were Deputy Speaker Rizvi Salih, Minister of Foreign Affairs, Foreign Employment and Tourism, Vijitha Herath and the Mayor of Colombo, Vraie Cally Balthazaar, along with several other dignitaries.

[President’s Media Division (PMD)]

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Sri Lanka and Maldives strengthen ties with productive bilateral talks

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6 hours ago

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2026/05/4

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Following the bilateral meeting between President Anura Kumara Dissanayake and President Dr. Mohamed Muizzu of the Maldives, who is currently on a State visit to Sri Lanka, official-level bilateral discussions between the delegations of the two countries were held this morning (04) at the Presidential Secretariat.

The discussions commenced after the formal welcome ceremony accorded to President Dr. Mohamed Muizzu earlier this morning within the Presidential Secretariat premises.

Extending a warm welcome to the Maldivian President, President Anura Kumara Dissanayake expressed his appreciation for accepting the invitation to visit Sri Lanka.

President Dissanayake noted that President Muizzu’s visit, taking place as the two nations mark 61 years of diplomatic relations, reflects the strong partnership, mutual trust and longstanding friendship between Sri Lanka and the Maldives. The President further expressed confidence that the visit would mark a new phase in bilateral relations.

The two leaders engaged in extensive discussions on ways to further expand and diversify multifaceted cooperation, including economic, cultural and social ties, in a manner that delivers mutual benefits to the people of both countries.

Key areas of focus included tourism promotion, educational cooperation, youth and sports development, challenges faced by both nations in the fisheries sector within the Indian Ocean region, education and vocational training, as well as defence training and broader security cooperation.

Representing the Government of Sri Lanka were Minister of Foreign Affairs, Foreign Employment and Tourism, Vijitha Herath, Minister of Labour and Deputy Minister of Finance and Planning, Anil Jayantha Fernando, Minister of Science and Technology, Krishantha Abeysena; Deputy Speaker Rizvie Salih, Secretary to the President, Dr. Nandika Sanath Kumanayake, Secretary to the Ministry of Defence, Air Vice Marshal Sampath Thuyacontha (Retired), Additional Secretary to the Ministry of Foreign Affairs (covering Europe, North America, East Asia and Oceania, Southeast Asia and Central Asia, South Asia, the Middle East and Legal Affairs) M. R. K. Lenagala, Sri Lanka’s High Commissioner to the Maldives, Mohamed Rizvi Hassan and Director (South Asia and SAARC) of the Ministry of Foreign Affairs, Foreign Employment and Tourism, Mahesha Jayawardena.

The Maldivian delegation included Minister of Foreign Affairs Iruthisham Adam, Minister of Economic Development and Trade, Mohamed Saeed, Minister of Fisheries, Agriculture and Marine Resources, Ahmed Shiyam, Minister of Homeland Security and Technology, Ali Ihusaan, Chief of Staff to the President, Abdulla Fayaz, Principal Secretary to the President on Foreign Relations, Mohamed Naseer; Chief Government Spokesperson, Mohamed Hussain Shareef, High Commissioner of the Maldives to Sri Lanka,Masood Imad; Minister of State for Foreign Affairs and Chief of Protocol , Mohamed Shahudy, Deputy Minister at the President’s Office, Mr Mohamed Hassaan and Minister Counsellor at the Maldives High Commission in Sri Lanka, Mr. Ismail Mamdhooh.

[President’s Media Division (PMD)]

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