What you need to know about Covid-19 vaccines

By the end of last year, Uganda had received several donations of Covid-19 vaccines through the covax facility and those that were brought directly from the US, India and Russia. These vaccines include the most common AstraZeneca, Moderna, Sinovac, Pfizer, Johnson & Johnson, and Sinopharm.

According to Emmanuel Ainebyoona, the spokesperson of the Ministry of Health, six vaccines are approved for use in Uganda. Most of these vaccines are also largely used in the United Kingdom, South Africa, China and other countries and its these countries that have also donated some to Uganda.

AstraZeneca

The commonly administered Oxford-AstraZeneca (AZD1222) was developed in the United Kingdom. There are, however, two versions of this vaccine that are being produced by AstraZeneca-SKBio (Republic of South Korea) and the Serum Institute of India. Both versions have been approved for emergency use by the World Health Organisation (WHO). This vaccine is taken in two doses at an interval of between eight to 12 weeks. 

According to WHO, this vaccine may not be suitable for persons with a history of severe allergic reactions.

Sinopharm

This was developed in China and is taken in two doses and an interval of three to four weeks. “If the second dose is administered less than three weeks after the first, the dose does not need to be repeated. If the administration of the second dose is delayed beyond week four, the dose should be administered at the earliest possible opportunity,” says WHO.

Pfizer 

The Pfizer-BioNTech (BNT162b2) vaccine was developed by the US and German pharmaceutical companies, and is taken in two doses. The WHO recommends Pfizer as being safe and effective for people with health conditions such as hypertension, diabetes, asthma, pulmonary, liver or kidney disease, as well as chronic infections. 

It is recommended that the vaccine be administered at an interval of between 21 and 28 days but in case of an infection before the second dose, it can be delayed until the person has properly healed, preferably after 12 weeks. 

Morderna 

Moderna (mRNA-1273) was developed in the US and is taken in two doses. According to WHO, this vaccine is ideal for pregnant women and can be taken by persons with health complications such as chronic lung disease, significant cardiac disease, severe obesity, diabetes, liver disease, and human immunodeficiency virus (HIV).

This vaccine should be taken at an interval of 28 days but can be stretched to 42 days to pave way for higher first dose vaccinations or make time for more vaccine deliveries.

Johnson & Johnson

Johnson & Johnson (Janssen Ad26.COV2.S) was developed by Janssen Pharmaceuticals in Belgium. It is taken in a single dose and is safe and effective for people with known medical conditions that are associated with increased risk of severe Covid-19 disease according to WHO. 

These medical conditions include allergic reactions, hypertension, chronic lung disease, significant cardiac disease, obesity, and diabetes. It can also be given to people who have contracted Covid-19 in the past six months.

Sinovac

The Sinovac-CoronaVac vaccine is administered as two doses intramuscularly with an interval of two to four weeks between the first and second dose. 

The vaccination is recommended for persons with comorbidities such as obesity, cardiovascular disease and respiratory disease. It is also safe for people who have had Covid-19 in the past. The vaccine is not recommended for persons younger than 18 years of age.

WHO recommends an interval of two to four weeks between the first and second dose. Its use is recommended for people above 18 years but should not be taken by people with a history of allergic reactions.

WHO recommends that persons who present with fever and a temperature of 38.5 degrees Celsius should not take the vaccine until their temperature and fever have subsided. 

When to get a booster

According to Dr Moses Ocan, a lecturer from the department of Pharmacology and Therapeutics, Makerere University and President, Uganda Pharmacological Society, the immunity from the vaccines is short lived and therefore, people should get the booster doses at the earliest opportune time no matter what type of vaccine is offered. 

“The immune response is triggered four weeks after the vaccine is administered and this lasts three months. It does not matter about the initial vaccine you got when it comes to getting a booster vaccine because the immune response stimulation is the same for all the approved vaccines,” he says.

The challenge

The challenge according to Dr Ocan is that since the country has not been able to purchase its own vaccines, many of the doses that have been donated are nearing their expiration date.

“The challenge is about the vaccine shelf-life. There is vaccine uptake hesitancy across the country and, therefore, many vaccines are likely to expire unless the turn up increases in several parts of the country,” he says.

What we knew previously about vaccines is that it would protect the individual and the person next to them but this is not the case with the Covid-19 virus. 

This is one of the reasons many people are hesitant about taking the vaccines, but Dr Ocan warns: “The protection of the vaccines is from severe disease and everyone needs to be vaccinated in order to have healthy people who do not have the disease. Different variants keep coming up and fortunately, the vaccines that are available effectively suppress all the variants so far.”

The vaccination also would save one from the exorbitant costs involved in the treatment of a severe Covid-19 that requires one to be admitted to the ICU.

What the ministry should do

Slow vaccine uptake is a global challenge as not many people willingly go to get vaccinated the same way they would if they were sick. The government should educate and not coerce people to get vaccinated. 

“Since we are giving the vaccines to healthy people, there is usually hesitancy. It is, therefore, the mandate of the government to convince and educate people that it does not have the capacity to treat very many critical cases that can arise when there is no vaccination. People should know the advantage of getting vaccinated,” Dr Ocan says.

More caution 

There is currently no substantive data available related to the impact of Covid-19 vaccines on the transmission of the Coronavirus that causes Covid-19 disease.

In the meantime, WHO reminds people to stay safe and continue practising public health and social measures that should be used as a comprehensive approach to prevent infection and transmission of the virus. These measures include wearing a mask, physical distancing, and hand washing, respiratory and cough hygiene, avoiding crowds and ensuring adequate ventilation according to local national advice.

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